Crawley Amateur Radio Club Newsletter

Mechanical Components

2012-01-26T21:57:00.001Z

A useful site for small mechanical components

http://www.modelfixings.co.uk/index2.htm

UKAC 432MHz 10th Jan 2012

2012-01-26T21:32:00.008Z

I (G4VFL/P) operated from Ditchling Beacon (IO90wv) here are the results. I went to this site for a number of reasons, the home QTH is not good for UHF and it activates a SOTA. If you look at the claimed scores for last year there are very few stations in IO90 and JO00. I used IO90 because it is an easy access site with a car park on top and is seen as a rare square. Below is a table of the grids used from the claimed scores.

Callsign	Count
IO75 Count	2
IO78 Count	1
IO80 Count	1
IO81 Count	4
IO82 Count	5
IO83 Count	25
IO85 Count	2
IO86 Count	1
IO90 Count	3
IO91 Count	8
IO92 Count	14
IO93 Count	6
IO94 Count	4
JO01 Count	11
JO02 Count	4
Grand Count	91

I have a very simple station that minimises the number of connectors, does not involve spanners (I use wing nuts) and uses paper logging. This means it can be assembled in the dark and reduces the risk of exposure to faults. The station is portable by my self in a single carry for a few 100 metres and is setup in about 15 – 20 min.

In short the station consists of:

IC-7000 (35W on 432MHz)
19 ele Tonna
SLAB 7AH (2 off)
Coax (7m)
Mast 4.5m (25mm and 20mm steel conduit)
Trig Point fixing jig
Paper and Pencil log
Headlamp
Chair

The SLABs require about 3 – 4 AH to recharge after the contest so I rate them at 50% of the manufactures rating for this use. I cannot do the contest on a single SLAB it will be exhausted after about 1.5 hours.

Here is a picture of the station, not the world’s best picture in the dark !.

Here is another in daylight for the 50MHz Xmas contest from Cliffe Hill (JO00AV)

Results are shown below, I didn’t put them in for the club because it was not a club arranged station. (I am quite happy to tag them with the club if the club is happy) Based on the claimed scores I am 24/91 overall. I only call CQ about 30% of the contest to conserve battery capacity.

Date	Time	Call	Sent RS	Sent S/N	Rx RS	Rx S/N	Loc	Dist	Mult	Heading
10/01/2012	20:00	G0XDI	59	1	59	3	IO91RQ	93	IO91	342
10/01/2012	20:02	G4CLA	57	2	57	6	IO92JL	192	IO92	337
10/01/2012	20:04	G1VVE	57	3	55	8	IO91SG	48		331
10/01/2012	20:08	G0ODQ	59	4	59	8	IO91MR	110		328
10/01/2012	20:11	G0RRC	57	5	59	3	JO02MB	153	JO02	31
10/01/2012	20:13	G0PKT	59	6	59	8	JO01MT	131	JO01	38
10/01/2012	20:15	M0MCV	57	7	57	2	JO01AL	66		10
10/01/2012	20:16	G5MW/P	59	8	59	6	JO01GI	87		42
10/01/2012	20:19	G8MCA	55	9	53	14	JO01BK	63		16
10/01/2012	20:22	G3XDY	59	10	59	8	JO02OB	160		35
10/01/2012	20:30	M0GHZ	53	11	52	17	IO81VK	158	IO81	293
10/01/2012	20:46	M1MHZ	59	12	59	16	IO92WV	223		0
10/01/2012	20:51	G4GFI	59	13	59	6	IO91VH	47		353
10/01/2012	20:54	G4JED	59	14	59	9	JO01CF	44		32
10/01/2012	20:55	G4LDR	53	15	53	12	IO91EC	108		283
10/01/2012	20:58	G8XRL	53	16	52	5	JO01QX	160		40
10/01/2012	20:59	G0AJJ	57	17	55	10	JO02QT	237		25
10/01/2012	21:01	G6RVS	59	18	59	2	JO01FG	59		44
10/01/2012	21:05	GW8ASD	52	19	53	27	IO83LB	313	IO83	321
10/01/2012	21:06	G4NBR	59	20	59	12	IO92VU	218		359
10/01/2012	21:09	M0BPQ	57	21	55	11	IO91WP	84		0
10/01/2012	21:10	G8LZE	57	22	59	10	IO91SO	83		344
10/01/2012	21:12	G4FAA	57	23	43	10	JO01BK	63		16
10/01/2012	21:14	G6HIE	54	24	57	4	IO90ST	26	IO90	249
10/01/2012	21:16	G4SJH	58	25	58	14	IO91PI	66		322
10/01/2012	21:18	G1HIT	54	26	54	32	IO93JD	261	IO93	344
10/01/2012	21:19	M0WAF	59	27	59	22	IO92VN	186		358
10/01/2012	21:21	G3BNE	58	28	57	14	JO01BJ	59		17
10/01/2012	21:23	G3XBF	58	29	53	9	JO01BO	81		12
10/01/2012	21:27	G4YPC	51	30	51	2	IO91RH	55		328
10/01/2012	21:41	G3PYE/P	59	31	58	56	JO02CE	146		9
10/01/2012	21:47	G3TCU	59	32	59	2	IO91QE	48		313
10/01/2012	21:52	M0PXM	53	33	59	2	IO91KI	87		307
10/01/2012	21:58	G4NBS	52	34	52	43	JO02AF	149		4
10/01/2012	22:03	G1DFL	52	35	51	1	IO91NL	84		321
10/01/2012	22:15	G0RAF	51	36	51	16	IO93RF	262		354
10/01/2012	22:16	G4ODA	56	37	57	34	IO92WS	209		0
10/01/2012	22:20	G6UBM	52	38	51	6	JO01CE	40		36
10/01/2012	22:25	G4KIY	54	39	57	9	IO92WN	186		0
10/01/2012	22:29	G4FZN/P	53	40	54	54	IO94JF	378	IO94	349

My plan for the year s to use this site for the 432MHz contests assuming I can escape from work early enough.

Titanic Centenary – Station GR100MGY

2012-01-26T21:27:00.002Z

Wey Valey Amateur Radio Group

(www.wayvalleyarg.org.uk)

Press Release No. 1

23 January 2012

The sinking of White Star Line’s RMS Titanic on 15^th April 1912 sent shock-waves around the world and has touched our hearts ever since. Those who perished in this disaster will be remembered on its 100^th anniversary during many commemorative events.

Within amateur radio we recognise that this event marked the first time that Morse code saved so many lives at sea. Jack Phillips (1887-1912) was the liner’s Chief Marconi Wireless Operator. He perished only after sending distress signals in Morse right until the ship foundered, thereby saving hundreds of lives. Jack was from Godalming, Surrey, where his heroism is constantly recalled. A group of local radio amateurs commemorated his heroism on the 90^th anniversary of the sinking by setting up a radio station in Godalming with the call-sign GB90MGY. The letters ‘MGY’ were used by RMS Titanic for all its radio transmissions. Five years later, the Wey Valley Amateur Radio Group (WVARG), activated a similar commemorative station in Godalming, this time using GB95MGY.

For the 2012 centenary a much larger project to honour Jack’s memory will be mounted in Godalming by the Wey Valley club. From Tuesday 10^th April (when Titanic sailed from Southampton), until the day of the sinking, Sunday 15^th April, two transmitters will be manned continuously, with the special call-sign GR100MGY (Godalming Remembers the Centenary of the Titanic Disaster). There will be a short pause in transmissions at 05.47 GMT on the Sunday, the time when distress messages ceased minutes before the liner sank. The transmitters will make contacts around the world, mostly in Morse code, targeting 15,000 two-way exchanges. Each contact may be confirmed with a specially printed card depicting Titanic and Jack Phillips.

We offer our grateful thanks to Charterhouse for providing operating facilities at their excellent Godalming location, to Ofcom for allocating the special call-sign and to Waverley Borough Council and Godalming Town Council for their support and embodying this event in their commemorative programme.

During Saturday 14^th and Sunday 15^th April, from 12.00 noon until 4.00pm, the general public will be welcome to visit the station to observe the transmissions and to participate in this memorable commemorative event.

Further information: Michael Shortland, G0EFO, michaelgs1@talktalk.net

##############

For Amateur Radio Publications

Some fifteen operators will man two 400 watt transmitters on the eight HF bands from 3.5 to 28 MHz , using directional antennas. Only CW will be used except on the open days, 14-15^th April, when SSB will help the public to understand the operation. Activity on VHF is also planned. QSL information can be found at: http://www.QRZ.com.

GR100MGY will be located at 0° 37’ 18” West, 51° 11’ 49” North, Locator IO91qe: Charterhouse, Hurtmore Road, Godalming, Surrey, GU7 2DX.

CARC Programme 2012 (Jan) - Issue 2

2012-01-09T17:09:00.003Z

Issue:	January 2012
Meetings:	Every Wednesday Evening commencing 8.00 pm
	Every Sunday Morning from 10.30 a.m.
Main Meetings:	4^th Wednesday in the month starting at 7.45 for 8.00pm (unless otherwise advised.)

MONTH	DATE	TOPIC	BY
January	Wed 18^th Wed 25^th	The GB3VHF Beacon Story. Chris G3FDZ recounts the origins of the beacon from its early beginnings to its present update state as a precision frequency reference and propagation indicator. Annual General Meeting. One of the most important meetings of the year and your opportunity to have your say and improve how your club is run. An important date for your diary!	Chris Whitmarsh G3FDZ
February	Wed 29^th	The T32C Experience. The 2011 Five Star Dxer’s Association DXpedition to Christmas Island was a ground breaker, both for the massive total of QSO’s, and also band totals. Team member Mike Chamberlain G3WPH has agreed to come along and give a presentation on this major DX event.	Mike Chamberlain G3WPH
March	Wed 28^th	Surplus Equipment Sale
April	Wed 25^th	Blue Joker. This was a radar system suspended below two balloons. The RAF tested Blue Joker at Drum near Llanfairfechan, in the early/mid 1960s. Derek was involved with the tests.	Derek G3GRO
May		Dayton 2012 A rundown of the greatest show on earth, hopefully with some video footage.	John G3VLH, Stewart G3YSX, Mike G3LHZ
June	Wed 27^th	Fox Hunt
July	Wed 18^th	HARC/CARC Challenge. A long way ahead, but put it in your diary!!

DK7FC 136KHz Station at University of Heidelberg

2012-01-06T22:07:00.005Z

Those of you that helped Derek measure out and coil the Litz wire at the club a few months back may be interested to here of the good use to which it was put. Here is a short email exchange
between Derek G3GRO, and Stefan DK7FC that is reproduced with permission.

Dear Derek,

Just want to give you a feedback:

A few weeks ago we ordered some 100m of ex Decca RF litz wire. It took me only a few weeks to build a new loading coil for my 137 kHz system. The wire is wound on a glass coil body of 300mm diameter, about 155 turns plus a small variometer part which is driven by a remote controlled drive engine, to accurately resonate on any frequency in the band.

I achieved a Q of about 1000 which lowers the coil losses by 6 dB, compared to the older one. This makes my system even more effective. My antenna is a 70m long wire in 30m height, with
extremely low earth losses.

Last friday it was possible to for Joe/VO1NA and me to have a first transatlantic detection of a ham generated CW signal in New Foundland, just like in Marconi's tests You can find a short

Report and a wav file to listen for my CW on his page at
http://www.ucs.mun.ca/~jcraig/lfex.html

There are many stations in Canada and the US who can receive my signals almost daily.

Thanks again for the possibility to get that most useful RF litz wire which improves my system significantly!!!

Best 73, Stefan/DK7FC

Dear Stefan,

Many congratulations on making your first transatlantic two-way QSO on the 137kHz band with Joe, VO1NA using your new high Q loading coil and variometer to tune your antenna - you must be delighted with your antenna performance. Thanks for the feedback I would be interested to know what earth system do you use at your QTH.?

The best two-way DX I ever achieved on 137 kHz was to OH1TN in Finland using hand-keyed CW. My LF antenna was then a 45m long wire with a similar loading coil to yours but the antenna was at only 12m AGL and somewhat screened by conifer trees almost as high and.fairly
close by! I did however manage to make a cross-band QSO down to a UA3 in the Russian Black Sea region at 2200km distance but that was when using the old Decca 100m mast as an antenna by special permission !! -

Unfortunately I am not currently QRV on the 137kHz band at present.

