AmateurRadio.com

Next week a new semester is starting. They gave me more hours to teach, which means more income, but less time to spend on fun things. So I really wanted to finish another project and this week was just the time to do it: an audio filter. In my younger years one of the few kits I build was an notch/bandpass filter. Later I bought the Datong FL-2 and FL-3 filters I always thought it was a must to have one. Ever since I became a ham I thought about building one, but surprisingly there are not many design to be found on the interwebs. Elecraft sells a kit called the AF-1 and they were nice enough to put the schematics on their site. So I gathered the parts and put quite some hours of work in building it according to my own lay-out. The result……

It worked….sort of. But not as advertised on YouTube. I should have known better, so I cleaned up my desk and started anew. Neat and tidy this time and in modules. First up, the power section. Now, how about this?

That’s the way I like it. It worked first time, delivering 12 and 6 Volts. But I’m afraid this is going to be another long term project. Stay tuned.

By the way, after only 41 days I already achieved 25% in the FISTS 25th anniversary Prefix award. The goal is to make 25 CW contacts for each prefix number. Funny to see which number is most issued and thus easiest to score. “7 is up front with 11 entries, closely followed by number 3 with a very respectable 10 entries.” I really have to start looking out for more number six stations. If you have a 6 in your prefix then don’t forget to call me, please.

Over the Chinese New Year’s holiday I managed to start and (almost) finish a project I have been brooding over for months: a Cobweb antenna. Lightweight, small, multi-band, no tuning needed, in one-word “ideal.” There was a very interesting thread over at QRZ.com about building one and I read all the other literature I could find on the subject. I finally settled for the alternative design by G3TXQ using single wire dipoles which would be easier to tune, but required a balun for impedance transformation.

I’m still on a very tight budget, so the antenna had to be build on the cheap. That means thinking outside the box and starting with taking a good look around you. Fishing rods are expensive here. The cheapest I could find were almost 400 NT dollars per piece. But hey, we’re in Asia: bamboo is cheap, but it is also strong and lightweight. So I spend 200 NT dollars (5 euro’s or 7.50 USD) on bamboo instead of 2000 NT on fishing rods. Aluminium is hard to get in Taiwan, because people find it too soft. Stainless steel is widely used, so the local iron monger cut me two pieces for a little less than 200 NT dollars. U-bolts were also cheap at the local hardware store. Twin lead costed me 400 NT dollars for 50 meters and after two days of work it all looked like this….

The G3TXQ version requires a 1:4 balun to bring up the impedance to 50 ohms, as square folded dipoles have an impedance of 12 ohms (which every one knows, right?). The ferrite of choice is the Amidon FT140-61, but ferrite is not easy to get in Taiwan. Over in Taipei there is a little shop called RF-Parts, run by Mr. Dong, so I went to see what he got. He only had the FT-114-61, so that would mean two stacked together and that twice. Suddenly the Cobweb started to get expensive, because when I left Mr. Dong my wallet was NT$720 lighter. Add another 160 NT dollars for two meters of RG316 coax and the cost of the balun gets close to NT$1000, That’s almost more than the rest of the materials for the antenna together! But the final result looks like this….

After Chinese New Year we had two days of mild weather. Great for pruning the antenna on the balcony. Centimeter by centimeter I started cutting the wires until I had the SWR 1:1 on the frequency I wanted. The five dipoles influence each other, so it was going back and forth from 20 to 10 meters, measuring and cutting. The balcony was full of little pieces of wire afterwards, which refused to be swept up, so they were picked up by hand. But after two days the job was finally done and I could start enjoying my new creation.

NOT! Where are those sun spots when you need them? The bands were pretty empty and my first QSO was with 4W0VB in East Timor on 30 meters, at night. I know, that is not one of the band the Cobweb covers, but the TS-440S build-in tuner did it’s job well. And then it started to rain and I started to cry. Because the rain caused my carefully tuned 1:1 SWR to wander off two to 300 kHz below the resonant frequency that I tuned it for. Again, the TS-440S tuner could manage that, but why? Why does a little bit of rain de-tune my new baby? I don’t want to use a tuner. That’s not why I build the Cobweb.

I did manage to work some nice stations during the last week though: C31HA twice, 4W0VB twice more, XW3DT, PY6HD, CX3TQ and N7DR who mailed me to say I need to be patient, because conditions are indeed pretty lousy. I put up the CB whip to compare signal quality and indeed the Cobweb is quieter than a vertical. Signals are also a bit weaker, but only by one or two S-points.

So, am I happy now? No, because after the rain the wind started to play games. Longtan is not Port Martin, but it comes close. Winds howling all day long and gusts that make you and the house shiver. Longtan is situated on a plateau about 300 meters ASL and the area is known for wind and moisture. The Cobweb is light and strong, but the wires on my version were sweeping and swaying so much that SWR was not stable for a second. And the sectioned fiber glass pole that the Cobweb is mounted on was turning too much and the coax curled around it.

http://youtu.be/b5_BubymxzA

I need to start thinking about a sturdier construction. I saw some springs in a hardware store and I’m thinking about using them to keep the dipoles tight. That is the easy part, but I also need to figure out why moisture is influencing the SWR so much. Could it be the bamboo? Or is it the heavy reinforcement in the house?

