SPECIAL EVENT STATION GB8SL AT SHOREHAM LIGHTHOUSE FOR ILLW
NEW VENUE FOR WADARC AT TS VANGUARD
Plus JONATHAN G1EXG’S SHORT CIRCUIT PRESIDENTIAL PONDERINGS CHAIRMAN’S CHATTER RALLIES
Winter 2018/19
Worthing & District Amateur Radio Club Established 1948 Website: www.wadarc.org.uk
E-mail: info@wadarc.org.uk President: Chris Smith G3UFS WADARC meets every Tuesday at 20.00 in TS Vanguard, 9a Broadwater Road, Worthing BN14 8AD. All who have an interest in radio communications and associate subjects, whether a licensed amateur or not, are welcome. WADARC can also arrange training courses for the radio amateur Foundation, Intermediate and Advanced licences.
The WADARC Committee 2017 – 2018 Chairman Alan Baker G4GNX Vice-Chairman Leslie Sampson G3JSU Secretary Andy Braeman M6RFE Treasurer Roger Ferrand G7VBR Raymond Ellett M6IKO Norman Jacobs 2E0RKO Ian MacDonald M0IAD Alex Slee 2E0UMD These Committee and Members have volunteered to accept the following responsibilities: Membership Manager Ian MacDonald M0IAD Ragchew Editor Roger Hall G4TNT Website Andrew Cheeseman G1VUP / Alastair Weller M0OAL Special Events Stations Peter Head G4LKW Online Content Coordinator Alan Baker G4GNX Outside Events Coordinator, Facilities and Bookings Norman Jacobs 2E0RKO Training Coordinators Alastair Weller M0OAL / Andrew Cheeseman G1VUP Exam Secretary Alastair Weller M0OAL Press and Publicity Coordinator Les Sampson G3JSU Quartermasters Andy Braeman M6RFE / Raymond Ellett M6IKO Club Calendar Coordinator Alex Slee 2E0UMD Weekly News Email Phil Godbold G4UDU, Alan Baker G4GNX, Jonathan Hare G1EXG
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
Editorial .................................................. 4 Presidential Ponderings ......................... 7 Chairman’s Chatter ................................ 9 GB8SL by Edmund M0MNG ............................. 11 Short Circuits by Jonathan G1EXG .................... 17 Rallies ..................................................... 20
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EDITORIAL
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elcome to the Winter 2018/19 edition of Ragchew. The main news this time is that our Club is on the move again. After many happy years in Lancing Parish Hall, the Council told us it was going to rent out our room to a nursery that would need the full-time use of it and we were asked to move into another room. We did but it didn’t work out well so we decided to move just across South Street to the Lions Hall in Roberts Road. It’s a nice hall and everything was fine there for a while but it soon became obvious that parking was a problem. There is a public car park a few minutes’ walk away but those few minutes can seem like a long time on cold, wet winter evenings so most members chose to park in Roberts Road and its offshoots instead. Like most such small side roads, there aren’t many spare spaces and when we took some of them for a couple of hours once a week, the local residents weren’t happy. There were even instances of them putting out cones to block off sections of the kerbside. At the same time, the number of members attending Club meetings started to fall and most of us believe that difficulties with parking might be at least a part of the reason for this. New Venue Luckily, we have now found a new venue for our meetings and it looks as though it could be our best one yet. It’s the Sea Cadets Headquarters at TS Vanguard, 9a Broadwater Road, Worthing and one of its attractions is that it has its own onsite parking (for about 10 cars) and there’s plenty of on-street parking nearby as well. It’s also near to train stations and on a bus route for those who don’t drive. However, there’s much more to the decision to move there than improved parking. The building has plenty of room,
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C far more than we need, and we will have exclusive use of it on our meeting nights. There are some large classrooms rooms that we can meet in and if we ever need more space, we can use the larger main drill hall. It also has a galley and storage for our tea stuff. We’ll also be able to use the building for training classes, either on our meeting evening or on occasional weekends. Probably the best part is that it has a separate radio room! It’s lockable and we will be able to install our own equipment in it. Not only that, the building already has VHF and HF antennas in place! They’ll probably need some attention and we’re going have to spend some time setting up a shack but it’ll be worth it because we’ll end up with a meeting place with its own radio room and antennas almost in the middle of Worthing. Meeting Evening Unfortunately, our usual meeting evening (Wednesday) is not available, nor are Thursday or Friday so the only evenings we had to choose from were Monday or Tuesday. At a recent regular Club meeting when those two options were put to the members present, the overwhelming preference was for the Tuesday – only one member voted for the