Thanks again for the feedback

73 and vy best Wishes, Derek/G3GRO

Dear Derek,

Well it was not a 2 way QSO but "just" a detection by VO1NA. There is not much going on in QSO activity you know but a lot of OMs are concentrating on beacon transmissions these days, which is interesting too. However I plan to do acty in CW, like today. But i need to improve
my RX since there have been many OMs answering my call but i didn't hear them I started with LF operation in autumn 2003 until spring 2004 and then had a break until autumn 2009 where I came back with some /p experiments using a 100m kite vertical. In 2003 i also worked OH1TN/OH5UFO and many other stations.

Well, about my earth system. The antenna is mounted here at my work which is the institute of environmental physics at the University of Heidelberg. This is a 35m high building. Since it is a German official and relatively new building they put much money in all the equipment and realized an EXCELLENT earth system. So i simply had to connect the cold end of my coil to the lightning protection system. Now, my earth losses are 1.2 Ohm! When using the new coil i am getting an overall loss resistance of 5 Ohm (recently measured 4.8 Ohm) including the PA and LPF losses, i.e. i am getting 1 A antenna current at 5 W RF I'm sure there would be no problem to appear in DFCW-60 on the G4WGT grabber when using a 9 V block battery and running 1W RF... This makes it clear why the RF litz caused a 3 dB improvement of that system. Assuming a Q of 1000 and j2500 Ohm for the coil i am at 2.5 Ohm now. Before, it was 8.7 Ohm. If someone has 50 Ohm earth losses, the improvement would have been marginal...

Best 73, Stefan/DK7FC

Stefan then sent us a photograph of his system on the roof of the University building

Stewart/G3YSX

Getting G6CBX for Clement.

2012-01-06T21:54:00.002Z

Here is some information on how we did it just in case you are asked or see a opportunity for someone else to do the same in the future.

History

I (Andrew Holland) took the RAE in 1969 aged 16 and passed. I was tutored by Neville Ramsden G3RHE because a friend at school said “Neville would only tutor him (Malcolm Monro G8DLL) if he found someone else to do the RAE”. So off we went to Neville’s house once a week for about 6 weeks with our copies of the RAE book which we were expected to have read. The main gap in my knowledge was in the maths to using “powers of 10” Neville assumed we did this at school and because I was B stream I hadn’t, Malcolm who was A stream had. The result a 10pf * 10uH tuned circuit looks like this.

F = 1 / 2 * 3.14 * SQRT (0.00000000001 * 0.00001)

miss count the number of zeros and you are in trouble !

Malcolm got a license straight away and I thought I would do the Morse. So having no structure and a lot of patience from John Colbook (G3BJD) once a week I got nowhere and went off bell ringing, a loss to radio ? I continued with the electronic building at work for the Post Office (Telephones) and at home.

The next contact (1976) with Amateur Radio was in Kenya where I went to work for the Flying Doctor Service as a Volunteer (VSO) where I took over from Mike Franklin (G3VYI & 5Z4NX) looking after about 80 HF ground stations in Kenya and Tanzania. PYE SSB125T and SSB130 kit. Mike could whistle the Morse so no key was required to deal with another user who tried to borrow our frequency. I just left the situation alone and the Flying Doctor Radio operator for that frequency seemed to like knowing about what was happening in the Kenya Prison service.

So a few years later (1981) I was now working at the Post Office Central Training School at Stone, Staffs and I meet up with Dave Powis (G4HUP) who was after operators for the club contest station. So no kit required, which was good news with mortgage rates at 15%, I finally get my license (G6CBX). The club used Dave’s Call for VHF contests which were good fun.

Back to the Morse, this was with Dave in a very different manner, it was half an hour every lunch time at 16WPM then off to Cullercoats Radio (http://www.coastalradio.org.uk/ukstations/cullercoats/cullercoats.html) to do the Morse test followed by an upgrade to G4VFL. So after about 2 years G6CBX which had little use in its own name went QRT.

G4VFL has had its ups and downs but less of that.

The re-issue of G6CBX

Clement had taken an interest in things technical so I suggested that he could get a license thinking it would be a process similar to when I got mine. Not so, so Clement has worked his way through the Foundation and Intermediate followed by the Advanced. I think the process has been good for Clement. I do have some issues with it as the only solution to getting a license, but this is not the place to air those views.

So as Clement approached the Advanced exam I though about the call sign, he really hated the 2E0 so it was an M0 or could he get a G call sign ?

The International agreement says call signs are not normally reissued however there are exceptional circumstances.

There are two documents on the Ofcom website:
http://www.ofcom.org.uk/static/archive/ra/publication/ra_info/ra190/ra190.htm (dated 2002)

Can a call sign be passed on to another amateur?

We are aware of some instances of unwelcome approaches to the families of deceased amateurs, seeking their call sign. Whilst it is usually the case that such approaches are due to an over enthusiastic reaction to obtain an attractive call sign the only way to avoid problems of this nature is to restrict the type of requests for transfers that we would consider. Furthermore, transferring call signs puts quite an administrative burden on the RLC and the Agency at the expense of other licensees.

Requests of this kind will only be considered on a discretionary basis e.g. where the request comes from a member of the "immediate family" of the deceased. In addition, the Agency will consider requests made in a will. We may also consider cases where the "immediate" member of a family becomes a Class B licensee and wishes to adopt the original Class B call sign once held by another member of the family who now holds a Class A Licence.

Also this document that doesn’t appear to be linked but I located on search.
http://licensing.ofcom.org.uk/binaries/spectrum/amateur-radio/guidance-for-licensees/amateur-radio-call-signs/transfercallsigns.pdf

General call sign allocation policy

1.1 This document describes the circumstances under which Ofcom will consider transferring a call sign from one radio amateur to another.

1.2 According to ITU Regulations “All stations open to international public correspondence, all amateur stations, and other stations which are capable of causing harmful interference beyond the boundaries of the territory or geographical area in which they are located, shall have call signs from the international series allocated to its administration as given in the Table of Allocation of International Call Sign Series.”

1.3 Within the hierarchical structure of call sign allocations granted by the ITU, the UK allocates blocks of these call signs to the various radio services (including the amateur radio service) in accordance with formats specified in the ITU Radio regulations.

1.4 Once issued, the amateur radio call sign is permanently associated with the individual concerned and is not re-issued. An individual’s call sign will only be changed under exceptional circumstances. Similarly, the transfer of a call sign from one radio amateur to another is not normally permitted except under exceptional circumstances.

1.5 Should a radio amateur allow their licence to lapse, their call sign will be re-instated if they subsequently choose to renew their licence.

1.6 Call signs are a finite resource and remain the property of Ofcom.

Section 2
Transfer of amateur radio call signs

Consent to transfer the call sign

2.1 Ofcom will transfer a call sign from one radio amateur to another radio amateur providing that the call sign holder consents to the transfer.

2.2 Ofcom will require a letter of instruction from the call sign holder as evidence of consent.

2.3 Ofcom will also transfer a call sign from a deceased radio amateur to another radio amateur.

2.4 Ofcom will require a letter of instruction from the call sign holder’s executor (or administrator) as evidence of consent.

Other requirements

2.5 Ofcom will only transfer the call sign if the recipient is entitled to hold a licence of an equal class or of a higher class to the donor.

So with this we sent a manual application form for a license to Ofcom.

I annotated the policy document as follows:

1.4 Exceptional circumstances being a son of an Amateur that has a class B in the past and upgraded to a class A and the son was still interested in Amateur Radio.

1.5 The call sign had lapsed because of the issue of a class A call sign G4VLF and would not be required to be reissued to me at any time, because I have call sign G4VFL.

1.6 This reissue would save the issue of a new call sign thus conserving the stock of call signs.

2.1 Consent provided

2.2 Letter provided, I included in the letter the details of the old G6CBX call sign and its station address with a copy of the log book to illustrate it has not been heavily used in the 2 years it had been open for operations.

Allocation of call sign G6CBX to a new holder

Dear Sir

Would it be possible to allocate my old Class B call sign (G6CBX) to my son ? He has just passed his Full License exam. This call was only used for a short period before I obtained a Class A call G4VFL and the G6CBX license handed in to obtain the upgrade. The station address at the time was 67 Meadow Way, Stone, Staffordshire, ST15 0JW. A full log of the contacts with the call is attached, as you see it was not extensively used and it is approaching 30 years since it was used so there should be no overlap confusion in operations with the call sign.

My son currently holds the 2E0CEZ call sign, it would be nice for him to hold a “G” call sign.

I have separated the payments for the Call sign transfer and the license issue.

Yours sincerely

Andrew J Holland

G4VFL

We submitted a manual application for a license with two payments, one for the license transfer (£15) and one for the manual issue of a license (£20). A week or so later the license was issued with no reference back to us.

I hope this note may be of help and can add to the knowledge base.

Hacking 1903 style

2012-01-02T10:24:00.003Z

A pointer to this new scientist article appeared on the QRP-L list.

http://www.newscientist.com/article/mg21228440.700-dotdashdiss-the-gentleman-hackers-1903-lulz.html?full=true

It seems that there is nothing new under the sun, this could so easily have been an article on one of today's technologies.

Stewart/G3YSX

The Future of Digital Amateur Radio

2012-01-01T21:33:00.002Z

Yaesu have just published an interesting paper on digital modulation in amateur radio

http://www.yaesu.com/downloadFile.cfm?FileID=7146&FileCatID=151&FileName=DigitalCommunicationsGuide%5FE%5B1%5D.pdf&FileContentType=application%2Fpdf

It looks like they are getting ready to make some serious announcements this year.

What will be very interesting is what is going to happen with respect to spectrum availability since between analogue and D-Star there is, as we know well, nothing much available. The first mover advantage is with Icom, so Yaesu system will need an overwhelming advantage to get a foothold in the market.The key deciding factors will likely be whether the new system is truly open, both in terms of system design and codec.

Stewart/G3YSX

Raspberry Pie

2012-01-01T21:27:00.002Z

Fancy some raspberry pie?

No - not to eat - look here

http://www.raspberrypi.org/

or here for more technical details

http://elinux.org/RaspberryPiBoard

Yes, it's a £15 pound computer capable of running Linux and I can see it taking the experimental and amateur radio world by storm.

Stewart/G3YSX

Elizabeth (Liz) Laszkiewicz

2012-01-01T14:30:00.002Z

It is with deep sadness that I have to inform the club that Liz, wife of Lech (G3KAU), passed away peacefully at home last Thursday with many of her family around her. Many of you will remember meeting Liz at numerous club social events over the years. Liz had been unwell for quite some time and had been in receipt of chemo-therapy for several months.

Our thoughts are with Lech and his family at this very difficult time.

Stewart/G3YSX

Club Activity Over Christmas

2011-12-28T16:16:00.001Z

There was a reasonably good turn-out for the Christmas-Eve Club net on the GB3MH repeater timed to start at 8-0pm on Saturday December 24th . The call-signs checking-in included Stewart,G3YSX Hon, Chairman CARC; Peter, G4FYY; Graham 2E0XDZ; Richard G4ANN/M; Nick, M5DND/P Bitan, M0WAO; Brian, 2E0MZB; David M0IDD and Derek, G3GRO. It was pleasing to see that recently issued call-signs were well represented and also pleasing to be able to exchange Season's greetings with Nick M5DND/P who is a member of the Dorking Club now living and working in the Shropshire area but currently visiting family locally for Christmas. - Crawley committee members came in regular contact with Nick in the past as fellow participants in the Southern Counties inter-club liaison organisation, SCARF. Nick was very complimentary regarding the GB3MH/GB7MH project not only for its excellent coverage but also for the high level of technical expertise and amount of organisational effort involved.

DON'T FORGET : CARC Clubhouse will be open as usual, 20-00 Hrs Wednesday 28th Dec.and New Year's Day Club Net on GB3MH at 11-00 am.

A Morse Decoder Button

2011-12-23T18:37:00.002Z

Whilst flicking through the pages of CQ Magazine in the ITU-T library earlier this month, I came across an advertisement for a small button to be used as a crib for Morse code. The send side of the button was pretty obvious, but I rather liked the receive side shown above.

