National Field Day with the Sussex Downs Contest Group
GB1SCW Shoreham Coast Watch Special Event Station
Jonathan G1EXG’s Short Circuit No. 4 Monitoring the Manfred Memorial Moon Mission Club Diary & Rallies in October
September - October
Worthing & District Amateur Radio Club Established 1948 Website: www.wadarc.org.uk
E-mail: info@wadarc.org.uk Life Vice President: Peter Robinson G8MSQ WADARC meets every Wednesday at 8pm in the Lancing Parish Hall, South Street, Lancing BN15 8AJ. All who have an interest in radio communications and associate subjects, whether a licensed amateur or not, are invited. WADARC can also arrange training for the radio amateur Foundation, Intermediate and Advanced licences. The WADARC Committee 2013 - 2014 Phil G4UDU Andy M6RFE Dawn 2E0ESK Jonathan G1EXG Peter G4LKW Norman 2E0RKO Andrew G1VUP Andrew 2E0TCB Peter 2E0FVL
Chairman Secretary Treasurer Ordinary Member Ordinary Member Ordinary Member Ordinary Member Ordinary Member Ordinary Member
WADARC Ex Officio 2013 - 2014 Membership Manager Contest Manager Ragchew Editor Website Training Officer
Peter Graham Roger Andrew Andrew
2E0FV G4FNL G4TNT G1VUP G1VUP
WADARC Club Nets (all times are local) 07.30
Sunday
3.725MHz ± QRM SSB
19.30
Monday
145.425MHz (V34/S17)
11.00
Thursday 7.106MHz ± QRM SSB
CONTENTS From the Editor’s Keyboard ...................................... 4
Presidential Ponderings ........................................... 5
National Field Day 2014 ........................................... 6
Manfred Memorial Moon Mission .............................. 15 G1EXG’s Short Circuits ............................................ 16
Special Event Station GB1SCW ................................ 18
Club Diary ................................................................. 20
Rallies in October ..................................................... 21
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FROM THE EDITOR’S KEYBOARD
W
elcome to the latest (if somewhat belated) edition of Ragchew. I had hoped to get this issue out some weeks ago but I’ve had to wait for some contributions. Some still have not arrived but, luckily, I’ve been able to fill this issue because I already had on file an excellent article written by Graham G4FNL that I held over from last time. It’s a nicely detailed account of the National Field Day event that he took part in as part of the Sussex Downs Contest Group. Phil Godbold G4UDU sent in a snippet about the Manfred Memorial Moon
Mission that should be of interest to anyone who wants to try receiving a signal from space. The spacecraft will stage a lunar flyby on October 28th and it might be possible to pick up its signals here in Worthing. If you do manage to receive it, you stand the chance of winning a prize! Jonathan Hare G1EXG has kindly supplied the fourth in his series of short circuits. This one is a brief explanation of how diodes work along with an interesting list of the various types that are available. Courtesy of Pete 2E0FVL and Howard M0HJF, we also have an account of the Shoreham Coast Watch special event station GB1SCW that operated from the NCI lookout station at Shoreham Beach last month. There’s no Member’s Profile in this issue because no one has submitted one. The feedback I’ve received from readers about the two that have appeared so far is that they liked them and they would like to read more. So would I but I can only print what you send in so please, if you’d like to follow Ted G3EUE and Pete 2E0FVL and let fellow members know more about you and how you came into the hobby, do get in touch. Similarly, if you have any comments on the content or look of Ragchew, please let me know. My e-mail address is roger@radiouser.co.uk and if you’re reading this on your computer, you should be able to click on the address to open your e-mail program automatically. 73, Roger G4TNT
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CHAIRMAN’S CHATTER
T
his summer has been a busy time for the club with many events taking place. We have set up special event stations at the Fire Station in Worthing, Shoreham Lighthouse and for the Coast Watch event plus we took part in the SSB field day. You’ll be able to read about these in Ragchew as the reports and pictures come in. One of the most significant events for the club this year was the sudden loss of John G8FMJ, the club's president. Because he was involved with so many aspects of the WADARC, there have been many tasks we’ve had to fill. Apart from the work he did for the club, John was also very active on the air, both on the regular club nets and when indulging his passion for contesting. With Chris G3NDJ and now John no longer with us, we need the membership to make use of their own radio licenses and maintain an active presence on all of the bands. We have three regular weekly schedules on 80, 40 and 2m but it’s usually the same small group of people who take part in them every week. I would like to hear more of the membership being ‘Active Radio Amateurs’. If there is a problem with your antennas or radio equipment, please remember there is a wealth of knowledge within the club – just ask. In addition, the club has a selection of radio equipment that is for use by the membership to get you on the air. Finally, the AGM is now almost here (it’s on Wednesday October 8th) so it’s time for us to select the club’s officers and committee for the coming year. The following week’s meeting will be a round table discussion evening to find out what members want from the club with respect to meetings, speakers, outside events and so on. Please do come along and let us hear your views so that we can then put together a plan for the coming year. 73, Phil G4UDU