Monday. Similarly, the Club then ran an online poll to let the entire membership have a say in which evening and once again of those members who voted, only one wanted it to be Monday. All the rest chose Tuesday. Therefore, the next Club meeting will be on Tuesday January 15th at 20.00 at TS Vanguard, 9a Broadwater Road, Worthing BN14 8AD and then weekly on Tuesday evenings thereafter. Getting There TS Vanguard is located on the A24 Broadwater Road. It’s on the lefthand side as you’re coming out of Worthing and it’s worth noting that you can’t turn right into if you’re on the other side of the road heading towards Worthing. It’s just past the Langton Road side turning and the photo on page 4 shows the entrance so you should be able to spot it easily. If you find yourself driving along the A24 with Worthing Motors and a parade of
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C small shops and eating places on your right, you’ve gone too far and missed it. Everyone who’s been there has said it could be the ideal new home for WADARC so please do come along and see it for yourself. In This Issue In his Presidential Ponderings column Chris G3UFS reflects on his recent car woes and passes on a joke while in his Chairman’s Chatter, Alan G4GNX comments on the new venue, the Club’s forthcoming 70th special event station and also asks for your help. Jonathan G1EXG’s Short Circuit column this time is devoted to varicap diodes, that is, diodes that act as variable capacitors. He explains how they work, what they do and how they are used. Edmund M0MNG kindly sent in an article about his favourite outdoor event, GB8SL, WADARC’s special event station for the International Lighthouse and Lightship Weekend. It sounds as though he had fun.
Ragchew In the last issue I asked how members want Ragchew to be delivered (online page-turning, online PDF, emailed PDF and so on) and then I wondered about the relevance of Ragchew now we have the reflector, a website, a weekly newsletter, a Facebook page and videos on YouTube. I then took that thought a stage further and asked if we should keep publishing Ragchew and I asked for your comments on whether there is now a case for scrapping it and beefing up the weekly newsletter, the website and the Facebook page instead. I think the response I received says a lot – just two people wrote in to comment! Is that an indication of just how few members read Ragchew nowadays? What do you think? Finally If you have anything you’d like to contribute to the next issue or if you have any thoughts you’d like to share on the future of Ragchew, please do get in touch with me at ragchew@wadarc.org.uk 73, Roger G4TNT
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PRESIDENTIAL PONDERINGS
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lthough I am writing these thoughts late in November 2018, I have no idea when they will be published so just in case I don’t get a chance to see you personally beforehand, I’ll take this opportunity to wish all members a very merry Christmas and a happy New Year. I didn’t use the word ‘prosperous’ as I’m pretty sure it won’t be! I must start by apologising for the absence of my Presidential Ponderings in the last issue of our magazine but my workload just didn’t give me the time to write them down. Even now that workload hasn’t decreased but I’ve somehow found the time to pen a few words for this issue. I must also apologise for not attending the AGM. This was due to problems with my car, as I will explain.
Car Trouble On the Wednesday of our AGM, I had to collect my partner Sylvia who was returning from a visit to her son in South Wales. We’d arranged to meet at Chieveley, the motorway service station at the junction of the A34 and the M4. Whilst driving up the M3 towards the A34, I suddenly heard a loud bang from the rear of the car but when I looked in the mirror, I couldn’t see that I had run over anything so I carried on driving until I reached the first service station on the A34. I pulled in there to check everything was okay and that’s when I found my rear nearside tyre was punctured. However, it was not entyrely (sorry) flat and as it was a run-flat tyre, I decided to carry on with my drive to Chieveley. It took a lot longer than usual because I had to stick to between 40 and 50mph to stop the tyre overheating. After collecting Sylvia and her luggage, we then had to drive all the way home at the same speed. I suppose the total distance would have been about 130 to 140 miles so this took quite a while, much to the annoyance of some other drivers and it wasn’t helped by having to stop every so often to let the tyre cool down. If any member is considering getting run-flat tyres, I’ve found they can be a mixed blessing. They’re very useful when you do get a puncture but
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C the other side of the coin is that they usually cost more to buy initially and once they’ve been punctured, they can’t be repaired. I guess that incident cost me an extra £150 and a missed AGM.