I have no idea where you get these or what they cost, but I thought that the representation style was quite good.

Stewart/G3YSX

Ronald Vaughan, VK6RV, SK

2011-12-23T14:51:00.002Z

It is with regret that I need to inform the club that Ronald Vaughan, VK6RV (RSARS 3595), the founding Secretary of the Crawley Club, passed away today at 3:40pm (0740Z) this Friday, 23rd December 2011 at the Como House Nursing Home Australia.

We received this sad news from his close friend Alan Gibbs, VK6PG, a CARC life member, earlier today. Alan reports that he took Eileen to see Ron at the Nursing Home yesterday but he was sedated and in a deep sleep from which we could not wake him.

Alan says that in due course he will notify us of further arrangements when available, and will relay messages to Eileen as required.

Our thoughts are with Ron's wife Eileen Vaughan who is currently in hospital recovering from a hip joint replacement.

Stewart/G3YSX

Annual General Meeting Agenda : Wednesday 25th January 2012

2011-12-23T09:45:00.002Z

Notice is hereby given that the Annual General Meeting of the Crawley Amateur Radio Club will be held on Wednesday 25th January 2012 at 20.00. The meeting will be held in the Clubhouse, Hut 18, Tilgate Forest Recreational Centre, Crawley.

The Agenda for the meeting is as follows:

1. Apologies for Absence

2. To approve the minutes of the Annual General Meeting held on the 26th January 2011.

3. To discuss any Matters Arising.

4. To receive the Chairman’s Report for the year ending 31st December 2011.

5. To receive the Audited Balance Sheet and Accounts for the year ending 31st December 2011, together with the Hon. Treasurer’s Report and to pass a resolution adopting the Accounts.
A copy of the Audited Balance Sheet and Accounts for the year ending 31st December 2011 will be available at the meeting

6. To pass a resolution fixing the subscriptions for the year ending 31st December 2012.

7. To elect for the year ending the 31st December 2012:

1. Chairman
2. Vice Chairman
3. Hon. Secretary
4. Hon. Treasurer
5. Newsletter Editor
6. Training Secretary
7. Up to five Committee Members

8. Any Other Business

BY ORDER of the Committee
Alexander Sheppard (M1YAP) Hon. Secretary

Note : All paid-up members for 2011 are entitled to attend and to vote at the meeting and to nominate Officers and Committee Members.

Minutes of the previous AGM have been emailed to members. Any member requiring a hard copy can receive one, on request at the club house during normal meeting hours. In order to ensure a timely start to the AGM please bring a printed copy the agenda and the minutes to the meeting.

Club Opening over Christmas Period

2011-12-18T17:33:00.002Z

This is a reminder of the club plans over the Christmas holidays.

At the committee meeting last night, we discussed the Christmas 2011 opening times which are a bit problematic this year due to the days of the week on which Christmas Day and New Year's day fall.

Here is the plan:

Sat 24th Dec Christmas Eve there will be a club net at 8pm on GB3MH

Sun 25th Dec CLOSED

Wed 28th Dec OPEN as normal

Sun 1st Jan New Years Day CLOSED but here will be club net at 11am on GB3MH

Normal service from 4th January 2012

If any key holder wishes to open on Christmas Day or New Years Day they are of course welcome to do so, and should let rest of the club know.

Stewart/G3YSX

November Meeting HARC/CARC Challenge

2011-12-18T17:15:00.005Z

This year’s HARC/CARC Challenge, held on 30th November and hosted by the Crawley Club, got back, as Adrian G4LRP said, to basics. Of the Horsham team Alister G3ZBU was the tech support who made the idea come to life and supplied the kits, and David G4FQR was the HARC constructor, ably assisted by Paul G4TMC. Robin G3OGP was the CW op. The Crawley Club fielded Derek G3GRO, Stewart G3YSX, Richard G4ANN and Biton Walstra (2E0WAO). The two judges were Adrian G4LRP from HARC, and John G3VLH from CARC.

Set by Horsham this year the task was for each team to build a single valve transmitter, a simple receiver, fabricate a Morse key fabricate from a broken CD (don’t ask!), connect a short wire antenna and send half a page of Morse. All required components, including four 1.5V pen cells and two 9.0 volt PP3 batteries, plus the circuit diagram, were supplied in bags by Horsham. Both receiver and transmitter would be built on small screw type tag strips so no soldering was required. The winning team would complete the building process and send the prepared CW with the fewest errors. Alister would act as guide/consultant for both teams. Adrian suggested that the transmitter would take 10 minutes, the receiver ten minutes and the CW transmission another ten minutes. Thirty minutes total? Ho, Hum!

The transmitter, a single valve crystal oscillator resonant on 80m used a cathode-keyed 6BA6 and comprised about a dozen components. An audio oscillator using a 555 timer chip on a piece of pre-assembled Vero board supplied the modulation. The receiver was a simple crystal set, the output of which was connected to the input of a small active Sony speaker. Each component was screw-connected to the tagstrip using a screwdriver, the only tool required for the building process.

As Adrian whispered to me half way through the construction phase, there was an element of the tortoise and the hare in the way each team approached their tasks. As the pen cell batteries had limited capacity but had to power the valve filaments, if you spent a lot of time fault finding with the power connected you could literally run out of steam before completing the CW transmission. Whereas, if you were slower but more methodical with the construction process, you could have power in hand to complete the transmission.

First to complete their construction was the Horsham team, then Robin G3OGP sent the half page of code which was received by Alister, and took around 15 minutes.

Crawley was struggling by this time, but after some dogged fault-finding detective work they also had their system up and running. Time for some CW from the home team! Derek G3GRO had been elected as CW op and Ted and Dick both did the receiving bit. The fact that HARC had by this time finished their transmitting session in fact worked out well as there was no QRM.

Again the CW transmit session took about fifteen minutes – and then it was time for the judges to come forward and have their say. The prepared CW was from about half a page of plain language text divided up into 5-letter groups. And this was the deciding factor. The Horsham text checked out by Adrian had been very accurately sent and copied. However, when John checked the Crawley club effort two vital lines were missing from the text.

So the Horsham Club regained the Interclub Cup, which was presented by CARC Chairman Stewart to HARC Chairman Adrian. It had been a truly well thought out project and provided an entertaining evening for all present, whether actively taking part or watching from the sidelines. Congratulations and well done, Horsham. See you next year!

John G3VLH

News of Others

2011-12-17T09:17:00.001Z

Long-standing members of CARC will be very sorry to hear the news included in a recent Christmas letter received from Eileen Vaughan, XYL of Ron, VK6RV/G3FRV in Perth Australia advising that Ron is now seriously ill in hospital suffering from a major infection in both legs.

Both Ron and Eileen are life-members of CARC , Ron being a very active founder member and ex-Chairman of the Club before moving to Perth. He was also a former General Manager of the RSGB.for several years.

I am sure that all Ron and Eileen's long-standing friends in CARC will join me in sending them our very best wishes for Christmas and for a speedy improvement in Ron's medical condition.

73, de Derek Atter, Hon. President, CARC

Congratulations to Five New Advanced Licencees

2011-12-13T17:12:00.003Z

On behalf of the whole of CARC, congratulations to the following club members on passing their Advanced License Exam on 5th December:

David Davies (2E0DDG) who is now M0IDD
Barry Denyer-Green (2E0CEW) who is now M0HBM
Biton Wastra (2E0WAO) who is now M0WAO
David Wilde (2E0DPQ) who is now M0WID
Clement Holland (2E0CEZ) who's new call we do not yet know TBA

Thanks to Malcolm G3NZP for running the course and Ted G4TTY for assisting him.

Stewart/G3YSX

The Silent Listener - Falklands 1982 by D J Thorp

2011-12-12T22:31:00.003Z

I have just finished reading this excellent book on an aspect of the electronic warfare activies of a specialist army unit that operated in the Falklands conflict. To quote the publicity material:

On 2 April 1982 Argentina launched Operation Rosario, the invasion of the Falklands. The British, caught off guard, responded with Operation Corporate. Deployed alongside the rest of the British Army was a small specialist intelligence unit, whose very existence was unknown to many commanders and whose activities were cloaked in the Official Secrets Act. Trained during the years of the Cold War, the OC of the unit, D.J. Thorp, was tasked with providing electronic warfare support - the interception of Argentinean electronic and radio signals - allowing the British to be in real time receipt of enemy plans long before execution. For the first time in print, The Silent Listener confirms the existence and role of the Special Task Detachment during Operation Corporate and provides details of the deployment and operational role of a dedicated ground based electronic warfare (EW) weapons facility. It also details the development of electronic warfare during the Cold War period, including the establishment of a communications intercept site on East Island following the cessation of hostilities in the Falklands, and D.J. Thorp's top secret role in the investigation into the sinking of ARA General Belgrano. Complimented by previously unpublished photographs and classified documents only just released under the Official Secrets Act, The Silent Listener tells the story of the hidden Falklands War.

This book is currently available from RSGB as well as the usual online book retailers.

- Stewart/G3YSX

Touching TDR

2011-12-11T08:49:00.003Z

Time-domain reflectometry, the technology used to find breaks in cables and to characterize transmission channels at high frequencies, could find use as a touch application, according to an
interesting article in Technology Review.

http://www.technologyreview.com/computing/39036/

Researchers at the University of Munich and the Hasso Plattner Institute have used the decades-old technique (which Stewart, G3YSX has demonstrated at the club a number of times)
of determining the physical location of a discontinuity by touching the wires and observing the effect on the TDR measurement to identify the position that people are touching an object.

Reflections are caused by a change in capacitance as a finger approaches or touches the wire. Researchers claim that the technology could be used to sense touch in everyday items such as clothing and coffee tables, although I’m not sure how that could be useful.

Lightning-made Waves in Earth's Atmosphere Leak into Space

2011-12-11T08:46:00.002Z

At any given moment about 2,000 thunderstorms roll over Earth, producing some 50 flashes of lightning every second. Each lightning burst creates electromagnetic waves that begin to circle around Earth captured between Earth's surface and a boundary about 60 miles up. Some of the waves -- if they have just the right wavelength -- combine, increasing in strength, to create a repeating atmospheric heartbeat known as Schumann resonance. This resonance provides a useful tool to analyze Earth's weather, its electric environment, and to even help determine what types of atoms and molecules exist in Earth's atmosphere, but until now they have only ever been observed from below, but.....

http://www.scientificcomputing.com/news-DS-Lightning-made-Waves-in-Earths-Atmosphere-Leak-into-Space-120111.aspx

Waehurst Zero - The WW2 Radio Station at Wakehurst Place – a fascinating piece of local history.

2011-12-10T19:21:00.009Z

Fig. 1 Beautiful Wakehurst Place

The fight against Nazi Germany during WW2 produced urgent needs for rapid communications that was unparalleled in the history of warfare. Around the United Kingdom there were many small stations set up to monitor enemy radio traffic and pass intercept information on for decryption at centres such as Bletchley Park. There were also stations whose express purpose was to facilitate escape routes and provide essential information in case of invasion. One such station was located at Wakehurst Place in West Sussex.

The Special Duties Organisation, branch of the Auxiliary Units, was formed during WWII to co-ordinate radio communications and spying, in the event of German invasion. The section's personnel consisted of spies and out-station radio operators and the people who would operate the zero stations.

Spies would have been recruited from the general public; these people would write intelligence reports of any German troop movements, or anything else of interest they had seen. They would then pass the information on to a radio operator. A radio operator along with his equipment was classified as an out-station and they would in turn pass this information on to their local control stations.

A local control station was operated by three specially trained women of the ATS Auxiliary Unit, in an underground hideout known as a 'Zero Station', so-called because when the station's code-name was used it was always followed by the code suffix 'zero'. The purpose of a zero station was to receive coded information from the many out-stations in the surrounding area, passing on the details via a direct phone line to the Special Duties Headquarters at Hannington Hall, Wiltshire.

