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The newsletter of Cockenzie & Port Seton Amateur Radio Club

March 2010 Vol 18 Issue 3

EDITORIAL By Bob Glasgow GM4UYZ Onto another month and another editorial, already this is the third one for this year, my how time flies by!!!! One thing is noticeable and that the evenings are now beginning to ―stretch out‖ and aiming away from what I call the winter doldrums. Thank goodness for that say‘s I. In some respects I like the dark nights where one can get nice and cosy sitting watching the television but if I am perfectly honest I do prefer the light nights as it allows one to get out and about instead of vegetating in front of the ―box‖. First of all this month I would like to pass on our deepest sympathies to Arthur 2M0BUX who sadly lost his mother the evening before he sat his Advanced Exam. It is a difficult time for all of those concerned trying to come to terms with their grief so all we can do is be there for them and offer our sympathies. Ok then what have we been up to this month; first of all we had our annual radio check night run by John MM0JXI. It is a great event to put your radios through their paces so hopefully many turned up to take part. Also we have had our Trap construction night and perhaps some of the attendees could write a small

article for the newsletter on how they got on. Tomorrow, 6th March, I start another Intermediate Course my last course for this term before I take a well earned rest, I certainly feel I need it, before I start up again in September. My February Foundation Course will be finished and the 9 pupils will have sat their exam On behalf of us all I wish them all the best with their respective exams. To the future, I have still to arrange all the dates yet for my 2010-2011 sessions and once I have done that I will announce them via the newsletter and our website. Our next event in March is a talk by Paul Henderson 2M0BUY on ―Forensic Science‖. This will be held in the Port Seton Community Centre Resources Room on the 19th March between 19:30 and 21:30. I do hope many of you will make the effort to come along as I for one appreciate the amount of effort that is required to put on even a 30 minute presentation. To the future for the 10 Pin Bowling in April (Saturday 17th April @20:00 Ten-Pin at Fountainbridge: Cost £12.00 adult £10/child) there are still plenty places if you wish to go so if

you do can you please contact me direct. It is important that I get a £5 deposit per person as I have not booked it yet as they have changed their policy i.e. you book and pay immediately and if you cancel you lose your money. Lastly, if I have any thing to say this month it is the old hobby horse of looking for newsletter input. Thanks to those who have been contributing but we need more. Lots of people indicate that they will but never do. I do struggle from month to month to write articles and I really genuinely could do with some help so this is a plea from the heart for articles. It would be fantastic to have a good pool of articles that John can select from. Right, I think that is about it so enjoy club night and the newsletter. Bob GM4UYZ

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Lothians RAYNET By Malcolm Gibson MM0YMG I joined Lothians RAYNET about a year ago and whilst I accept it would not suit everyone it has given me a lot of enjoyment and a completely different sort of radio use. I believe it has helped me broaden my experience and has sharpened up my operating procedures considerably. The concept of Lothians RAYNET is to for licensed amateur radio users to provide the Edinburgh and Lothians Emergency Planning Department with a structured and robust radio communications capability in the event of a major situation where normal lines of communication, i.e. mobile phones, are disrupted or overwhelmed. To this end it is one small part of the substantial national resilience planning. There are about twenty members of Lothians RAYNET all of whom undertake training in quite specific voice procedure protocols to ensure maximum clarity of communication with minimum use of air time so as to conserve battery power since mains power may not be readily available and batteries are only of finite capacity. We test equipment, practice the voice procedures, and also handling messages, on a weekly Sunday sked. During the year we participate in a number of events, especially en-

durance horse riding events, where we are able to provide reliable and robust communications to aid safety since many of the events take place where there is only sporadic mobile coverage. The events also serve well as practice exercises for us so everyone gets used to the procedures for setting up, and closing down the communications net; practiced at adapting their portable stations to optimise reception; and configuring equipment to utilise our own simplex or duplex, depending on conditions, talk-through repeater operation. Usually you are on your own at a station so you become entirely responsible for your own health and safety issues, plus having the resources to get on the air (mostly on 2m and 70cm), stay on the air, and most importantly get back on as quickly as possible in the case of some failure. So you have to get to know your rig, practice using a variety of antennas, and become adept at field repairs. Having a Land Rover just adds to the fun since we tend to get sent to the more interesting outposts of the net so I have spent many enjoyable hours in the middle of forests with my portable antenna up, playing radio, drinking coffee, admiring the view, and monitoring