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NATIONAL FIELD DAY 2014 National Field Day with the Sussex Downs Contest Group Graham Bubloz G4FNL
G4FNL/P 2014 operators – Kevin VK6LW, Graham G4FNL, Alan G3XAQ and Peter G4BVH
M
y friend Peter G4BVH and I reckon that together we have continuously taken part in National Field Day (NFD) – an annual CW contest on all HF bands over a 24 hour period – since 1981. We have named our group the Sussex Downs Contest Group. For many years, we retained the same formula – with occasional but minimal improvements – essentially, doing more of the same each year. However, in around
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2005, my interest in radio was rejuvenated, mainly because I had more time available to devote to the hobby. Since then, I have been keen to put effort into improving at least one significant aspect of NFD operation each year. In 2013, the rules went through a major shake-up and since then, to operate effectively within the Restricted section of the contest, you need to be able to erect multiple wire antennas and make the best use of the 22m total mastage allowance. The limit for the total wire length for all antennas is 120m.
Changes For approximately 20 years we used Lording’s Farm, the same QTH as the Worthing and District ARC uses for SSB Field Day but for the past six years, we have moved to a new location on top of the South Downs. The thinking was that whilst we had done reasonably well from the farm, we never did really manage to crack the top three placements. Moving QTH was a leap into the unknown but one that certainly seems to have paid off. Over the intervening years, we’ve have tried many different radio and antenna configurations but once the rules changed as mentioned above, we decided to completely redesign the antennas. Nagging away was also a realisation that with just two of us, it was really a bit too ambitious and we realised that it would be far better with another CW operator. For a couple of years during this period we were joined by fellow WADARC member Danny M0GMT but he was unable to continue for a variety of reasons. So, when Alan G3XAQ, who lives near Canterbury, approached me at the RSGB Convention in 2010 and asked if he could join our ‘duo’ team, we gratefully accepted his offer and since then we have operated with a permanent three man team, which certainly makes the setting up and gathering of equipment that much easier. The good news for us was that for 2014 we knew that Kevin VK6LW was going to be visiting the local area and had already agreed to come along for the whole weekend. Having four decent CW operators was clearly going to be a significant bonus for us. Following on the trend of trying to improve year-on-year, we decided that for 2014, we would also have two decent HF CW radios running, as in 2013, but this time we would use two Elecraft K3 radios because they have better receivers (and substantially less phase noise distortion) than our existing Yaesu FT1000MPs.
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This would require a different lock-out system (to prevent the two radios ever transmitting simultaneously) but we could reuse a diplexer along with transmit band pass filters plus a six-pack (auto antenna selection unit) that we’d made for the 2013 event to ensure that we could operate on any band with either radio. In addition, to keep the log synchronised we would need to have two laptop PCs that were fully networked. Finally, we were also allowed to use our own skimmer (to populate the band map on the logging PCs) to keep an eye open for stations that we hadn’t already worked and to keep a beady eye on openings on 10 and 160m, where each QSO is worth double points. Anyway, enough of the history, but it’s fairly safe to say that what we had planned was quite complex, and there were many things that could go wrong…
Planning As the event is annual, there is little that one can do if anything does fail except have as much duplication planned for each piece of equipment as possible. With that in mind, we had spare PCs and radios but our Achilles heel was that we only had one generator. Perhaps for future years, we should take a spare. We did have a dry run through earlier in the year in April just to make sure our antennas were resonant and to simulate the environment as much as possible. The photo shows the test setup.
The test setup at the local University site to trial the new antennas.
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New for 2014 was a different operating shack. For many years, we’d used my caravan but I’d sold that earlier in the year and we all agreed that we would not even contemplate using a tent so instead we hired a Ford Transit van, which proved to be a worthwhile exercise.