Special Duties Zero Station

This Auxiliary Unit Patrol and Operational Base is actually referred to in the records as Ardingly Zero but is in fact located at Wakehurst Place just North of the village of Ardingly in West Sussex. On the actual site, an area of about 40 feet by 30 feet, there had been signs of digging for several months last year, and then more recently the outline of what lay underneath, the station bunker, had been pegged out with white markers and an information board had been erected by the National Trust and Kew Gardens who jointly administrate these beautiful gardens.

Fig. 2 Information Board

The board provides some useful information on Wakehurst Zero, the underground bunker housing a hidden radio station that was part of a top-secret radio communications network designed to transmit intelligence information in the event of a German invasion. Unlike today, 1940’s wireless technology could only transmit across short distances (sic), and it is likely that the Wakehurst Zero Station relayed coded messages from outstations near the South Coast to Army HQ in Sevenoaks for decoding.

Fig. 3 Pegged out area showing outline of bunker

Staffing

It is believed that nine women officers from the Auxiliary Territorial Service (ATS) worked here in three shifts in uncomfortable conditions. The girls were billeted nearby. The work was so important that the station had no connection with the mansion, which had been commandeered by 1 Canadian Corps. Staff entered the bunker via a vertical entrance shaft hidden beneath a disguised manhole cover. At the far end of the bunker an emergency exit constructed from 3ft diameter concrete pipes and with a dog-leg bend designed to slow down pursuers - emerged in a former quarry known as Dog Kennel Pits. It can be seen today just beyond the path twenty or so yards to the south of the bunker.

The bunker itself comprised the entrance chamber under the manhole cover, a main chamber containing the radio equipment, a few pieces of furniture and beds for the operators, and a third chamber which housed a chemical toilet and storage space.

Fig. 4 Escape exit nearby

Radio aerials from the bunker were channeled into the bark of three adjacent oak trees and connected between the trees canopies. The channels and remnants of the wire remain visible today, sixty-five years later, although you do have to look hard to spot them.

Fig 5. Aerial wire running vertically immediately to left of tree trunk

In 1944 Wakehurst Zero was decommissioned. The contents were removed and the entrance sealed up.

Sadly, few other details are known about the Wakehurst Zero/Relay Station and those who worked here. The stories of many who played such a key role in the war effort were often not recorded. This is why its survival is an important way of remembering those who served here and at similar sites. The National Trust and Kew at Wakehurst are to be commended for working together in this way to ensure the site can be appropriately cared for and interpreted in the future.

This interpretation project was inspired by a local person, Eleanor Springall, who sadly died in 2011, prior to its completion.

John Longhurst G3VLH

The Crawley Round Table, 11th September, 2011

2011-12-07T09:45:00.016Z

This article is based on a report by Alan Melia, G3NYK, was first published in "GHz Bands", RSGB RADCOM Nov 2011.

"This Year's Crawley Microwave Round Table took place on 11 September at the Crawley Amateur Radio club premises in the Tilgate Forest complex, on the south side of Crawley. Despite the clash with Weinheim, which was attended by a number of the usual attendees, 31 people signed the attendance book and there was many a vigorous discussion during the morning “eyeball” session which included the usual table-top sale of bits and pieces.

Look what I've found!

In parallel, the annual microwave Construction Contest was in progress and was well supported, with 9 entries on show that the panel judged to be of a very high standard with exhibits ranging from a very ambitious 5-band transverter covering 1.3Ghz to 10Ghz through to a nicely made SSR Synthetic radar receiver using chip components entered by CARC member David Davis, 2E0DGG recently constructed as his Intermediate exam project. The G3VVB Construction Contest trophy was won by Jeff Easdown, G4HIZ for his compact and well thought out 13 and 9cm band transverter.

After a lunch that included as usual, bacon butties, hot dogs and sandwiches, the formal proceedings were opened by the CARC President Derek Atter, G3GRO who invited Allan G8LSD to present the G3VVB trophy to Jeff G4HIZ.

Formal Proceedings Opened by G3GRO

Constructors Contest Judges

Allan, G8LSD presenting the G3VVB trophy to Jeff G4HIZ.

The presentation was followed by 3 interesting talks, the first of which was given by Mike Scott, G3LYP who described his successful modifications to the W1GHZ multi-band transverter for use on 13cm and 9cm. He also described his efforts to produce hairpin PCB filters, in the UHF range, with his 'kitchen table' PCB production system, including moving the pass band down by clamping a piece of PTFE over the copper tracks. He has reported his subsequent success with the receiver on the UK Microwave Yahoo Group.

Mike Scott, G3LYP

3.4Ghz Transverter by G3LYP

Making one of the longer journeys to Crawley was Chris Bartram, GW4DGU, who described his design for a relatively cheap no-tune 10GHz transverter using a relatively simple PLL with a VCO running in the 5GHz range locked to a stable external 100MHz source. Chris's target was to produce a unit that should come in at about half the price of a commercial transverter. He demonstrated the stability and quality of the tone on a prototype unit transmitting CW across the lecture room to Andy Talbot's 10GHz system, which had been entered in the Construction Contest. Chris also demonstrated the effect he noticed at home caused by the plasma in the fluorescent lights inducing a hum on the note. When the lights were extinguished the T9 note returned. There was considerable interest at the thought of a cheaper entry to the higher bands and the inevitable question was whether it could be made to work at 24GHz. The guarded answer from Chris was “I think so” (or similar words from the depths of his beard!).

Chris Bartram, GW4DGU

The final talk was a double header from CARC members, Derek Atter, G3GRO and Peter, G4FYY. They described some developments of a very simple diode power meter idea from DL5NEG based on a simple SMD diode sensor with a DVM read-out in DC millivolts which is read in conjunction with very detailed calibration charts going up to 6.0GHz The joint project was stimulated on Derek's part by the tears shed when he realised that he had just burned out the sensor head for his HP435 power meter and found the cost for a surplus replacement was about £400. They determined to make a simple, cheap, everyday power measurement device accurate enough for most amateur microwave applications. Several copies of the DL5NEG diode sensor head design were built to confirm the repeatability and performance up to 6GHz before setting about making it into a full indicating power meter, without the need for a digital multimeter and attendant look-up tables. Derek's version is a passive unit with moving coil meter display using serial diodes to produce several break points to achieve scale linearity with a standard meter without specially marked-up scales but with an FSD on the most sensitive range of only 3mW while still retaining the option of using a DVM on the DC output plus a calibration chart to measure power RF down to -30dBM. The meter has 4 switched calibration correction points for frequency up to 6 GHz rather like the HP435.

Peter meanwhile developed a PIC-based measuring system with an LCD display and an amplifier to aim at a sensitivity target of -50dBm. He showed a demonstration model which is almost there but still has an offset problem; he would also like to improve the linearisation algorithm. These problems brought forth a number of suggestions from the audience.

Peter Head, G4FYY and Derek Atter G3GRO

G3GRO/G4FYY Power Meter and Sensor Head.

It was good to meet old friends and to see that Derek, despite being wheelchair bound, is still taking a very active interest in RF stuff. All in all a very enjoyable event, once again and many congratulations to the organisers. If you didn't attend you missed a great event; put it in your calendar for next year.

73, to all.. Alan, G3NYK

Acknowledgements © RSGB 2011, reproduced here with permission
Photographs courtesy of Chris G0FDZ

Amateur Radio History From Across the Pond

2011-11-30T11:27:00.000Z

Two more videos on amateur radio times past, this time from our American cousins.

http://www.youtube.com/watch?v=P0igVLrt3uY

http://www.youtube.com/watch?v=bK-1j9UxT-I&feature=related

CARC Programme 2011/12

2011-11-29T12:21:00.001Z

Issue:	December 2011
Meetings:	Every Wednesday Evening commencing 8.00 pm
	Every Sunday Morning from 10.30 a.m.
Main Meetings:	4^th Wednesday in the month starting at 7.45 for 8.00pm (unless otherwise advised.)

MONTH	DATE	TOPIC	BY
November	Wed 30^th	HARC/CARC Challenge. This promises to be another fiendishly plotted but fun contest by our friends from Horsham ARC. Do come along to take part in this entertaining evening.
December	Fri 2^nd Wed 7^th	CARC Annual Fish and Chip Supper – put it in your diary! Introduction to Microwaves Part 2 by Derek G3GRO. A follow on to Derek’s excellent talk earlier in the year.	Derek Atter G3GRO
January	Wed 25^th	Annual General Meeting Another date for your diary!
February		TBA

Club Opening over Christmas Period

2011-11-29T10:16:00.002Z

At the committee meeting last night, we discussed the Christmas 2011 opening times which are a bit problematic this year due to the days of the week on which Christmas Day and New Year's day fall.

Here is the plan:

Sat 24th Dec Christmas Eve there will be a club net at 8pm on GB3MH

Sun 25^th Dec CLOSED

Wed 28^th Dec OPEN as normal

Sun 1^st Jan New Years Day CLOSED but here will be club net at 11am on GB3MH

Normal service from 4^th January 2012

If any key holder wishes to open on Christmas Day or New Years Day they are of course welcome to do so, and should let rest of the club know.

Stewart/G3YSX

The Listeners

2011-11-26T18:18:00.003Z

Trevor, M5AKA, noted on the GQRP list, the following interesting video of a TV program called "The Listeners" from 1979 that can now be watched on the web. See  http://www.eafa.org.uk/catalogue/5108 

Enjoy

Stewart/G3YSX

Some Interesting Presentations

2011-11-20T21:58:00.004Z

Derek, G3GRO, suggested that other CARC members may be interested in two presentations that are on the West Carleton Amateur Radio Club web site.

The first, http://www.wcarc.on.ca/caution42.html, is a powerpoint presentation entitled Ground Mounted Vertical Antennas and is by Doug Leach VE3XK.

The second is http://www.wcarc.on.ca/caution8.html is a lecture by VO1NO entitled Dr. R V Jones and the Battle of the beams.

Just looking at the titles on the WCARC presentation page http://www.wcarc.on.ca/presentations.html there are a lot of presentations that will be of interest to CARC members.

RSGB Advisory Group Report

2011-11-13T21:00:00.002Z

The much talked about RSGB Advisory Group report has been leaked to the Internet.

The document was the base underpinning the November 2011 Radcom article outlining the EGM vote, but was not intended for member consideration.

However it has been posted on a number of web sites and must be considered effectively in the public domain.

The 77 page report may be downloaded (for example) from : https://anonfiles.com/cdn/1321109197747.pdf

It is my personal view that as a think tank report the document is actually not bad. It will have taken a lot of work to put together, and we should thank those that put gave their time to produce it. At least they made an attempt at some alternative approaches to moving the RSGB forward.

Like all such reports there are bits that are good and there are bits that are bad. There are bits that I agree with, there are bits that I do not agree with. They will not be the same bits as others (dis)agree with. However it is a starting point and it is worth reading so you can make your own mind up about possible ways forward for the RSGB.

Stewart/G3YSX

The PA0RDT output transistor

2011-11-08T20:13:00.002Z

A short note from PA0RDT that was posted recently on the LF reflector may be use to readers building one of his active antennas:

"On an other note, instead of the trusty 2N5109 a BFQ19, a modern rf transistor, can be used.
It gives slightly better IMD figures in this circuit, especial at lower supply voltages."

GB3MH and GB7MH

2011-11-08T19:55:00.002Z

The following was a report to HARC on our recent talk on GB3MH and GB7MH. This was written by Alister, G3ZBU and we thank him for permission to reproduce it here.

Your hon sec went along to our friends in Crawley for their monthly talk which was on the Ashdown Forest Group's repeater GB3MH, which is located at a church in Turner's Hill. This 2m repeater is co-located with a 70cm D-star repeater and they share the same aerial;
the aerial is a 2m/70cm co-linear cunningly disguised inside a flagpole. Power is about 5W ERP, and the aerial height is about 600ft above sea level, so it covers from the North Downs to the South Downs. Coverage is not so good to the West.

What is interesting about the 2m repeater is that it has an Internet link to the rest of the world. It can be used as a normal repeater for local contacts on 145.625MHz/145.025MHz, and it gereates a Morse 'K' between overs. However, if you have a DTMF keypad, you can make contacts all round the world using either Echolink or IRLP modes. To access an Echolink node, press star/asterisk/* before the node ID, e.g. to access an EchoTest node, press *9999.