riders as they go through the check points. Of course it does sometimes rain, and the midge net is never very far away, but it has still been huge fun. For all that you are often on your own, you are also very much part of a team, and a team that will help you out to the nth degree. The similarities between being on a RAYNET exercise and being a part of the CPSARC Contest Group are quite striking – both go out of their way to help newcomers; both groups have a vast depth of skills and knowledge at their disposal; both groups work very effectively as a team. The only difference is that the objectives of each group are, on the surface, different – RAYNET to create robust yet flexible communications net and the Contest Group, well now I think of it, to create robust yet flexible communications net but to a slightly different end! So far the 0330h emergency telephone call has never come and hopefully it won‘t; but if it does then I know where my grab bags, with maps, torches, spare radio bits, portable antennas, hi-vis vest, hat, gloves and first aid kit etc are, as well as just what kit I need to extricate from my shack and will be ready to turn up with batteries all charged, and hopefully will have had enough time to have filled the Thermos with life saving hot coffee! MM0YMG 2

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10 Pin Bowling Night 10-Pin Bowling Night on Saturday 17th April @ 20:00 at the ―Ten-Pin‖ Venue at Fountainbridge, Edinburgh.

Contents 2. 3. 4. 5.

2 GAMES OF BOWLING Cost: £12.00 Adults £10.00 Children. Note: Built into this cost is a small amount of money to allow me to buy some prizes… Parking is also free by getting your car park ticket cleared at the TenPin Reception desk.

6. 8. 10. 11.

Lothians RAYNET 10 Pin Bowling So, now you have got a licence... A beginners guide to contesting Contesting changes over the years Radio Test Night Test Your Knowledge Event Calendar

This is a great family fun night and over the years we have had some really good nights so why not come along and take part. Like last year I have checked the date below is free and it is. The issue is that I must pay a 50% deposit within a week of making the booking, in my case I want to pay it at the time of booking (want to do on Saturday 6th March just after Club Night) as it saves me an extra journey up to Edinburgh plus the Full Payment also needs to be paid by the 10th April. Conditions of the booking are once paid there is no refund DO YOU WANT TO GO? IF SO CAN YOU LET ME KNOW HOW MANY ARE GOING with deposits or full amount, ASAP PLEASE --Thanks in advance Bob GM4UYZ

Contributions to the newsletter and web site are most welcome. Please don‘t send these items to GM4UYZ, he‘s busy enough doing the many other things he does for the club. Send any items you‘d like included to mm0jxi@cpsarc.com or submit them direct to the www.cpsarc.com The latest Foundation Licence class 33


So now you have got a Licence... By Bob Glasgow GM4UYZ Below is an article I wrote a year or so back for the club newsletter and I thought I would resurrect for the new licence holders it as it is still valid. The article is as follows: The normal question is, “what radio should I buy and what aerial do I need?” To be honest it is the thousand dollar question. It really depends on what you want to do, Are you interested in VHF or HF? What modes do you want to use, etc, etc? All the decisions really are answered normally in many, many cases at it ends up one’s financial situation that will decide. Any way all the above are a topic on its own right and will leave for another day. The decision has been made on the radio and antennas so now it is down to the operating as let us be honest we all obtained our licence so that we can communicate with others whether it is a few miles away or at the other side of the world. Again decisions start, do I just want to rag chew? Do I want to get involved contests and what they offer? Well the answer is why not combine the both. Ok I know some people will already be saying but “you love contests but they are not for everybody”, I agree whole heartily with that statement but where I am aiming is as part of your communication, why not set some targets and aim go for certain awards. More on these in a minute. What I am trying to get over is that here you are a new licensee and probably terrified to go on the air in case you make errors and make a fool of yourself and more than likely stuck for what to say. Every amateur expects in a QSO what is called the “rubber stamp” i.e. name, QTH, RST, what radio, what antenna so they will be passed. Now what do I say next, well this is where aiming for some sort of award helps as you could be