Our operating shack.
Setting Up We arrived on site on Saturday 7th June at 09.00. The weather was very wet and windy but the forecast was better for later on. We waited for an hour or so hoping that we could avoid getting absolutely soaked but as the clock was ticking, we decided that we would have to brave the rain and get cracking.
As you can see, the grass was very long and we did get wet through wading through this stuff. However, by approximately 13.00, we had managed to get the two support masts up and our five wire antennas aloft. By then, the sun had begun to shine, which was very welcome, and we managed a quick bite to eat.
G3XAQ and G4FNL setting up mast number 1.
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Alan, Kevin and I were allotted the task of erecting the masts and antennas while Peter was left to organise setting up the radios and associated IT equipment. Needless to say, there were some unexpected problems. Despite the dry run through beforehand, it turned out that the lock-out box was badly affected by RF. It had been tested A makeshift clothes/shoes drier. and had plenty of decoupling installed but nonetheless, it wouldn’t operate correctly in the real life situation so Plan B was instigated and a manual version of the auto lock-out unit was quickly devised and installed. That delay had a major impact on our readiness and we were getting dangerously close to the start time of 16.00. The final piece of equipment that we needed to install was the Software Defined Radio (SDR). I am very grateful to fellow WADARC member Vic G8MUQ for the loan of his Perseus SDR, without which we would have fared far worse. The SDR was connected via a long (300m) length of coax to our SDR antenna, which was a Datong Active Antenna. This device is fantastic. It’s a simple, short (2m?) wire dipole that I strung up vertically (for omnidirectional properties) along a bamboo cane. The antenna has a small wideband preamplifier that boosts the signals sufficiently for the SDR to be able to resolve some weak signals. Unfortunately, it also amplifies any local RF signals such as our own transmit signals but we managed to avoid any overloading of the front end. The receiver was then connected to another laptop PC devoted to running the Skimmer software, which in turn was used to populate the band maps of the logging programme. We posted our operating plan (a roster) on the inside wall of the van and we also had a separate sheet showing our previous scores from last year’s contest to give us a guide as to how well we were doing during this year’s event. With five minutes to spare, we had managed to get all the radio gear set up and working. Phew!
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Masts and antennas – with the English Channel in the background.
Kevin VK6LW and Peter G4BVH in a lighter moment.
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Operating The HF conditions seemed very good so we started immediately by looking on 10m. We managed 63 QSOs in the first hour, which was 13 up on the previous year but, more importantly, it showed 10m was open, which was good for us as all QSOs there are worth double the points of other HF bands. From the photos, you will notice that we have two operators, each able to tune and operate on their own separate band unless one of them has a ‘run’ going, in which case there is little else for the other operator to do. In fact, rather than ‘running’, we spent more time in search and pounce (S&P) mode. Unfortunately, an inadvertent byproduct of this may have been that it was more difficult to find us on the bands. You will also see that whilst we had CW paddles, the main exchanges and sending is all done from the keyboard, using macros. We operated for roughly two hours on and two hours off.
Alan G3XAQ and Kevin VK6LW
In order to understand whether you had the ‘right’ to transmit, each operator had to keep an eye on a large red LED indicator that dictates who has priority, selected on a first come, first served basis. As soon as the operator releases his footswitch, then it’s back to whoever is first to press the footswitch to get priority again. It can be very frustrating at times. Clearly, the altruistic aim was to maximise the score – and we all understood these rules – but it was still frustrating!
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As the day progressed, we started to realise that we had a reasonable signal and we were able to work most stations that we could hear. In addition, because the propagation favoured the south, we seemed to be able to work into Europe on HF, which is normally quite challenging to do (often we heard stations in GM working strings of DL portable stations but we Antennas and masts at 04:22 BST – around sunrise. could do nothing at all). We also began to realise that many of our close rivals did not seem to be getting the same propagation that we were enjoying. Anyway, by 2000z, five hours into the contest, we were on serial number 362, which was 100 above the same time last year. Things were looking good. By 0300, we maintained this lead over last year and we had a feeling that we seemed to be doing better than many of our peers. We spent a good amount of time on 160m. Like 10m, this band scores double points so it’s worth searching and squeezing the band dry. Unfortunately, by our own comparisons, we ended up with a low QSO total for 160m. In the past, we can recall working 180 or more stations on top band. This year, we had just 122. However, it seems that QSO totals on 160m were down for all competitors.