Echolink nodes include mobile phones, so it is possible to access someone's mobile phone. We had a demo where a phone runs an 'app' that has a soft PTT button on the touchscreen, so it makes the phone work in simplex mode. To use a phone, or computer for that matter, you have to send off a copy of your licence and become registered.

IRLP is a mode where the two ends of the link must be done by amateur RF. One doesn't need special registration because using RF sort of infers that one is licensed, or maybe a pirate...

When linked, the 'K' signal is replaced with a 'courtesy tone' ( 3 tones rising or falling in frequency ). If you hear the 'K' you know the linking has been undone! To unlink, key in 73.

Dave 2E0DDG accessed repeaters around the world but no-one replied! Possibly it was very early in the morning in ZL-land! He impressed upon us the operating procedures to be used: always listen first, then ask if the repeater can be linked. Of most importance is to leave a large pause between transmitting to allow all other repeaters to change from tx to rx. This can take up to 3 seconds if the end point is on the other side of the planet. Without a large pause, the repaters can end up in silly states e.g. locked in transmit!

The reader may like to read an article originally published in the Feb 2010 issue of RadCom by G4ULF.

The aerial had to be professionally erected, and considerable expense went into all the legalities of planning permission. It cost something like £2,000 to get the kit on the air. Most of the electronics was kindly donated. Annual running expenses are mainly for internet access and electricity, as the site rent is a 'peppercorn' rate.

The tone levels are not quite correct as the 'K' is far louder than the received audio. If enough people complain then this may get sorted out.

Response from Phillip Brooks (G4NZQ) and Charlie Morrison (GI4FUE)

2011-11-05T15:46:00.004Z

Following an email exchange with Don (G3BJ) the RSGB GM in which I noted that I was awaiting an answer from Phillip Brooks (G4NZQ) and Charlie Morrison (GI4FUE) to the letter that we had twice sent them (http://carconline.blogspot.com/2010/10/questions-to-prospective-rsgb-board.html) I have received the following with authority to distribute it.

Whilst it is worrying that it was so difficult to solicit a response, I feel that it is positive that G3BJ pushed the issue on our behalf and that Phillip and Charlie responded in the end.

Stewart/G3YSX

Response Starts:

Stewart Bryant
Chairman Crawley ARC

Dear Stewart

We have jointly discussed the letter below posted on discussion groups, and have included our response, which we hope is helpful, against each point.

Phillip Brooks, G4NZQ
Charlie Morrison, GI4FUE

Dear Sirs,

I am writing on behalf of the Crawley Amateur Radio Club. You are a candidates for election to the RSGB Board. We have read your statement in RadCom, but we have a number of questions that we wish to put to you to factor into our decision making before voting in the Board Election.

To make this an open process I have posted the questions on the CARC Blog (carconline.blogspot.com), and have requested that Southgate ARC (http://www.southgatearc.org/) post them on their Newswire service. We would request that you copy your answers to those two web services, or that you request that I do so on your behalf.

1) Many elements of the RSGB decision making process take place behind closed doors with little effort to consult with members before a final decision is made. In this modern, Internet connected era, there are many ways to solicit wider input from the community. If (re)elected what steps will you take to ensure that the RSGB Board gathers wider input as part of its decision making process?

There have already been discussions about using our website for e-surveys of members views (as was done in the Amateur Radio survey last year). We support this approach, and in our view it is implicit in the way that the Interim Board would handle member consultation on the changes necessary to the Society to recover from the current situation.

2) The sub-committees of Board, for example the ETCC is composed primarily of unelected members. What steps will you take to ensure that the membership of sub-committees is more representative of RSGB membership, that they are accountable to the membership for their decisions and the that decision making process is transparent and includes an appeal mechanism?

At present, members of committees (but not the chairman, and excluding the Management Committee) are appointed on the recommendation/decision of the committee. To a certain extent this recognises the need for specific experience in the specialist areas – we don’t want “badge collectors” without relevant skills. But you will have noted in the past (e.g. EMC Committee earlier this year) that adverts are placed in RadCom inviting those with relevant skills to express an interest in joining committees. Sadly in general the response is minimal. We would like to see Chairmen more accountable to the Board in the future about the business and activities of their committees.

3) The RSGB recently increased its membership fees at a time when members are under considerable financial stress. What measures do you feel the RSGB should take to ensure that it does not place additional financial burdens on its membership during the current financial crisis?

That is exactly the role of the proposed Interim Board. The Advisory Group took the view that membership fees were already too high, but we need to resolve the current financial pressures before we can address that. Despite commentary from the “vote no” camp that there is not a crisis, there is, and steering a way through the current financial problems will require skill and aptitude.

Stewart Bryant
Chairman Crawley ARC

Posted by g3ysx at 10:44 PM

Response Ends

Ernie Edwards,2E0EWE

2011-11-03T08:23:00.001Z

Most of the regular attendees at the CARC regular Meetings will by now be aware, that with great sadness we have had to report the recent passing away of Ernie Edwards (2E0EWE). A long term supporter of the Club, Ernie had been until recently despite an increasing struggle with ill-health over the past few years, a very regular attender not only at CARC club meetings but also an attendee at other clubs such as the Horsham Club and at rallies like Kempton Park.

Ernie was a skilled tool maker (we believe at Edward's High Vacuum Co.) and came into amateur radio fairly late in life so he had to work hard at passing his exams, but his quiet persistence and enthusiasm paid off and he acquired his 2E0 callsign which I think gave him a great deal of satisfaction and pleasure in the companionship of the Club membership.

We extend our condolences to Ernie's Family.

The RSGB EGM

2011-10-31T18:11:00.004Z

For those Club members who are in the RSGB, there are a number of places that you can information to help you understand the issues that have lead to the EGM on the 19th November and the proposals that have been put forward by the current board.

Series Four Episode Twenty-Two of the ICQ Podcast has been released by Martin (M1MRB) and Colin (M6BOY) and includes discussion of the issues facing the RSGB EGM annoucement. Ex RSGB Technical Director Leslie Butterfields (G0CIB) joins us to help to understand the proposals. This can be found at http://preview.tinyurl.com/5rbfez5. You need to listen about an hour into the podcast to get to the interview.

Martin and Colin have also released Series Four Episode Twenty-Three of the ICQ Amateur / Ham Radio Podcast, RSGB President EGM Answers, where Dave Wilson (M0OBNW) addresses issues raised in the previous podcast and a number of reader letters. Questions asked covered The New Board, Transparency, Communications, Bletchley Park & RSGB4FUN, Licensing, RADCOM, Peter Kirby, Membership and the EGM Day. This can be found at http://preview.tinyurl.com/6fynu8c .

There is the RSGB Governance forum that is work looking at (http://rsgbdata.net/yabb/YaBB.pl?board=general).

There is also a yahoo group whiteroseradiouk at groups.yahoo.com/group/whiteroseradiouk/ that you may wish to join.

Dave Wilson, the RSGB President has also written a second note to members here http://www.rsgb.org/news/articlelinks.php?id=0218 which addresses a number of the questions raised.

I am assured by Don Beattie, G3BJ that there is nothing that prevents prospective members of the Interim Board from answering questions.

There is information that can help us make a decision about our preferred way forward for teh RSGB in these very difficult times. Those of us that are members need to make our own minds up. It is important is that we all think carefully about the issues and use the information available to decide which way to vote. Given the importance of the issues that face the RSGB it is important that we do all vote, and vote by the 16th November. Voting can be via proxy, via the voting form in RADcom and via the Internet.

There are a number of people that I know are considering leaving the RSGB. Speaking personally, I was very disappointed with the organization that the RSGB had become. However, I think that the UK amateur radio community needs an RSGB, and the best way forward is to engage with the existing and prospective RSGB leadership and help to shape the organization such that it is the organization you want it to be. The whether we need an RSGB, whether you want to be part of the RSGB, what the shape the new RSGB needs to be, and which way to vote, is of course something that each of us has to form their own opinion on.

Stewart/G3YSX

Another Foundation Course : Five Students, Five Candidates. Five Passes.

2011-10-29T22:43:00.006+01:00

Over the weekend 15^th/16^th October your current training team ran their seventh course at Hut 18, Tilgate Recreational Park. This time it was for five budding hams to take their first step into the world of amateur radio by obtaining a Foundation Licence, but we are also holding a series of seminars during November for those who wish to take the Advanced Level examination on 5^th December.

Following a fairly intensive set of practical assessments and tutorials all were successful in gaining a pass certificate.

Good luck from your instructors and enjoy the hobby.
Malcolm Harman (G3NZP)

Meet the RSGB - Saturday 22nd Oct

2011-09-25T22:47:00.001+01:00

An Invitation to:

Meet the RSGB

Normandy Centre, Denne Road, Horsham

1200 until 1700 hrs on 22^nd October 2011

In co-operation with

SCARF

(Southern Counties Amateur Radio Forum)

arranged by Mike Senior, G4EFO

RSGB DRM for Sussex.

Programme:

12.00 - 2.00pm meet have a drink and ploughmans lunch ( food by pre order only ) , visit other clubs represented.

2.00 - 3.00pm President of the RSGB: Talk and Q&A

3.00 - 3.15 comfort break

4.00 - 4.15 Mark Allgar from HQ: Talk and Q&A session

4.15 perhaps any final socialising

Hall to be clear by 5.00pm.

Cloth Cable

2011-09-16T23:14:00.000+01:00

The following clever method of creating a retro look was posted to the QRP-L list and is reproduced with the permission of the author, Chris K4FH.

I've always liked the look of cloth cable over plastic insulated cable. I bought a pair of head phones that had a retro look and it used a cloth cable.

I've formulated a way I can simulate the look using paracord.

1) Cut a length of paracord

2) Using the butt end of a drill bit, insert the bit into the cord and use a lighter to singe the cord.  This keeps it from unraveling.  I use the bit to keep the cord from closing up.

3)  Run as many strands of #22 stranded inside the cord as you need.  

4)  Solder those to the connector

5)  Use the strain relief in the connector to hold onto the paracord.

After you get one end done allow the cord to relax and then do the other end.  This keeps it from being bunched up.

It is not a perfect replication of look and feel.  You can hold it and tell there is wire inside and room for more wire.  In 550 there is not much room for more than 3 wires.  If you want to make something bigger
try the larger dacron used as antenna rope.

I chose the silver ends with the springs because I wanted a nice look. I also made a cable for my J-38.  Since one end uses terminals I used heat shrink to bind the lead wires (with terminals) to the cord and make it look nice.  

In the audio cable in the pic I used a single pair of spare wire I pulled out of some CAT-5.

With this method you can make any length you want with any number of wires you need.

73,
Chris k4fh

Military Matters

2011-09-16T22:58:00.000+01:00

As some of you may know, V.M.A.R.S, Vintage and Military Amateur Radio Society are a group of like minded people who have an interest in preserving and refurbishing military and civil radios. Many of their members have fully fitted vehicles with all their radio equipment mounted within. These vehicles can often be seen at Fairs and Shows throughout the country and their owners are only too glad to answer any questions you may have about their kit.

On the 10^th September they held an operating day near Gatwick Airport in the grounds of a house called Hunters Moon. The owner of which is also a member and a licensed operator. As I had the time I visited the site to see what was going on as my knowledge of Military Radios is limited. I must add that I only located the site after ringing the organiser.

I was welcomed by the site owner who explained what the attendees were doing and where to park. A few show vehicles and tea tent were located by the entrance which made the site more inviting. Further up the field was a line of wire dipole antennas and another radio equipped vehicle. At the end was a large tent for sleeping and cooking for some of the ‘crew’. To the right was a wonderful display of military radios past and present all set out on various tables and in two vehicles. Perhaps sets with names like No9, No18, Larkspur and Clansman amongst many others would have brought back memories for some of you.

A few of the display vehicles on show, all fully kitted out. Yes, even a 6 pound anti-tank gun.

The wonderful display of radios on the tables, the army tent used for sleeping in, the Landrover overloaded with radio kit and finally an Austin Champ with a full Larkspur set up. Note the Loop Antenna!

During my time there I asked many questions regarding the use of the radios and discovered that most of them will operate on the amateur bands easily. Some of the radios are not as easy to operate as ours but will perform very well. The quality of build is probably better in many respects as they have to endure harsher conditions than ours. They could be operating in the Artic or a steamy jungle and are expected to perform with the same efficiency.