Joke I am including the following joke in the hope that it will extract a laugh from those who read this epistle. A married couple went to their doctor’s surgery because the husband was complaining of severe shivers and general debility. The doctor gave the man a thorough examination, ran several tests on him and measured his heart rate, blood pressure and so on. When he’d finished, he asked the man to wait where he was for a few minutes. He then asked the wife to follow him into another room for a chat. There he told her that her husband was seriously ill but there was a remedy. He said, “Your husband is suffering from an uncommon but very severe stress disorder that could kill him. Luckily, the remedy is simply to remove his stress but if you don’t do the following, he will almost certainly die. “Each morning fix him a healthy breakfast, for lunch prepare a nutritious meal and for dinner cook him an especially nice meal. Above all, you should be pleasant at all times and there should be no nagging and no chores. Especially important is that you make love several times a week as this is a great way of relieving stress. Do this for the next year and he will regain his health completely.” The wife then rejoined her husband and the couple left the surgery. On the way home, the husband asked his wife, “When the doctor took you aside, what did he say?” She replied, “You’re going to Die!” With that, I hope, frivolous end to this quarter’s Presidential Ponderings I wish you all loads of DX and happiness. 73, Chris G3UFS
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CHAIRMAN’S CHATTER
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s I write this, Christmas is fast approaching but by the time it reaches you, the festive season will be over so let me wish all WADARC members a belated Merry Christmas and a Happy New Year. I hope you all got everything you wished for.
New Venue When I last wrote for Ragchew, I mentioned that our current venue at Lions Hall in Lancing was suiting our purpose. Unfortunately, since then things have changed and it’s become quite clear that we are not welcome by local residents, especially when it comes to car parking. We have been losing members recently and I’m sure this has partly been due to the lack of nearby parking at our weekly meetings. Fortunately, we’ve found a solution to this problem. We’ve just signed up for a tenancy at TS Vanguard, which is the HQ of Worthing Sea Cadets. It’s a great venue with more facilities and although moving there has meant we’ve had to change to Tuesdays for WADARC meeting nights, the decision is already proving to be popular with our members. Two things that are very much in our favour are that there is on-site parking available and we will have full use of a radio room. I am quite excited about the prospect of having a dedicated shack that we can operate from – and having permanent antennas always available as well! I really hope that this move will rejuvenate the Club by helping us regain some of our past members as well as recruiting new ones. Once we’ve fully moved in, we’ll be setting up our own shack and I’d really like to see plenty of members getting involved in building the shack, especially those who are relatively new to amateur radio and who may not have set up a permanent radio station before.
Ideas Wanted Of course, a new shack and meeting place is not the entire story for WADARC and the Committee has been discussing things the Club could
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C do on meeting nights. Graham G8BZL has volunteered to send out a questionnaire to find out what would be popular and I hope that you will all help to make it a success by contributing to it with your ideas. That said, ideas need following up and I’d like each of you to also consider whether you could organise one event, pass on information about known speakers or maybe you could give a short talk or demonstration yourself.
70th Anniversary It’s just over 70 years on from the very first WADARC meeting, which was on September 2nd 1948 at Oliver’s Café in South Farm Road Worthing, and I believe the future of the Club is now looking bright. We’re even putting on a special event station using the callsign GB5WOR (thanks Graham) to commemorate the anniversary. I hope that all members will try to get involved with the event in some way, even if it’s just working the station from home on as many bands as you can. Onwards and Upwards – let’s all do what we can to make WADARC thrive in 2019. 73, Alan G4GNX
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FEATURE GB8SL FOR ILLW Edmund M0MNG reports on GB8SL (Shoreham Lighthouse), the special event station that WADARC members operated for the International Lighthouse and Lightship Weekend.