Kevin VK6LW and Peter G4BVH
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It’s not all serious…
Graham G4FNL and Peter G4BVH
Results After 24 hours operating and towards the end, we were fairly sure that we had done enough to do better than our rivals. However, as I write this, we still do not have the adjudicated results but going just by claimed scores, we appear to be in first place in the Restricted section. If we have won, it will be the first time we’ve achieved this since we started back in 1981! Here are the final claimed QSO and Points numbers for us this year. Band 1.8 3.5 7 14 21 28 Totals
QSOs 122 161 236 378 236 214 1347
Points 846 584 790 1138 717 1256 5331
We take part in this particular competition for a variety of reasons. Here are a couple:
it’s fun and we learn a lot each time; we compete against our peers, which is always a challenge and because of this, there is a huge reward when things go to plan.
This was certainly our experience in 2014. We’ll be back again in 2015 to see if we can improve some more… 73, Graham G4FNL
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MANFRED MEMORIAL MOON MISSION
I
f you’d like to try to monitor a lunar spacecraft, you’ll have a chance at the end of October 2014 when the Manfred Memorial Moon Mission stages a lunar flyby followed by a return to Earth. The intended mission duration is 196 hours (8.17 days) and the anticipated lunar flyby will take place on October 28th 2014 at 00:28:00.000 UTC when the spacecraft will be 373,000 kilometres from the Earth and 13,000 kilometres above the Moon’s surface. Transmissions The spacecraft will transmit on 145.980MHz ± 2.9kHz and continuous transmissions will start 4,670 seconds (77.8 minutes) after launch. There will be five successive one-minute sequences sent during the five-minute cycle. The transmissions will use the JT65B digital mode and this can be decoded with the free WJST software. For those who just want to hear the signals and don’t want to decode the messages, there will also be ‘human readable’ tone transmissions. The transmitter will output a nominal 1.5W into a quarter-wave antenna. Obviously, the bigger your antenna the better but if you’ve ever tried listening to the International Space Station, you’ll know that there’s a good chance you will be able to hear it with a simple collinear. Prizes The mission organisers are encouraging radio amateurs around the world to try to receive the transmissions and send in data. There will be a number of Experiments and Contests with prizes to the winners in each category. Website For detailed information on the mission, take a look at their website: http://moon.luxspace.lu/the-mission
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G1EXG’S SHORT CIRCUITS
J
onathan Hare G1EXG continues his series of short circuits with a brief explanation of how diodes work and the various types that are available
Short Circuit No. 4: Diodes and the Voltage Rectifier
A diode is an electronic component having two wires or electrical connections. It only conducts electricity if the voltage is correctly applied (called ‘forward biased’). The diode in the circuit will convert the positive voltages of the alternating voltage or current (AC) into a series of positive DC pulses – this is called half wave rectification (we will cover full wave rectification next time). The capacitor smoothes the pulses to create a DC voltage but the quality of smoothing will depend on how much current is being drawn by the load.
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PAGE 2 There are many different types of diode, from tiny small signal devices just a few millimetres long to high current stud mounting devices the size of your fist. Different Types Small signal germanium diodes (such as OA91or AA119) are used as radio detectors in simple crystal set radios. A crystal of naturally occurring galena can also be used as a radio detector diode. Silicon diodes (such as 1N4001, 1N4002 and so on) can be used in low voltage power supplies. Varicap diodes (for example, BB111) are used in reverse mode (so they don’t conduct) but as you increase the voltage, their internal capacitance changes. You can use varicaps as voltage controlled capacitors in tuned circuits. Zener diodes are also used in reverse mode. As the reverse voltage increases, they start to conduct at a certain very precise voltage. This effect can be used to create very stable voltage references and regulators. Light emitting diodes (LEDs, see short circuit No. 1) produce light when current flows through them. Tunnel diodes initially conduct like normal diodes but then, unusually, the current actually drops with increasing voltage (a sort of negative resistance). This effect can be used to make microwave oscillators and very fast pulse circuits.
For more information see: http://www.creative-science.org.uk
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SHOREHAM COAST WATCH Special Event Station GB1SCW
T
he second year for the Shoreham Coast Watch special event station GB1SCW took place at the NCI lookout station at Shoreham Beach on September 13th/14th 2014. The club’s Windom antenna was set up along the sea wall in a north to south direction with the apex 40 foot high on the pneumatic pump-up mast.