A few other members arrived and started to set up their antennas and rig layouts. In the four hours I was there only one other ‘outsider’ looked in at the event, pity, because I felt that a bit more support from outsiders would help them along.

I enjoyed increasing my knowledge and made to feel very welcome by the members.

Give it a try next year.

BrianG

2E0MZB

CARC Programme 2011

2011-09-11T09:05:00.001+01:00

Issue:	October 2011
Meetings:	Every Wednesday Evening commencing 8.00 pm
	Every Sunday Morning from 10.30 a.m.
Main Meetings:	4^th Wednesday in the month starting at 7.45 for 8.00pm (unless otherwise advised.)

MONTH	DATE	TOPIC	BY
September	Wed 28^th	FFT’s and the PC in your Shack. An overview of the new wave of mainly low cost computer-based test instruments, including Vector Network Analysers, oscilloscopes and spectrum analysers.
October	Wed 12^th Wed 19^th	GB3MH A presentation on our newest and technically most advanced local repeater. This covers the site acquisition history, hardware and installation, with an explanation in simple terms of the network architecture and the way to access/operate through EchoLink/IRLP. Excalibur, SDR-IQ, broadband loop, and novel applications.	Malcolm G3NZP, David 2E0DDG & Richard G4ANN Mike Underhill G3LHZ
November	Wed 23^rd Wed 30^th	Technical Systems in Air Traffic Control in the UK HARC/CARC Challenge. This promises to be another fiendishly plotted but fun contest by our friends from Horsham ARC. Do come along to take part in this fun evening.	Alan O’Donovan G8NKM
December	Fri 2^nd Wed 7^th	CARC Annual Fish and Chip Supper – put it in your diary! Introduction to Microwaves Part 2 by Derek G3GRO. A follow-on to Derek’s excellent talk earlier in the year.
January	Wed 25^th	Annual General Meeting Another date for your diary!

CRAWLEY ROUNDTABLE

2011-09-04T18:02:00.001+01:00

The 2011 Crawley Roundtable is on Sunday September 11.
As usual we will be running the UK Microwave Group annual construction contest for the G3VVB trophy. Please do bring along your constructed equipment and enter the contest. Entries do not necessarily need to have been constructed during the last year.
Do come along and support the construction contest and hear the talks.
Below is the finalised timetable:

Microwave Round Table - Sunday 11th September 2011

          Crawley Amateur Radio Club

10:00AM   Venue opens

12:00     Construction contest judging commences

13:00     Lunch (rolls, sandwiches, tea/coffee available)

13:30     Opening address by Derek G3GRO

          and the results of the construction contest

14:00     'An Experimental Transverter for 3.4 GHz' or "Fun with filters"

           - by Mike Scott G3LYP

14:45     'An Examination of Local Oscillator Noise'

           - by Chris Bartram GW4GDU

15:25     Break (tea & coffee available)

15:45     'A simple Diode RF Power Meter usable from HF to 6.0GHz'

           - by Peter Head G4FYY and Derek G3GRO

16:30     End of meeting

If you need further information, contact Derek Atter G3GRO or Chris Whitmarsh G0FDZ

 





Access to Site:



The access road into Tilgate Recreational Centre

and the CARC Clubhouse (Hut18) is via the sliproad at the new traffic lights on

the southbound carriageway of the A23 (Brighton Road), just south of Crawley

heading towards Brighton, and about 200m from the Broadfield Football Stadium

roundabout which is well signposted.
The Clubhouse is accessed via a fairly narrow track for about

200m. Watch out for anti-traveller caravan chicanes then turn right at the 3rd

sleeping policeman!

· 

More Directions:   CARC Directions
· 

Roundtables:   General Info
Click here if

you do not see the main microwavers.org menu bar on the left

GB3MH

2011-08-28T22:08:00.003+01:00

The GB3MH 2m analogue and Echolink/IRLP Repeater at Turners Hill was commissioned on 26th August at 18:00. This is working well as a local repeater but we are having some technical problems with the DTMF Echolink/IRLP signalling and the audio pass through from local RF to Echolink/IRLP. Work is underway to debug the problem and we will post an update when these issues are resolved.

The Technical details are:

CALLSIGN	GB3MH
BAND	2M
CHANNEL	RV50
OUTPUT	145.6250 MHz
RX1	145.0250 MHz
MODE	ANALOGUE
QTHR	IO91WC
LOCATION	W SUSSEX
NGR (view)	TQ337354
REGION	SOUTH-EAST
CTCSS	88.5 Hz
KEEPER	G3NZP
IRLP NODE	5877

The projected coverage is shown below.

Reports are appreciated and may be added as comments to this blog entry.

Stewart/G3YSX

NEW MEMBERS EVENING

2011-08-28T21:49:00.007+01:00

CARC Meeting 27th July 2011

At the July Committee Meeting it was suggested by our training instructor Malcolm Harman G3NZP that we should run a "show and tell" evening at which all recent Intermediate students bring along their radio related project and spend 10 minutes or so explaining reasons for choice and how it works. The committee agreed that this was a good idea and it was left that Malcolm should liaise with the members concerned.

Part of the RFC /RSBG Intermediate Exam involves a whole series of practical assessments of which the Radio Related Project is just one. Nevertheless it's the most interesting because it's down to the student to agree with the Instructor a sufficiently challenging construction task to be assessed as part of the course work.

This would accomplish two things. Most importantly it would offer an opportunity for others to get to know our new members better and personally welcome them into the club. Secondly it will provide a very interesting evening of mini-talks.

We had at least three Intermediates confirmed and two possibles, dependent on work commitments, each kindly agreeing to make a short presentation on a project they have built.

On the evening we had three new members, Ian Coulson, David Davies and Barry Denyer-Green. Two other members who had hoped to be available and to give presentations, Biton Walstra and Graham Parsons, had work commitments and sent their apologies. Hopefully they will have other opportunities in the coming weeks.

The Valient 3 - Ian, David and Barry

Ian bravely started the ball rolling with a small FM receiver/tuner kit that he had built. This covers 1.5 to 100 MHz and after a few initial problems and “a prod with a sharp stick” burst into life. Ian explained that amongst the difficulties that he experienced were that the kit was now obsolete and the amount of backup from the supplier was pretty limited. However he has spent more than half a century using a soldering iron and the practical aspect held no real fears for him.

Next up was David Davies. He described a low-ish cost alternative to the Kinetics SBS-1 radar receivers that currently retails for around £400. David works at Redhill Aerodrome and there was a need for three such receivers in order to receive the ADB-S (Automatic Dependent Surveillance Broadcast) signals from approaching light aircraft and to triangulate their bearings. He found a kit designed and marketed by a German amateur which sold for some 50 Euros and decided to give this a try. The result was a very neat and cost-effective little unit, which plugs into the USB port of his MacBook. Operating on the appropriate 1090MHz channel frequency, and running the appropriate software which includes PlanePlotter, (a program for Windows that provides a radar-like display of aircraft derived from ADS-B position reports), and with a makeshift antenna David was able to give a live demonstration of the receiver with the screen rapidly filling up with aircraft ID signals. Fascinating.

David's radar receiver

David with the read out from his radar receiver

Barry, last but by no means least, had two projects for us. Starting with his PP3 - powered solid-state regenerative receiver this was a very neat 3-band radio covering 80, 40 and 20 metres, and will have brought back happy memories to many of us who similarly cut their teeth on these simple but effective designs. Barry spends quite a lot of his working life staying in hotels and this little receiver with a length of wire strung out of a window keeps him in touch with the world.

Barry's receiver and signal generator

Barry’s second piece of home brew was an RF signal generator with switched bands and housed in a small Eddystone-type aluminium enclosure. Very useful for aligning and fault-finding on other receiver projects.

Barry with his signal generator

This is only a very brief write up of the various projects and in no way does justice to the amount of work that these brave chaps put into building and de-bugging their projects.

Thank you, Ian, David and Barry for your excellent presentations, which made for a most enjoyable evening.

John G3VLH

Electronic tutorials

2011-08-21T10:05:00.002+01:00

Adrian, G3VJM, draws our attention to an excellent site on basic electrical and electronics theory. This site looks like it will be useful to those studying for their Advanced License.

Based in Northern Texas, OpAmp Electronics delivers a series of free, comprehensive, and detailed tutorials of the basic fundamentals of electricity and electronics authored by Tony Kuphaldt. Among the 59+ chapters on DC, AC, Semiconductor, and Digital theory to guide you through your studies or electronic projects, please feel free to navigate the different segments of our site for additional electronics assistance.

The electronic tutorials found on this site were written by Tony Kuphaldt, and can be found at http://www.opamp-electronics.com/tutorials/index.htm

Another Active Antenna

2011-08-14T10:15:00.007+01:00

Ron, G4GXO recently drew the attention of the QRP community to an engineering report released by the US government describing a Voltage Probe Antenna (VPA) Design 5 kHz to 500 MHz. The design dates back to April 1973 and was produced by GTE.

The objective of the overall development of the Voltage Probe Antenna (VPA) was to produce a miniature, mast mounted, omni-directional antenna that would operate over the band from 5 kHz to 500 MHz for communications reception. In addition, it was desired to optimize the antenna at 150 MHz and 400 MHz.

The report of the report can be found at:

http://oai.dtic.mil/oai/oai?verb=getRecord&metadataPrefix=html&identifier=ADA030178

The report itself is at: http://handle.dtic.mil/100.2/ADA030178

As Ron reports, "The images but they are all "washed out" by the copying process. However, there are some illustrations of the test range which suggest a short pole (about a couple of feet high) onto which the antenna is mounted. At the base of the pole is a ground pane to simulate salt water - presumably this aerial was for covert use when the submarine was at snorkel/periscope depth. The aerial element appears to be small, probably around 30cm high by 15cm diameter. There is also mention of the "probe" being a bi-cone, a wideband VHF/UHF antenna - note that one of the design objectives was to provide LF to UHF coverage optimized at 150MHz and 400MHz; VHF aviation/marine and UHF aviation bands?"

The circuit is quite interesting since at first glance it looks like a conventional FET input active antenna similar to the PA0RDT design that we are all familiar with, with the modification that an MMIC is used in place of a transistor in the second stage. However on a second look (an reading the text) I see that there is an interesting subtly to quote from the report:

"The amplifier consists of two active stages; the first stage consists of a low-
noise field-effect transistor used for active impedance matching, and the second stage consists of a low-noise microwave integrated circuit that provides actual voltage gain.

"The field-effect transistor is operated in a cource-follower(sic) configuration with an additional gate~to-source capacitor C2 added to alter the input impedance characteristics and to improve high-frequency performance. At low frequencies where the gate and source of the transistor have an in-phase voltage of nearly equal magnitude, capacitor C2 essentially disappears from the circuit as very little voltage appears across it. This provides a very high impedance at lcw frequencies that approaches 1.5 megohms shunted by 4 pF.

"At high frequencies where the voltage on the source of the transistor begins
dropping and the phase shift becomes important, signal voltage begins to develop
across capacitor C2. This provides a signal path around the first-stage transistor Q1. As the frequency goes progressively higher, the impedance of capacitor C2 drops quite low until the input impedance of the amplifier approaches that of the second-stage amplifier A1. At high frequencies (above 100 MHz), the first-stage amplifier Q1 adds very little to the performance of the circuit.

"Diodes CR1 and CR4 provide burnout protection for the input of the amplifiers. Resistor R3 is provided to suppress transients on the output cables so the voltage limitations of the output capacitor are not exceeded."

The amplifier performance specifications, measured in a 50-ohm test system,
are given in the report are shown below:

Frequency Range 5 kHz to 500 MHz
Gain 11 dB +/- 1dB
Noise Figure 8dB at 150 MHZ and 400 MHZ
Output Power
(1 dB Compression) 6 dBm
Intercept Point
(Third order) 17 dBm
DC Power 45 mA_at +12 Vdc
15 mA at -12 Vdc
Physical size 1x1x0.5 inches

It would be interesting to redesign the antenna using more modern components for use as a wideband scanning antenna.