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he International Lighthouse and Lightship Weekend (ILLW) takes place every year during the third weekend in August. Full details of the event can be found on its comprehensive official website is at www.illw.net Once again WADARC put GB8SL (Shoreham Lighthouse) on the air during both days – although we always closed down overnight. Equipment This year we used the Club’s Elecraft K3 and a Tokyo linear amplifier to produce the maximum legal 400W. In 2017 we used the Icom IC-7300 and the decision to change rigs this time was mainly due to QRM from the nearby medium wave broadcast transmitter mast. It is situated just a fraction of a mile as the crow flies from Shoreham Lighthouse and it currently radiates four services. There used to be five but BBC Sussex on 1485kHz closed down as scheduled in January 2018. Shoreham Lighthouse with the problem MW transmitter mast in the background. The most powerful remaining station is TalkSport on 1053kHz. This station is reputed to have an e.m.r.p (ERP relative to a monopole) of 2.1kW. I say “reputed” because I’ve found it very difficult to pin down a definitive source of information about this mast or its operator on the internet.
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C There are very few rigs that could be expected to deal with field strengths like that and the fact that the IC-7300 suffered from small amounts of breakthrough is in no way a criticism of that rig. However, the Elecraft K3 coped admirably; I did not hear any QRM at all that I could attribute to the mast. There was some other wide QRM the whole weekend centred on 7.130MHz but that was reported on the DX Cluster from as far away as Italy and it sounded like an over-the-horizon radar. Our antenna was our usual multi-band trapped dipole with one end tied to the railings at the top of Shoreham Lighthouse. Usually, we tie the other end of the dipole to a conveniently-located telegraph pole that is shorter than the mast holding up the middle of the antenna, which causes one leg of the dipole to slope downwards slightly. This year we used a pump-up mast in place of the telegraph pole, which made the entire dipole perfectly horizontal at roughly 45 feet above the ground. I do not know how much of an improvement this configuration made by itself, but it certainly did us no harm. In the past we have used Norman 2E0RKO’s pump-up mast to support the middle of the dipole. I don’t know if Norman lent us his mast this year or if we used a different one but thank you Norman if it was yours! On the Air The official ILLW event runs from 0001z on the Saturday until 2359z on the Sunday but many lighthouses like to test their stations on the Friday evening so we decided to do the same. We started testing our setup on Friday and by the time we’d finished, we ended up making 30 QSOs. Two of those were into Brazil but the highlight for us was when ZS1FRC, the Slangkop Lighthouse (ZA0015), called us on 40m. South Africa ended up being our best DX of the whole weekend despite the QSO happening a couple of hours before the ILLW officially started! We made all our contacts using SSB and almost all were on 40m, apart from a handful on 20m and a couple on 80m when Phil G4UDU came down to take part in Sunday morning nets. We managed to work the
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C United Arab Emirates and Lebanon in addition to Brazil and South Africa, but the rest of our contacts were all inside Europe. Last year 40m suffered from extremely deep and rapid QSB, especially where signals had been very strong initially. The trend this year was for signals to be very weak but consistently so. QSB was present at times but nowhere near on the scale of 2017. On Saturday afternoon the skip distance shortened for many hours and that allowed us to make a lot of contacts within the UK; this made a pleasant change from the year before. Unusually propagation also ran towards Spain sometimes, as well as the more usual countries such as France and Germany. These are the three foreign languages that I speak so I had my work cut out! Even the weather was kind to us. There was no rain but, more importantly, the temperature was comfortable. The operating tent would have been extremely hot and humid if the heatwave we experienced throughout July and the first half of August had not ended. Mercifully the temperature dropped significantly just in time for the ILLW. Contacts We made 482 contacts on HF altogether which included 34 lighthouses. In 2017 we made around 300 contacts but we worked nearer 40 lighthouses. Scotland was in the lead this time with nine and England and Germany came joint second with five lighthouses each. I did make a handful of contacts on 70cms via the GB3LR repeater at Newhaven and through WADARC’s own repeater GB3WO. GB3LR brought a contact with GB0NL at Newhaven Lighthouse, which made them the only lighthouse we worked on both 40m and UHF.