interested in DXCC countries, USA states, USA Counties, German DOK’s, worldwide locators IO85MX), etc, etc. This then leads to ask the question as part of the QSO on information that you are looking for. From experience it has led onto some lengthy QSO’s well and truly breaking the “conversation ice”. To give you an example of this, when I was first licensed back in 1983 I got interested in working Russian Oblasts (a Russian Oblast is an area within Russia equivalent if you want to our counties), why oblasts well it was after reading an interesting article in the SWM (Short Wave Magazine). If I remember correctly there were about 150 in the old Russian structure and each area was given a number, today after the restructure there are 92 areas each starting with two letters and then each area is broken down to further areas each starting with two numbers. The difference it made to the QSO was terrific and everyone was intrigued to why I was asking and as the result of this ended up with some long QSO’s. You also have to remember at this time the Cold War was in progress so it even broke those barriers down. These days I have started asking for the person’s worldwide locator as from what is given I can work out exactly where they are in the world down to a 1km square plus get the distance they are actually from my QTH. A couple of examples but hopefully it illustrate the point.

http://www.dxzone.com/cgi-bin/ dir/jump2.cgi?ID=530 The above link will take you a page where you can select a country and find out what awards are available for that country. As you will see there are many. I also have a book called “Amateur Radio Awards” by Cris Henderson G4FAM published by the RSGB. The edition I have is the third edition 1988. It no longer appears in the RSGB’s bookshop so it looks like it may have been discontinued. If anyone is interested in having a look then I could bring it along to a club night, just let me know. Enjoy your QSO’s and award hunting………… Bob GM4UYZ

As you can see from this short article by deciding on some sort of award scheme of which there are hundreds, can add a little something to the QSO. It has certainly helped me enjoy some interesting QSO’s plus at the same time learn more about different areas within the world. .

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A beginners guide to contesting—February 2010 By Robin Farrer 2M0SRF Contesting! Just like the well known brand of yeast extract. You either love them or you hate them. In my personal opinion I just can't get enough of them. It true what they say, 'contests can prove to you how well your station can perform'. It is number 1 on my list of 2010 radio related shenanigans to operate in a couple and hopefully win at least a certificate, the others are to operate more out in the open and learn a substantial amount of Morse code, anyway that is for another article. Over the next coming months I hope to take part in different contests, ranging from HF to VHF including 'backpackers' and Practical Wireless 2m contest (hoping to beat my score of 70 in 2009) and will update my progress on how well I did. I apologise if my articles may not be up to standard but hopefully It will relieve Bob UYZ of spending his hard earned free time on the newsletter. So what is my contesting background? Apart from taking part in VHF field day and CQWW with the club, I have not taken part in a contest from home until this month. When I was first licensed in 2007 I just picked out the stations that were on the bands and worked them, not knowing what a serial number or an ITU zone was and just caught on with what the other stations were given back, however it was embarrassing when you said your ITU zone was 29 and the reply came back asking if you are operating from Russia. Once you read up on information and the wide resources on the internet, it all comes clear and easy to understand.

February Contests Black Sea Contest Club: This is the first HF contest I did on the weekend of 6 February to 7 February 2010. I came by this by surprise when scanning around the bands and decided to take part for a couple of hours. Nothing gained or lost is what I thought. Overall the contest is very popular with the neighbouring black sea countries, ranging from Austria to Serbia. My category was Single OP SB 40M, Mostly stations to be worked were Ukrainians, Polish and Russians including the odd Dutch and English ops. I did manage a new DXCC for 40m 5B4AIF (Cyprus) which I have been trying to get for a while after hearing activity from the island during IOTA. Conditions were good and it was good fun, a nice easy contest to settle the beginners. PACC 2010: This contest was during the 13 and 14 February. The main ambition is to make contact with as many Dutch stations as possible. My category was Single - OP All low, with this contest conditions were absolutely dire , with QRM and QSB on all bands and with a 2M0 prefix came as a burden sometimes as some have never come across a Scottish intermediate prefix and only the usual 2E0. However a lot of operators were patient and gave me every chance to give my call out for lengthy times. It was a challenge but was perfect practice for the big club contests.