Stewart/G3YSX

Sine wave Oscillators

2011-08-14T10:10:00.002+01:00

Steve G0XAR recently posted a pointer to a very interesting Texas Instruments tutorial on the threory of sine wave oscillators on a course materials page at University College of Santa Barbra.

The paper can be found at:

http://www.ece.ucsb.edu/courses/ECE137/137B_S11Theo/oscillators.pdf

CARC Training Courses

2011-08-12T08:57:00.003+01:00

Malcolm, G3NZP reports that currently he has two. possibly three, interested candidates for the proposed Foundation Course now set for weekend 15th/16th October, commencing 09.30 at Hut 18, Tilagate Recreational Park, Crawley. Closing date for entry Friday 23rd September. Please put any other candidates in touch with Malcolm.

Malcolm also proposes to run an Advanced Examination on Monday 5th December at 19.00 which will be preceded by four of five weekly seminars to help bring students up to speed. Application for the exam to Malcolm by 7th November.

Malcolm G3NZP is QTHR and can be reached on 01342 713573.

Stewart/G3YSX

FUNcube Dongle as a Radio Telescope

2011-08-12T08:49:00.002+01:00

A number of club members have a FUNcube dongle SDR receiver and so I thought that I was draw attention to an interesting post by M0TFO on funcube@yahoogroups.com.

M0TFO draws attention to a Radio Astronomy paper describes the use of the AMSAT-UK FUNcube Dongle Software Defined Radio as part of a Radio Telescope. In the paper Dr David Morgan of the British Astronomical Association Radio Astronomy Group (BAA-RAG) describes how he used the FUNcube Dongle as the heart of a Radio Telescope operating on 1420 MHz.

He concludes that "A newly available SDR component has been shown to be very capable of acting as the heart of a simple and inexpensive three component radio telescope.".

You can download the paper `Experiments with a Software Defined Radio Telescope' by Dr David Morgan at http://www.britastro.org/radio/projects/An_SDR_Radio_Telescope.pdf

Some interesting, but more general radio astronomy projects can be found at http://www.britastro.org/radio/projects/otherproj.html

I have yet to explore the group, but BAA-RAG Yahoo Group http://groups.yahoo.com/group/baa-rag/ looks as if it might be worth joining.

Stewart/G3YSX

Military Maritime Communications

2011-08-11T23:56:00.003+01:00

CARC MEETING 29th June 2011
By Dr Andrew Gillespie Technical Director Thales Communications

Reliable networked communications to maritime platforms represents a significant technical challenge. Dr Gillespie’s presentation focused on the problems faced in providing Web Services over low bandwidth, intermittent bearers such as HF and V/UHF radio.

Andrew began by outlining the background to HF communications and its present needs in military and professional applications. Historically HF communications has been widely used by military, commercial, government, aid and relief organisations. However, the end of HF as a usable technology has been forecast for many years. The advent and growing usage of satellites at one time seemed to further hasten the demise of high frequency communications. To misquote Oscar Wilde “news of its death is greatly exaggerated”.

For all its long distance capability HF is susceptible to noise, interference, ionospheric variabilities and disturbances and other limiting issues that are not present in satellite communication. However, the major drawback of satellite for military comms is cost. Satellite time and bandwidth are expensive, and alternatives are needed to provide a common platform for member states, in NATO, for instance.

For some years there have been other alternative HF networking protocols in use. Some of these rely upon Automatic Link Establishment (ALE ) using the FED-1045 or MIL-STD 188-141B standard protocols. ALE uses anti-collision methods, multiple channels, and channel occupancy checking to avoid interference in multi-user HF spectrum. If one channel is busy, it moves to another one until it finds a good one.

Within the military environment any alternative system must be capable of interoperability across the organisation(s), and this requires agreement of technical standards. Within NATO STANAG is the NATO abbreviation for standardization agreement, which sets up processes, procedures, terms, and conditions for common military or technical procedures or equipment between the member countries of the alliance.

Each NATO state ratifies a STANAG and implements it within their own military. This provides common operational and administrative procedures and logistics, so one member nation's military may use the facilities - stores and support for instance - of another member's military. STANAGs also form the basis for technical interoperability between a wide variety of communication and information (CIS) systems essential for NATO and Allied operations.

The NATO standard STANAG 5066 is used extensively for HF military, government and commercial data communications. STANAG 5066 is a NATO specification for running data applications over HF Radio. Operating over an HF modem STANAG 5066 provides an interface for data applications to use and share an HF modem. It provides core data link services to enable applications to operate efficiently over HF radio, and specifies a protocol that enables a clean separation between applications and modem/radio level.

Over time the expectations of immediate results have already been realised by the Internet and mobile phone technology, where the press of a button brings instant information and communication without any need for operator intervention, knowledge or experience. HF radio has traditionally relied on the knowledge, experience and skills of operators to select optimum frequency, data rate and other parameters to optimise link performance. Any viable modern HF system must de-skill the operation: thus operation to the user seems fast and automatic.

This was a most interesting update on modern data comms from a military/defence perspective and, given its many complexities, was presented in an easy to understand way.

John Longhurst G3VLH

CARC MEETING March 2011

2011-07-11T09:33:00.000+01:00

An Introduction to Microwaves Part 1 by Derek Atter G3GRO

For various reasons, it was necessary to have a change of programme for the March meeting. Without a speaker we had to find a replacement at relatively short notice. As valiant as ever, Derek G3GRO stepped up to the plate. His presentation, originally scheduled for the May meeting was titled “An Introduction to Microwaves - Part 1.”

Now as many of us know, in addition to his amateur radio activities, Derek in his working life was a professional microwave engineer and he has a wealth of knowledge and experience at his fingertips built up over many years to pass on in this specialised area of communications.

The microwave spectrum is usually defined as the frequency range from 1.0 to 300 GHz, with most common applications being within the 1 to 30GHz range. The microwave spectrum is divided up into a series of sub-bands as shown in Table 1. below.

L band 1 to 2 GHz
S band 2 to 4 GHz
C band 4 to 8 GHz
X band 8 to 12 GHz
Ku band 12 to 18 GHz
K band 18 to 26.5 GHz
Ka band 26.5 to 40 GHz
Q band 30 to 50 GHz
U band 40 to 60 GHz
V band 50 to 75 GHz
E band 60 to 90 GHz
W band 75 to 110 GHz
F band 90 to 140 GHz
D band 110 to 170 GHz

Table 1. Microwave Spectrum sub-bands

As a conversion guide, a 30-centimetre wavelength is equivalent to 1 GHz (to convert from frequency to wavelength, divide the speed of light 300,000,000 meters per second by the frequency in cycles per second to get metres of wavelength).

Starting with the basic means of getting a microwave signal from A to B Derek introduced us to coaxial lines in various forms, suspended strip line (or tri-plate line), printed circuit micro-strip, waveguide and the Goubau Line. Waveguides included rectangular and circular, size adapters and coax to waveguide transitions.

Derek suggested three typical routes for the newcomer to start on microwaves -
• Wideband Gunn Oscillator/DRO
• G4WDG Modules
• Mix and Match surplus units

Klystrons are used as amplifiers at microwave frequencies to produce both low-power reference signals for superhet radar receivers and to generate high-power carrier waves for communications. The klystron is capable of amplifying or generating microwaves with greater control and precision than is available from the magnetron.

Reflex Klystron Oscillator

Early amateur 10GHz Microwave Power source. Used as Local Osc.and FM TX - approximately 10mW RF output. Originally developed in WW2 as Radar LO.

Magnetron
The “secret weapon” of WW2 this high powered vacuum tube enabled the Allies to develop high power microwave Radar and can produce up to 5 MegaWatts of Pulsed RF. In addition to radar and communications use the magnetron is used in domestic microwave ovens.

Travelling Wave Tube (TWT)
The TWT is employed to amplify radio
frequency signals to high power, usually in an electronic assembly known as a travelling-wave tube amplifier (TWTA). A common use of TWTAs is as an amplifier in satellite transponders where the input signal is very weak and the output needs to be high power.

Travelling Wave Tube (TWT)

Input RF at (2) continuously interacts with, and velocity modulates travelling electron beam, to produce much-increased RF at output (6). - Capable of very high gain up to 50dB +. (4) is attenuator to suppress backward wave. Basis of BWO oscillator

The TWT was a very popular device on Amateur microwave bands before availability of transistor PA’s. G3GRO used TWT at Masthead on 10Ghz fed with 2.4kV helix voltage.

Gunn Oscillators

The “Solfan” Gunn diode oscillator & Mixer assembly ex- Doppler intruder alarm is readily convertible to 10Ghz ham band and popular for wideband FM or ATV use. Around 10milliwats RF output

Transmission Lines are the coupling devices used for transferring a microwave signal from one part of the transmitter, amplifier or other equipment to another part of the circuit. Transmission lines come in number of forms from coaxial cable through to waveguide, depending on the application.
This was an extremely interesting presentation, and an invaluable introduction to this highly specialised area of communications. We look forward with anticipation to Part 2 of Derek’s talk later in the year.

John Longhurst G3VLH

Another 2m Contest from CARC Hut 18

2011-07-09T11:28:00.003+01:00

Following the recent success of Brain and Howard taking part in a 2m QRP contest from the CARC clubhouse, I was inspired to try my hand.

I had intended to spend the majority of the evening of Tuesday 5 July sorting out the equipment returned from Kent after the RSGB VHF NFD contest of the previous weekend. However it occurred to me that I had everything to hand to make a good stab at that evening's RSGB 2m UKAC contest. These run every Tuesday evening of the year with the first Tuesday of the month being 2m, the second 70cm, the third 23 and 13cms, the fourth Tuesday for 6m and when there is a fifth Tuesday in the month this is used for 4m.

You can find the calender here http://www.rsgbcc.org/vhf/

The rules are fairly simple with the normal 1pt per kilometer worked multiplied by the number of unique locator squares of UK contacts i.e. IO91, IO92, JO03 etc. You can of course work European stations and these do count for points (the number of km) but their locator squares are not counted towards the multiplier. This is deliberately designed to encourage UK stations to work each other and increase activity, at the same time giving stations all over the UK a fair chance at doing well.

So instead of tidying the clubhouse (don't worry I did that on Wednesday 6th), I dug out my old IC275H and the 400W 2m PA, hooked it all up to the club 17element beam and tested it out. All seemed to work OK despite not having the masthead preamp which has been repaired but is awaiting fitting to the tower. I didn't bother with a CQ caller as the contest is only 2.5 hours long, starting at 1900Z and finishing at 2130Z. This proved to be the right decision.

Unfortunately neither did I have my adapter lead with microphone preamp to allow the normal Heil HC4 headset to be used with the IC275. Most Icom radios supply 8V on the microphone pin which at a minimum need a capacitor in line to prevent damage to the Heil mic insert. This 8V is present to power a mic preamp built into Icom microphones. This means that the level of other non Icom microphones is too low and needs an additional microphone preamp.

I ended up just using the Icom fist mic that comes with the radio.

As I had little idea how well or badly the club site would work for a 2m contest I wasn't sure how many QSOs were likely. I opted to use the Minos logging software written specifically for RSGB VHF contests by Mike Goodey, G0GJV. This excellent piece of software has all the contests preloaded ensuring that they are scored correctly. Simply enter the station information such as your call, your locator etc and the software does the rest. A good tip is to ensure that your PC clock is correct. Minos uses this clock to log the QSOs.

You can find documentation and downloads here http://minos.berlios.de/

Operating as G6RC, the contest itself proved to be very enjoyable. At times it was more like HF than VHF with 3 or 4 stations replying to a QRZ call. In total I worked 131 QSOs in 2.5 hours with ODX being MM1DDD/P at 598km. Also worked were GI, EI, GW, F, DK ON and PA. I deliberately didn't spend much time with the antenna pointing at Europe but in hindsight it might have been worth a short period bagging the big stations at 700+km for extra points.

The claimed scores for the contest can be found here

http://www.rsgbcc.org/cgi-bin/claim.pl?Contest=144MHz%20UKAC&year=2011

At the time of writing, with the execpition of Bryn, G4DEZ and Dave GI4SNA both of whom have excellent VHF QTHs, equally good equipment and are seasoned operators, the other stations above G6RC are all portable, a huge advantage in a VHF contest.

So lessons learned.