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C The output of GB3WO was not very strong at the foot of Shoreham Lighthouse, even using my 4-element ‘Yagi on a stick’, which claims to have 7dBd gain. Less than 24 hours after the ILLW finished, the repeater was moved to its new home at Worthing Town Hall. Unbeknown to me at the time, the transmissions from GB8SL on the Sunday afternoon are likely to have been some of the very last through the repeater at its old location. DigiModes Whenever GB8SL was on the air, I transmitted APRS from my car on 144.800MHz using my Yaesu handheld and a 7/8ths wavelength whip. John G8FMJ kindly gave me this antenna years ago to save it from ANPR Location gathering dust in his garage! I was surprised to see that APRS is so accurate that the website (www.aprs.fi) placed the lighthouse icon in the exact spot where my car was parked, rather than at the lighthouse itself! During one QSO on HF, the operator mentioned that he had seen the APRS transmission so he knew exactly where we were and what we were doing. From the Friday to the Sunday afternoon, I also ran a 200mW WSPR beacon continuously on 30m. This was partly for publicity but also to have an idea of the prevailing propagation conditions. My linked SOTAbeams dipole was in an inverted-V configuration with a short squid-pole holding it up in the middle. Many thanks to Roger G7VBR for helping me to put it up. It didn’t fall down or get blown over even once! I don’t remember GB8SL ever using 30m in previous years and my antenna was at right-angles to our ‘main’ antenna. Despite the two antennas being in relatively close proximity and the high levels of RF in the area from the main GB8SL station and the Southwick MF transmitter, I am pleased to report that my WSPRLite Classic survived unscathed. If
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C too much ‘reverse RF’ enters the device, it can become impossible to reprogram it. Not that it would have been the end of the world – I would have simply used it once per year on the ILLW on 10MHz. The saying goes that ‘30m is always open to somewhere’ and this time that proved to be the case. WSPR on 30m Every single one of my WSPR transmissions was received; the band did not close completely during the whole 48 hours – not even briefly in the middle of the night. The transmissions were heard from Iceland down to the Canary Islands, across to the Balkans and up to the Arctic Circle. A few of them even found their way across to the eastern coast of the USA. Finally My thanks as ever must go to the Shoreham Rowing Club for providing us with mains electricity and for the use of their facilities every year. Thanks also to fellow members of WADARC and local radio amateurs who visited us or worked us. I am afraid that I did not keep a list so I will not attempt to name them all in case I leave anybody out by accident! The main operators though were Pete G4LKW, Steve G4TPO along with Ed M0MNG (me). In addition, Roger G7VBR did a wonderful job at keeping us all well fed and watered. I must also thank G4LKW and G7VBR for helping to put up and take down my own tent. Once again I camped outside of the main operating tent, which gave the impression I was some kind of guard dog inside my kennel. I hardly slept at all the first night and slept like a baby the second night, which was an exact repeat of 2017. Last year I blamed the strong
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C winds overnight for making my tent flap and keeping me awake but this year I will have to find a different excuse for no sleep the first night!
GB8SL first went on the air in 1999 and I am looking forward to our forthcoming anniversary in 2019 and hoping that we’ll be able to make it a record-breaking year! If you’d like to learn more about this event, I have made a YouTube video that can be viewed at: https://www.youtube.com/watch?v=KBhGg9CFdxE 73, from Ed M0MNG on behalf of the GB8SL team.
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G1EXG’S SHORT CIRCUITS This time Jonathan G1EXG takes a look at varicap diodes and explains what they are, how they work, what they do and how they are used. SHORT CIRCUIT NO. 20: VARICAP DIODES
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varicap diode is a type of diode that can be used as a voltage controlled capacitor. It is useful for tuneable filters, amplifiers and in oscillators used in radio circuits. An ordinary diode is an electronic component that only conducts when the voltage is correctly applied to it, that is, when the cathode is negative and the anode is positive. When connected the other way around, the device is said to be reverse biased and very little current flows. How They Work Inside the diode there exists a region called the depletion zone. This is effectively an insulated region between the junctions and it’s the part that makes the diode behave like a capacitor. Its size can be altered by varying the voltage applied to it. The greater the reverse voltage the greater the size of this depleted region and the smaller the resulting capacitance. Therefore, by changing the reverse voltage you can adjust the internal capacitance of the diode – you have a voltage controlled capacitor. All diodes behave like this but by carefully controlling the diode fabrication process you can deliberately create a variable capacitor diode that has much better reproducible properties, a wider reverse voltage range, better temperature stability properties and fewer losses than a standard diode (better Q). These specially made voltage controlled capacitors are called varicap diodes, varactor diodes, variable capacitance diodes or tuning diodes. Varicap diodes are much smaller and far more convenient than an equivalent mechanical system such as a variable capacitor driven by a motor or servo system for example because they respond faster and take