Key Contest Dates for March 2010. ('THE BIGGY' CQWW WPX SSB) 6 March – 7 March ARRL International DX Contest (SSB) 1.8mhz – 28mhz 0000 – 2359 18 March 80M Club Championship (SSB) 3.5mhz 2000 – 2130 20 March – 22 March Russian DX (CW, SSB) 1.8mhz – 28mhz 1200 – 1200 27 March - 28 March CQWW WPX SSB (SSB) 1.8mhz – 28mhz 0000 – 2359 I do plan to take part in the 80m Club Championship this month, so I will report back on my progress. Looking forward to a few sleepless nights into the wee hours of the morning and hoping to work some club members on the band. Cheers, Robin 2M0SRF (hopefully not for long!)

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Contesting changes over the years By Bob Glasgow GM4UYZ Whilst sitting down and having a cup of tea I started thinking about how contests have changed over the years. I know that contesting is not for everyone and basically you will either love or hate them. I also know that some people think of our radio club as just a contesting club and nothing else, on that statement I would like to point everyone to the Events Column to see how many contests we are actually going to take part in with relation to the other events that we are running. It is also just a fact that quite a few of us within the club are interested in doing contests so I can see from an outsiders point of view that quite a lot of talk is around the realms of contesting, which makes it look like the club‘s main interest. I really would like to dispel that myth here and now as it is not the case. Any way that is a discussion for another time. Back to contesting and what does it offer? Next is how I personally see it but I am sure others will add their respective view points as well. They are Fun and as long as you remember this, you will enjoy them. They are Competitive; remember you could win the contest!!! That is a great thrill. Remember that within a contest there are different categories i.e. QRP, Low Power, High Power, SSB only, CW only, short and long operating times, etc, etc so basically there is something to suit your station and you personally. A great chance to enhance your operating skills no matter what mode you are using. Opportunity to contact some rare countries. A great test to see how well your station is performing. You might not have the capability to put on a huge station i.e. Multiple Yagis, Multiple Radios, run High Power, but as long as you remember

what your station limitations are you can certainly judge its performance. For each contest set your own targets i.e. this year I took part in the CQWW CW contest from home and I made 75 QSO‘s, the next time I take part in the same contest then my target will be to beat that 75 QSOs. Learn about band conditions and propagation, particularly on HF. Learn about the different operating conditions between HF and VHF. Logging skills – now computer based so definitely enhances keyboard skills. Contests can be addictive. As you can see there is a lot more to contesting than meets the eye and I am sure even I have missed some vital points from the above list but hopefully it will give you a feel on why people do it. How has it changed? I personally got involved away back in 1986 with my first ever contest being the RSGB 144MHZ & SWL Contest (17/5/1986) which lasted for 24 hours. I took part in this contest from our old VHF site at Mainslaughter Law, nr Longformacus with Ron GM4IKU, Brian GM0EHL and Russell GM0CBX. Looking at the results we made 180 QSO‘s and 62 Multipliers which even in today‘s terms is not a bad outcome. That was me ―hooked‖ as they say and I have contested ever since. My interests these days I must admit are more on HF rather on VHF and this move was basically enhanced when Foot and Mouth was at its peak in 2001 and all VHF contests from hilltops were banned. No matter where your interest lies, whether it is VHF or HF then what has changed? Operating Skill – This still remain the same.