The CARC clubhouse is a great site for UK VHF/UHF/SHF contests.

The IC275H is a great receiver. I barely suffered from QRM despite many other big stations on the band. It is certainly my radio of choice.

I need to be better at working pileups. Picking the full call, first time from the melee will certainly speed up the QSOs leaving time for even more.

Get the headset working properly. Bring the right lead.

Move the computer screen down making it easier to operate the logging. The radio doesn't need much tweaking and can easily sit off to the right of the computer screen.

So the next 2m UKAC contest is on Tuesday 2nd August. I hope to be at the club to give that a go. I will have had knee surgery the week before so it might not be possible. If anyone else is interested in this or other Tuesday evening events, let us know.

Alternatively if you fancy a portable entry that too can be great fun. Remember to claim the score both individually and for the Crawley ARC.

73
Mike
G0KAD

Summer Social Event Saturday-23rd July 2011

2011-07-05T09:44:00.000+01:00

FOLLOWING recent the Successful Club Dinner Held in May,

The Hon. President and the CARC Committee Extend an

Invitation to Members, XYLs/Yls and Family Members

to join them in a new Venture :

“The President’s Lunchtime Garden Party”

To be Held at the QTH of the Hon. President, Derek Atter, G3GRO at No.1 Little Crabtree, West Green, (Off Ifield Avenue ) 12-00 for 12-30 until approx 4-00 pm

A Substantial, Mainly Cold Buffet Lunch will be served including
with it a Glass of Wine and Soft Drinks etc. plus afternoon tea later.

Proposed Menu :

Assorted Sandwiches :
Brown & White Bread With the following fillings :
Cheese & Home-made Chutney, Ham & Tomato,
Egg & Cress Mayonaise, Coronation Chicken.

Crudités :
Batons of Carrots, Cucumber, Celery, Peppers,Spring Onion,
Cherry Tomatoes, Tiny Pickled Onions.
Bread Sticks, Assorted Crispsands Savoury Biscuits

Dips :
1000 Island, Mild Curry chilli & Philadelphia Cheese
4-Cheese dip, Honey & Mustard

Hot Items :
Sausage Rolls, Barbecued Chicken Legs, Cocktail Sausages on Sticks
Mini Meatballs on sticks, Chicken, Bacon & Mushroom Vol-au-Vents

Deserts:
Old Fashioned Sherry Trifle; Chocolate, Strawberry & Cream Gateau

Cost per Head : £8-00
Bring a bottle if you fancy more than one glass of wine (If you are not driving !!)

It is planned that the event should take place in the garden but if we happen to
be unlucky with the weather, we plan to transfer inside to the conservatory and
sitting room etc. - even, God forbid, to the shack !!!
( Note, Parking on Little Crabtree is restricted until 5-00pm on Saturdays but some parking
spaces will be available. - Collect a resident parking permit immediately on arrival at
No.1Little Crabtree and place on the dashboard. Alternatively free parking is available
directly across on the opposite side of Ifield Aveue 100 yards away in the car park by the
Horticulture Club and Labour Party Club )

To reserve places for the lunch, please contact Richard, G4ANN, the Hon. Treasurer
ASAP at the Club or telephone on 01342 715333 or via e-mail : G4ANN,
g4ann@copthorne.org.uk so we can quickly establish numbers.

Our First 2m Contest

2011-06-15T22:16:00.000+01:00

Recently we were made aware of the Practical Wireless 2 Metre QRP Contest taking place on the 12th June. Power is limited to 3 watts and you can operate /P or from a home/club station. It started at 0900hrs to 1600hrs UTC. Two of us, Howard G4PFW and myself decided to have a go. We tested my FT290 but it was not performing too well with the Clubs antenna system but the FT817 was fine, it performed all day without a hitch. A borrowed power supply (thanks Ted) and a few of my adaptors and we were ready to go on time.

We started, using the callsign G6RC and sweeping the frequencies to see who we could hear then tried to make contact to build up the score, later we sat on a frequency and tried many CQ calls without much success. At the time the weather in the South of England was terrible with a low pressure system and heavy rain coming up from France, I am certain this suppressed the signals and made hearing other stations elsewhere difficult. We had most of the early contacts with stations in our own grid square apart from one in France (JO00UV) and one in Belgium (JO10UV). (Where did they come from?) Later we started to get one or two out of our area then it all went quiet as lunchtime approached. As the contest was not a high pressure one we decided to take a break but still listen where we could.

As it was a Sunday our normal club meeting took place and many members were very supportive of our efforts. (You know who you are)

Howard at the helm

The afternoon continued much as before with sporadic contacts being made. We were surprised when others were giving numbers like 072 when we were still in the lower 20’s. How were they doing it, maybe they were outside the weather depression or on higher ground and were reaching parts that others could not. Not to be put off we continued and were rewarded when I made a contact in the Belfast area. The last hour or so we worked harder and although we could hear a few more, we were unable to pull them out of the hash.

Our total for the day was 25 contacts spread over 9 locator squares, not a lot considering the work done. Conditions were very difficult. A steep learning curve to us newcomers to 2 metre contests. This would be an ideal starting point for those newcomers to the hobby. We now have to wait for the results to be published.

Our thanks go to all the members that supported our efforts and to the club for the use of the shack on the day.

BrianG
2E0MZB

G3NZP - SOS Champion

2011-06-14T18:29:00.002+01:00

The following announcment has just appeared in the latest RNLI 2011 SOS Radio Week Newsletter:

"Icom individual award

The individual that raised the most money (over £240) for the Royal National Lifeboat Institution (RNLI) during SOS Radio Week 2011 was Malcolm Harman (G3NZP) and for his massive contribution he receives an Icom IC-E80D D-star dual band hand-held transceiver".

Malcolm would like to thank all those members who sponsored him and made a donation. It seems a very nice little radio (and most appropriate considering Malcolm's contribution to GB7MH) and he says that without CARC help he would not have won. Club members that still have a copy of March 2011 RadCom can be reminded about the event.

Malcolm says that Icom wish to present this prize at a suitable venue (rally, club meeting, etc.) and have photographs taken to issue in press release. We look forward to seeing this.

Congratulations to Malcolm, and on behalf of Malcolm and the RNLI, thanks to all who sponsored him

Stewart/G3YSX

A Double Whammy for Biton and an Intermediate Call for Graham

2011-05-24T14:03:00.004+01:00

Last week CARC members Graham Parsons (2E0XDZ) and Biton Walstra (2E0WAO) both obtained their Intermediate Licences. Each had self studied for some time before taking the examination on the same Saturday afternoon. However in Biton’s case he had to pass the Foundation first, so success at two levels within a few hours. Congratulations to both candidates and once again thanks to Dick Lupton for invigilating.

Of course all necessary practical assessments had to be undertaken prior to sitting their exams and this was accomplished some weeks earlier during an all day session in Hut 18. I think both students enjoyed the day and learnt a lot, especially while calibrating an analogue VFO, one of the more interesting required elements, particularly in these days of synthesised radios. None of this would have been possible without the able assistance of fellow trainer Ted MacDonald.

Malcolm Harman (G3NZP)
Training Secretary

T&K Brackets

2011-05-08T21:31:00.004+01:00

Over the last couple of weeks there has been an interesting discussion on rsgbtech@yahoogroups.com (http://groups.yahoo.com/group/rsgbtech/) on the subject of T&K brackets. The simple question that started the thread was which way round to the two brackets go?

Although one normally sees T&K brackets mounted with K at the bottom, I pointed out that there was some useful information here: http://www.aerialsandtv.com/polesandbrackets.html#PictureOf12&24T&Ks , which says :
There are two opposing views as to which should go at the top. The K is obviously the more robust bracket and the received wisdom is that this should go at the bottom because, being further down, the wall is stronger there. However the top bracket is probably under the most stress (certainly if the wind is blowing the pole away from the wall) and so some think the K should go there instead ! Basically one has to work out the relative importance of the two factors for the particular install being undertaken. For an install at the peak of a gable I would put the K at the bottom, whereas on a strong flat top wall I`d put the K at the top. Basically it`s six of one, and half a dozen of the other, but,if in doubt put the K at the bottom

More information can also be found at http://www.wrightsaerials.tv/

Sound reasoning for the K at the bottom model was provided by Graham G8EWT who said:

The reasoning was that, as has already been stated in this thread, it is the stronger of the two and is better able to carry the vertical load. Hence the U bolt needs to be tightened really well. A tightened bolt reduces the chances of the pole rotating or sliding down but risks deforming the circular shape of the pole and therefore reduces its ability to withstand sideways forces without buckling. As the K is carrying the vertical load the function of the T is simply to provide resistance to lateral forces. It only needs to be moderately tightened and thus the risk of deformation is eliminated.

At this point in the debate I remembered a note on the subject written in March 1984 by Pat Hawker drawing attention to BS6330: Code of practice for reception of sound and television broadcast, which has some useful information on the subject. However I had long since lost track of my copy of the text.

Ian GM3SEK noted:

It would be worth tracking down, because that guide was written for Band 1, 2 and 3 aerials which were very similar to yagis for the VHF and UHF amateur bands. That isn't so true of modern broadcast aerials. One tip that you won't see in a British Standard is to insert a length of wood where the tube passes through the top bracket, which is the point of highest bending stress. The wooden filler prevents the thin-walled tube from collapsing, and spreads the bending stress away from the U-bolt. For the typical 50mm/2in tube, use a 600mm/2ft length of 37mm/1.5in square timber with the corners shaved off to make a rough octagon shape. Almost any kind of straight-grained timber will add a lot of strength. Do not aim for a tight fit - make it just firm enough to hold in place when you install the mast, and after a few days outdoors it will swell to a tight fit. (The octagon shape is actually better than a turned cylinder because it leaves room for the wood to adjust as it swells - and very importantly, it leaves gaps for water to drain past.)

Unfortunately BS6330 is no longer available, searched my study and tracked down my copy of BS6330 in box of papers, unopened since we moved house 8 years ago. I found quite a few other "treasures" on the way.

It does not have quite as much information as I remembered, but does give some information on types of loading (in terms of antenna type) mast length and dia, spacing of fixing etc. There is a lot of information on distribution systems which is not relevant to the subject in hand.

As to TK, although it always shows T over K in the drawings, all it simply says "where double brackets are used for all mounting one should be a tripod in order to provide proper support
against vertical thrust. The brackets should be spaced at least 450mm apart.

Since most of the text in BS6330 is not applicable to our interests. The key part, which contains valuable information relavent to the type of small to medium sized VHF and UHF amateur radio antennas has been posted here: http://carc.org.uk/carc_ftp/Extract%20from%20BS6330.pdf.

- Stewart/G3YSX

HF conditions Improving

2011-05-07T08:16:00.002+01:00

G3GRO Reports:

HF conditions continue to improve on 7Mhz and 14 Mhz - especially on 7Mhz. - Have been hearing US & VE stations at good strength late in the evening evening on 40m

On Wednesday night (4th May) just after midnight local time, I worked "Doc" VO1DSK in Newfoundland at good "chat" strength on 7152kHz SSB. is signal was 5&8-9, and he gave me a report of 5&9 +10dB !! He was in QSO with John, KC3FL in Florida who was 5&7.and who also gave me 5&9.

The antenna in use was my 139ft 80m multi-band offset dipole (or windom) the feed point of which is up at about 35ft.agl. It is a full-wavelength long on 40m running roughly north-south with one third of its length from the feed point sloping down towards the north at about 45 degrees, and has 4 lobes in the horizontal plane, one of which points NW putting a good signal into USA/Canada.

I was using my FT1000MP transceiver and Expert 1K-FA linear with 400W to the antenna.

Last night, (Thursday 5th May ) just before midnight (local time) I was again hearing hearing USA stations at good strength with KE1Y and W2VP working into a SSB net. but then tuned down to the CW end of the band and heard PZ5RA in Surinam, South America on 7007kHz calling CQ with no pile-up on him! I called him and we exchanged 599 reports.

73, de Derek, G3GRO.

Alan's Lab

2011-04-28T09:28:00.002+01:00

Looking up the followup information on the electrometer took me to the really cool electronics experimentation site of Alan VK2ZAY at http://www.vk2zay.net/

It's well worth a visit.