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C far less power. You can conveniently use varicap diodes to create resonant circuits in filters, oscillators and a range of other radio related applications. Type BB112 V149 BB212 NTE617 MV104 MBD102
Range (pf) 20-520 20-500 22-620 34-39 37-42 few pf
Applications (1-8V) mw / sw radios (1-8V) mw / sw radios (1-8V) dual varicap dual varicap, FM tuning dual varicap, FM tuning varactor tripler (see text below)
In Use The varicap capacitance is controlled using a DC voltage but one potential problem (no pun intended) is that in radio applications the RF voltage itself might modulate this reverse bias voltage, which could create unwanted detuning and distortion (see below). To reduce this problem, the RF levels in the circuits should usually be kept quite low and this is why varicaps tend to be used in input stages, preamps and oscillator stages but not in power amplifier stages for example. Two varicap diodes can be used back-to-back (in series) to half the voltage across each device but, unfortunately, doing that also halves the capacitance range possible. These double varicaps are often packaged in a three-lead transistor-style case (for example, the BB212 double varicap uses a T0-92 case) with a common connection on the centre pin. Circuits The first circuit shows a dual-varicap tuned oscillator circuit (in this case with the two varicaps wired in parallel) that can be used in voltage controlled oscillators (such as those used in a spectrum analyser) and frequency synthesisers that are used in transceivers and so on.
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C If you couple an audio signal from a microphone into the varicap control voltage line (AF i/p on the diagram), you can create frequency modulation and at high frequencies (where the capacitance change that’s required is very small), even a standard diode such as a 1N4148 or a 1N4001 can be used instead. In a previous Short Circuit article I described a simple receiving loop that can help reduce picking up local noise. It used a variable capacitor to tune it. Here, I show a varicap tuned version. The diode is attached close to the loop and it can conveniently be tuned using a control voltage cable from the shack so there is no need for a costly and cumbersome waterproofed motor driven capacitor and waterproof box to be fitted outside with the loop. To ensure good reception, you need to make sure that the long varicap control voltage wires do not act as antennas that could introduce rogue signals into the loop circuit. As very little current flows when the diode is reverse biased, a simple resistance, capacitor (and inductor) circuit can be used to effectively decouple the control cable wires (but it needs to be fitted close to the loop and varicap tuning diode). You can also use the coax to feed the DC varicap diode control voltage if you make up a suitable decoupling circuit. Microwave Generators The distortion created in a varicap circuit by large RF voltages can actually be put to good use to create harmonics. This allows varicap diodes to be used as frequency multipliers (e.g. triplers) to create SHF and microwave frequencies that would be difficult, costly or impossible to generate with current transistors. 73, Jonathan G1EXG
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RALLIES WINTER 2019 JANUARY 27th – Horncastle Amateur Radio & Electronics Rally Horncastle youth Centre, Cagthorpe Buildings, Willow Row, Horncastle LN9
FEBRUARY 3rd – Sears 35th Canvey Radio & Electronics Rally Cornelius Vermuyden School, Dinant Avenue, Canvey Island SS8 9QS 8-10th – Orlando HamCation Central Florida Fairgrounds, 4603 West Colonial Drive, Orlando, Florida, USA 10th – Harwell Radio and Electronics Rally Didcot Leisure Centre, Mereland Road, Didcot, Oxon OX11 8AY 17th – Radioactive Rally Nantwich Civic Hall, Cheshire CW5 5DG 24th – Rainham Radio Rally The Victory Academy, Magpie Hall Road, Chatham, Kent ME4 5JB 24th – Red Rose Rally St Josephs Hall, Chapel Street, Leigh WN7 2PQ
MARCH 3rd – Exeter Radio & Electronics Rally America Hall, De la Rue Way, Pinhoe, Exeter EX4 8PW 16th – Laugharne Rally Laugharne Millennium Memorial Hall, Clifton Street, Laugharne, Wales SA33 17th – Wythall Radio Club Hamfest Club HQ, Wythall House, Silver Street,Wythall B47 6LZ 24th – Hamzilla Radio Fest And Electronics Fair Discovery Science Park, Gateway House, Ramsgate Rd, Sandwich, CT13 9FF 24th – Callington Radio Rally Callington Town Hall, Callington, Cornwall PL17 7BD
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