Equipment – radios, accessories and aerials Radios have certainly changed with regard to their performances but again if you cannot afford the ―all singing all dancing‖ radios then it may not affect you as you could still be using the same old radios and their limitations. More accessories available for example Voice Recorders (certainly save the voice as I can think of contests which I have done where I am nearly lost my voice, no comments please), Band Pass Filters, Computer/ Radio control, Band Decoders, computers, etc. Aerials no real change here as Yagis, etc have been around as long as I can remember. Logging – This is where the major change has occurred – Paper to Computer. Paper Logs - When I first started contesting the only method of logging was on paper. As well as the standard paper log then for example, there were ―dupe‖, ―locator‖, ―country‖, etc sheets to be kept updated all of the time. Can you imagine how difficult that was if you were in the middle of a pile-up? It really was the case that two people were needed, one operating and one logging and updating, to do all the work. The next major problem was the standard of individual‘s hand writing, some absolutely terrific and some absolutely awful to say the least. This really became apparent after the contest was finished when everything had to be collated and checked before submitting the final paper entry to the contest adjudicators. I can assure you that there were lots of head scratching, phone calls etc to sort out. Quite often more time was spent after the contest sorting out the logs than the actual duration of the contest itself. (Continued on page 7)

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(Continued from page 6)

Computer Logs – Then contesting came into the 21st Century with regard to logging with the introduction of computers. Along with computers the Contest Software writers and subsequent logging programs appeared making contest logging a dream after paper logging. Today we use programs like G0GJV, SDV and WIN-TEST for VHF Contesting, NA/CT/TR/SD/ N1MM/Writelog/Win-TEST for HF Contesting and there may be others that I don‘t even know about. No matter what logging software that is going to be used the skill now is to ensure that it has been correctly set-up for the contest and the equipment that is going to be used. We used to use G0GJV for VHF and NA predominantly for HF contesting which had the disadvantage that it was necessary to learn two separate programs. These days for all our contesting we use WIN-TEST as our logging program basically it offers everything that is required for all contests and it is only one program to learn. WIN-TEST has the choice of separate templates for individual contests so the correct one is selected for the particular contest i.e. CQWW, RSGB IOTA, etc. WIN-TEST also has the ability to control or sense changes from your radio and log it at the same time i.e. Band Changes, Mode changes. WIN-TEST can also send CW from the keyboard or control a remotely attached Voice Recorder. WIN-TEST can also drive accessories like Band Decoders which can control Band Pass filters, etc, it can also drive Rotators and lastly WIN-TEST can be computer networked so that log entries are passed between multiple stations. During the contest is where computer logging comes into its own as it can tell you right away when you make a duplicate contact, the countries etc that you made contact with plus any other actual contest information specific to the actual contest you are taking part in. Having the ability

to do CW and control a Voice Recorder from the keyboard makes it a lot more easier for a single person to actually log, what the operator now really has to do now is concentrate on their typing skills, yes we can still get typing errors. Another area where the computer log is supreme is after the contest where in reality all you need to do as soon as the contest is finished is email your log to the contest adjudicators. To be honest the logs are always checked for mistypes, etc before submission but this after the contest is absolutely minimal compared to the old paper logging. Paper logging I would never ever do again….. Operators and logging – If there is any down side with regard to computer logging compared to paper logging it is that of the operators. Those who are not used to using computer keyboards definitely shy away from operating and to be honest I can understand why particularly if they get hit with a pile-up. I suppose the answer is ―get practicing your keyboard skills‖, but to be truthful the real answer is just take control of your actions. If you are the focus of the pile-up then as you go back to the station who called you, type in his callsign as you go back, what I mean is if VK2ABC called then when you answer each letter of the callsign then type it in, so you would be saying V, then type V, say K then type K, etc. Yes it is slow but the more you do it the faster you become. If you are doing Search and Pounce then type in the station you are going to call before you call them. Also I would recommend that you do some contests on your own and practice the Search and Pounce technique if nothing else it will give you confidence in using the keyboard. Lastly another skill the operator needs to learn is picking spots from the ―Band Map‖ that is filled from a DX Cluster input (assuming it is available). These spots can be just a new contact but they can also be a new