Working primarily on the 40m band at 100W, the event resulted in a total of 239 QSLs even though band conditions for both days were challenging with both QSB and QRM. Using a trapped dipole, a small number of those QSLs were made on 2m and 70cm. Countries worked other than the UK included going foreign to the IOW, Switzerland, The Netherlands, France, Denmark, Germany and Belgium. Of special note were watch keepers of the NCI who asked for QSL cards, working from their home QTHs in Felixstowe, Helston and Ryde.
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The event increased awareness of WADARC and the work of the National Coast Watch so our thanks go to all those members who attended the station. Amongst those there were Brian G0SIU, Andy M6RFE, Ray M6IKO, Alan G4GNX, Sandra G0KAG and Norman 2E0RKO. Our special thanks must go to Andrew G1VUP for setting up the Wi-Fi and the computer logging and to Pete 2E0FVL and Pete G4LKW (both pictured) for setting up and for taking on the lion’s share of the operating. WADARC members and NCI watch keepers all said that they had an enjoyable and informative time. We hope to see you there next year, when we might broaden the scope of our special event callsign to include all waterside lookouts. The latest good news for the NCI is that in October 2014, the Marine Coastguard Agency has allocated them the marine VHF channel 65, which is another step forward in improving their communications. 73, Pete 2EØFVL and Howard MØHJF
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CLUB DIARY OCTOBER 5th .......................... Monthly breakfast meeting at the Rainbow Café 8th .......................... 2014 AGM 8th .......................... 80m CC Sprint CW Contest 15th ........................ Discussion Evening (planning next year’s events) 22nd .............................Construction Contest 23rd ........................ 80m CC Sprint SSB Contest 30th ........................ GX3WOR On-The-Air evening 1 ............................. NOVEMBER .......... 2nd ......................... Monthly breakfast meeting at the Rainbow Café 12th ........................ 80m CC Sprint SSB Contest 12th ........................ Discussion Evening 19th ........................ Talk by Graham M3ZGS of bhi – New Advancements in Noise Cancellation 26th ........................ GX3WOR On-The-Air evening 27th ........................ 80m CC Sprint CW Contest
DECEMBER........... 3rd .......................... Discussion Evening 7th .......................... Monthly breakfast meeting at the Rainbow Café 10th ........................ What is it? Quiz hosted by Peter G8MSQ 17th ........................ WADARC Christmas Evening at the British Legion Club Lancing 31st ........................ No Meeting – Hall Closed
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RALLIES OCTOBER 5th – Blackwood & District ARS Rally Rougemont School, Llantarnum Hall, Malpas Road, Newport NP20 6QB 5th – North Wakefield Club Winter Rally New Venue: Middleton Active Centre, Middleton Ring Road LS10 4AX 10th-12th – RSGB Convention The full programme of lectures available on the website www.rsgbevents.org 12th – Hornsea Amateur Radio Club Rally Floral Hall, 7 The Esplanade, Hornsea, East Yorkshire HU18 1NQ 18th – Carrickfergus Amateur Radio Group Radio Rally Downshire Community School, Carrickfergus BT38 7DA 19th – Chippenham & DARC Mini Indoor Radio Rally Neston Village Hall, Pool Green, Neston, Corsham, Wiltshire SN13 9SN 19th – Galashiels & District ARS Radio Rally The Volunteer Hall, St Johns Street, Galashiels, Scottish Borders TD1 3JX 19th – Holsworthy Amateur Radio Rally Holsworthy Community College, Victoria Hill, Holsworthy EX22 6JD 25th – Fog On The Tyne Rally Whitehall Road Methodist Church Hall, Bensham, Gateshead NE8 4LH 25th – Poole Radio Society Table Sale Old Chapel Hall, Cabot Lane, Creekmoor, Poole, Dorset BH17 7BX 25th – G-QRP Club Mini Convention Rishworth School, Rishworth, on the A672 (Ripponden) road, junction 22 on the M62 26th – The 24th Great Northern Hamfest Barnsley Premier Leisure Complex, Queens Road, Barnsley S71 1AN 26th – North Wales Rally Abergele Leisure Centre, Faenol Avenue, Abergele, Conwy LL22 7HT
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John Slater G8FMJ 1948 – 2014 22