country or even multiplier so worth lots of points. If I do have a tip for these operators, it is remove the pen and paper and just use the keyboard. It is amazing how after a short while you will not miss them at all. Submitted Logs – As mentioned earlier that when using paper logs it all had to be collated and then sent away and believe you me it was hard work. With computer logs it is really all about finishing the contest and immediately submitting your log, as mentioned earlier you really wouldn‘t do that without giving it a check over. What computer logging offers for the adjudicators is that cross checking is made easier and from our point of view the results are out sooner. What also has occurred is that the need for the entrant to do his own scoring has now disappeared as now a standard log entry is submitted as a file called Cabrillo. This file is what is used for all the checking plus the adjudicators now automatically rescore the submitted logs. In many ways this again has made life easier from our point of view plus as well for the Logging Software Writers. Progress as they say. I am sure that I have more than likely not covered everything but hopefully you can see some of the changes that have been made from what I call the old days, no matter what go out and give contesting a go you may just enjoy it. Bob GM4UYZ

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Radio Test Night By John Innes MM0JXI On Friday 19 February 2010 I held the latest in my series of radio test nights at the Port Seton Community Centre. Here I am using professional test gear to check out various pieces of amateur radio equipment. This gives club members the chance to have the regular checks required by their licence conditions to ensure that their equipment is working correctly and not producing any undue interference. The equipment for these test nights has been provided through my work in BT‘s Technical Support Group and consisted of a Marconi 2955 Radiocomms test set, an HP 8652A Spectrum Analyser, a Bird 43 Thruline wattmeter and dummy load. Using this equipment I can test a variety of parameters to ensure that a particular piece of equipment is performing within it‘s specifications.

Marconi 2955 Radiocomms test set Transmitters Transmit power (up to 400W) Frequency (up to 1GHz) Modulation depth Sub-audible tones (CTCSS) Tone bursts Spectral purity Receivers Sensitivity (SINAD) Frequency accuracy

CTCSS operation Audio distortion Test methods Unfortunately, no single piece of test gear I have can perform all these tests, the 2955 is very flexible but is limited to 30W input power so when I want to measure higher powers I have to employ the Bird Thruline wattmeter with its selection of measurement elements which allows me to measure RF up to 100W at 450MHz and 500W at HF Frequencies. I transmit through the Bird Thruline into a dummy load capable of handling all the RF I can throw at it. The spectrum analyser is designed to measure very small signals over a huge bandwidth so needs to be isolated from very large RF signals and this is done by using an RF sniffer which samples a tiny portion of the transmitted signal and presents it to a third port on the device which can then be applied to the input port on the Spectrum analyser. I have two sniffers, one for HF and one for VHF and above .

To complete the test setup I used a 12v DC power supply and a series of co-axial adapters to convert the variety of connector types used on amateur radio equipment to the N and BNC type connectors on my test gear. Finally I have a custom audio lead which I use to connect the audio input on the 2955 test set to the speaker output on a radio to perform the SINAD measurements. Performing the tests I usually try to perform the tests in the same order each time. I measure the output power of the device under test on the Bird Thruline and then examine the display on the spectrum analyser for harmonics further up the frequency spectrum from the fundamental, If I see any, I can place a marker on them to read off the frequency and power level (relative to the fundamental). I then adjust the power output to below 30W and connect the radio to the Marconi 2955. In Transmitter test mode I measure the transmit frequency and then modulate the signal by (Continued on page 9)

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I could also see the SINAD value rise as I reduced the input level.

(Continued from page 8)

whistling into the microphone to measure the modulation depth. I then match the transmit and receive frequencies before switching to the Receive test mode (this prevents me having to manually enter the receive frequency as every radio is set to something different) In receive mode I turn off the radio squelch and connect up the speaker output to the audio input on the 2955. I then adjust the receive input level while watching the SINAD display until it reads 12dB SINAD and note the RF input level. SINAD itself is a measure of the ratio between the received audio signal (plus noise) and the noise remaining when the modulating signal is removed 12dB SINAD is the standard generally used to determine the sensitivity of a receiver, at that value speech is still intelligible although some manufacturers

skew their spec sheets by quoting levels relative to 10dB SINAD which is a little easier to achieve and makes their equipment look at little better on paper. The general rule of thumb is that an input level of 0.4µV for HF and 0.2µV for VHF/UHF radios is acceptable. If the owner wants CTCSS or tone bursts checked I can do it at this point. Examples Malcolm MM0YMG had brought along his new FT2000 which he suspected was a little deaf, tests showed that the performance wasn‘t great but examining the controls showed that the RF preamp was on the wrong setting, correcting this brought the sensitivity figures back to the normal values we‘d expect. The rest of the radio tested perfectly so I was able to reassure him there was no fault with the radio.

So, thanks to everyone who brought along radios to be tested and showed so much interest in the testing process. These test nights are very intense but also very satisfying. I hope everyone went away satisfied that their equipment is working correctly, I saw no serious faults, although one radio, an FT-920 owned by Gary MM0FZV was showing spikes at the 2nd and 3rd harmonics but they were still below the –50dB spec for that radio. More modern radios can expect to have harmonic products below –60dB. While writing this article, I looked up the spec for the FT-902 and the more recent FT-2000, this really showed the improvements made in recent years. FT-920

FT-2000

Introduced

1997

2009

Frequency Stability

10ppm

0.5ppm

Harmonic Radiation

-50dB

-60dB

SSB Carrier -40dB suppression

-60dB

Sensitivity

0.2uV

0.2uV

John MM0JXI

Bob GM4UYZ challenged my testing by bringing along a home brew RF attenuator wanting to know if it worked correctly. I was able to demonstrate that the attenuator did work by applying a signal to a radio through the attenuator and watching the S meter on the radio while I operated the various switches. 9


Test Your Knowledge By Bob Glasgow GM4UYZ 1. a. b. c. d.

Harmonic radiation from a transmitter may be reduced by Adjusting the receiver‘s audio gain control setting Fitting a low pass filter in the antenna feeder to the transmitter Placing a high pass filter in the mains lead The state of the sunspot cycle

6.

a. b. c. d. 7.

2.

The drawing shows a block diagram of a TRF (Straight) receiver. Which one of the blocks selects the radio signal?

Tuned

Detec-

Audio

Headphones

a. b. c. d. 8.

a. b. c. d.

Tuned circuit Detector Audio amplifier Headphones

3.

a. b. c. d.

A radio receiver is set to receive a signal of 14.1 MHz and the local oscillator is set to a frequency of 13.6 MHz. What will the intermediate frequency be? 500kHz 13.6MHz 14.1MHz 27.8MHz

4. a. b. c. d.

The demodulator for a FM receiver Requires a beat frequency oscillator Requires a narrow band pass filter Could be a frequency discriminator Could be an envelope detector

5.

The block diagram shows a Morse Code transmitter. Which one of the following does block X represent?

a. b. c. d.

AF Oscillator RF Oscillator Demodulator Modulator

a. b. c. d. 9.

a. b. c. d.

A carrier wave on 28400 KHz is amplitude modulated. The upper sideband is 28402KHz the lower sideband is 28396KHz 28398KHz 28404KHz 28406KHz A station in the 23cm band is being interfered with by an amateur transmitter on the 70cm band. This could be due to the Receiver audio gain control setting Transmitter using narrow band FM Presence of a harmonic in the transmitter output State of the sun spot cycle To minimise the radiation of harmonics, which one of the following filters might be fitted between the transmitter output and antenna? High pass Key click Braid breaker Low pass The drawing shows a block diagram of a simple Superhetrodyne receiver. What is the block marked X?

Detector Audio amplifier Tuned RF amplifier Loudspeaker

10. The intermediate frequency of a superhet receiver is the a. The sum of the RF and the local oscillator frequencies b. Difference between the RF and the local oscillator frequencies c. Sum or the difference between the AF and the local oscillator frequencies d. Sum or the difference between the RF and the local oscillator frequencies

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Event Calendar By John Innes MM0JXI

5 March 2010

Club Night

6/7 March 2010

ARRL International DC Contest (SSB)

18 March 2010

80m Club Championship (SSB)

19 March 2010

Talk by Paul Henderson 2M0BUY ‗Forensic Science‘

20/22 March 2010

Russian DX Contest (CW, SSB)

27/28 March 2010

CQWW WPX SSB Contest

27 March 2010

Newsletter Deadline

2 April 2010

Club Night

17 April 2010

10 Pin Bowling Night—Megabowl, Fountainbridge 20.00

1 May 2010

Newsletter Deadline

7 May 2010

Club Night

14 May 2010

1st 144MHz DF hunt

29 May 2010

Newsletter Deadline

4 June 2010

Club Night

12 June 2010

Port Seton Gala Day

13 June 2010

Practical Wireless 144MHz QRP Contest

19/20 June 2010

Museums on the Air weekend from Museum of Flight, East Fortune GB2MOF

19 June 2010

Newsletter Deadline

23 June 2010

CPSARC 20 Activity Night

25 June 2010

July Club Night *** moved to accommodate VHF Field Day ***

3 / 4 July 2010

RSGB VHF Field Day

24 / 25 July

RSG IOTA Contest from Tiree GM2T

31 July 2010

Newsletter Deadline

6 August 2010

Club Night

13 August 2010

17th Annual Mini-Rally

21 / 22 August 2010

Lighthouses Weekend from Barns Ness GB2LBN

28 August 2010

Newsletter Deadline 11


Club Attire

Information

The club has a design for Club Tee-shirts, Polo-shirts, SweatShirts, Fleeces and Jackets and all of these can be obtained from the address below.

The Cockenzie & Port Seton Amateur Radio Club is affiliated to the Radio Society of Great Britain and holds the call signs MM0CPS and GM2T which are used for our special event and contest entries. We have our own website www.cpsarc.com where you will find our popular web site which features lively discussion forums and photo galleries. You can also download an electronic copy of this newsletter and archived copies from the past. The Club was formed by Bob Glasgow GM4UYZ in 1984, to help the local amateurs get to know each other. Far from being just a local club we have members regularly attending from the Borders, Dumfries, Strathclyde, Fife and Newcastle. The Club meets on the first Friday of every month (Second Friday of January) in the lounge of the Thorntree Inn on the old Cockenzie High Street from 7pm till late. The Club is run in a very informal way, just a group of like minded people doing something they enjoy! This does not mean that we don‘t do anything, we enter (and win!) contests, train newcomers, hold talks and video nights and run a popular annual Junk Sale. Our newsletter has won the Practical Wireless ‗Spotlight‘ competition on several occasions. The Club supports the British Heart Foundation in memory of a member who died from heart disease by donating the profits from some of the events we hold, we have raised over £14,368 since 1994.

When making an order please:  Quote Cockenzie & Port Seton Amateur Radio Club as this will ensure that the Club Logo will be placed on the required ordered garments.  If you wish to add your callsign to the logo then please ask at the time of the order. Cost will depend on garment and should cover the garment and logo, call-sign addition will be extra. Order from: PATRICIA BEWSEY DESIGNS, UNIT 11, FENTON BARNS RETAIL VILLAGE, FENTON BARNS, NORTH BERWICK, EAST LOTHIAN EH39 5BW Tel/Fax: 01620 850788 Mobile: 07970 920431

Contacts Bob Glasgow 7 Castle Terrace Port Seton East Lothian EH32 0EE Phone: 01875 811723 E-mail: gm4uyz@cpsarc.com General correspondence, training and contest entries Bob Glasgow gm4uyz@cpsarc.com HF Contests Cambell Stevenson mm0dxc@aol.com VHF Contests John MacLean mm0ccc@cpsarc.com Newsletter, website, event calendar John Innes mm0jxi@cpsarc.com Club Tables Bob Purves gm4ikt@cpsarc.com

Supported by BT Community Champions

1B, 2A, 3A, 4C, 5B, 6B, 7C, 8D, 9A, 10D Answers from March 2010 newsletter ―Test Your Knowledge‖.

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www.cpsarc.com


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