I’ll keep the antenna up for another couple of days and then put the 10 meter vertical back up again. I miss roaming the upper bands at night and I want to keep my CW streak going. But a fun project it was and I learned a lot from it. And that’s what it’s all about, not?

I’ve been trying to master Morse code since 2009. I have known the basic characters since my teens, but never got the speed and I freaked out whenever I didn’t get a character, stopping cold in my tracks. I never got passed those two hurdles. So when I got my novice licence and decided to get serious about learning Morse code I read a lot about different methods, why Koch is the best, software to help you and most important, that you should be fluent in taking down the code before grabbing key.

But I always had a bit of a problem with the last one. My good friend Wouter (PG2W) was a R/O in the 1970s and his story about him going to maritime school always stuck with me. Back then would-be R/O’s started out from day one by tapping out Morse code signals on their desks, not listening to them. They weren’t stupid then, so why do I have to be fluent in taking code no before I can start sending code? “Well, simply because you can’t understand what the other is sending to you, sonny!”

True, but I am a firm believer of multi-sensory – or Auditory-Visual-Kinaesthetic (AVK) – learning. I am practising it daily in my job as ESL teacher, so I should apply it to my own learning, too. So for a while I have been sending code and checking it with help of the computer. Every now and then I would answer a CQ from a station and try my hand at a real CQ while keeping Fldigi running in the background for back-up. By constantly hearing, watching and doing I felt I was improving more than by only taking down code.

So on December 23 last year I sat down itching to have a QSO. Busy with work and family I hadn’t had a single one in 9 days. I had just put together a new keyer (the AA0ZZ one, it was on my To Do-list, remember?) and hooked up my Kent paddles to test it. The power was turned down to nil (or so I thought, later it turned out I was still putting out a Watt or two) and when I heard VK2IG calling CQ I answered him, just for fun, because I thought he would not hear me anyway. But he came back to me, went QRS to my speed of 10 wpm and we had a QSO. And all-of-a-sudden it worked! I could understand his code, take it down by hand and answer him. Whenever I didn’t catch a character I simply shrugged it off and kept on writing. I felt great, because I finally crossed those two hurdles.

So later that night I tried 80 meters for a change. In Taiwan we are allowed to operate on 3.500 to 3.5125 and 3.550 to 3.5625 MHz, so CW territory. I heard JO4CTB, answered him and it worked again. BA5HAM, no problem, although he was pretty fast and I had to use Fldigi for part of the QSO. Ever since I have been having a ball. It has been CW all the way and I am glad to say that most hams I called have been nice enough to go slow. Some QSOs have been simple RST exchanges, others short conversations. But every one helps to get me more fluent and gain speed and I enjoy every one of them.

And to set a goal for myself I decided to go for the Prefix Award, which is to celebrate the 25th Anniversary of FISTS CW Club. 250 CW QSOs of which 10 need to be with FISTS members. No small feat, but one I am very eager to achieve. I know I can cross that hurdle, too.

Yes, I am still alive. With the end of the year and the end of a semester at school there was too much going on to sit down and write something properly. But if you have followed the blog on my website you know I have been a bit busy with the hobby after all. The itch has to be scratched somehow.

Chinese New Year is upon us, which means a lot of festivities here in Asia. Expect some more activity on the bands from China and Taiwan as this is the only time of the year that people get some longer time off from work. The coming year is the year of the Dragon and I live in Longtan (meaning Dragon Lake) so my new QSL card will have to be based on a dragon as well. Stay tuned.

After a busy half year it was time to relax a bit and so we went to the southern tip of Taiwan last week. Temperatures were such that the kids could play on the beach and me and my wife could lounge on deck chairs. I didn’t take a radio with me, but still had an interesting encounter with amateur radio.

In the taxi to the National Museum of Marine Biology and Aquarium I noticed the driver had a 2m/70cm rig in his dashboard. So I asked him for his call sign. Instead he gave me his on-air handle. So I asked him again, explaining that when he applied for a licence he got himself a call sign beginning with BM (which is the prefix for the third or entry class station licence). He didn’t remember, because it was over ten years ago that he took the exam and why use a call sign anyway, everybody knew him by his handle? He only uses his rig to communicate with other drivers to warn where the police has put up speeding and alcohol checks.

And that, ladies and gentlemen, is how amateur radio works in Taiwan. Or as I saw it on a Taiwanese forum: “The third class licence is simply to legalize the ‘sausages‘ out there.” CB radio, but with a licence. Happy Chinese New Year to you all!

So with my PSU fixed I thought I would try my luck in the ARRL 10-meter contest. I have never participated in a contest before, but with 10 meters so hot nowadays I’d thought I’d give it a try. Murphy reared its head, so with the wife and kids all sick there was lots of housework to do and too little time behind the set. But I did sneak in an hour or four over two days. My goal: to practise my CW skills. My thought was that doing many short exchanges would give me enough practice to get a little more fluent with the key. So I started out on Saturday morning answering CQs, but nobody came back to me. Fiddled with my side tone, checked my signal with another receiver, no problems found. After four tries I gave up and went up to the SSB portion. Great fun: one Brazilian after another and my first Argentinian on 10 meters. Great to have the comfort of 100 Watts – makes life a lot easier.

Sunday morning the sunspots were lower, but I did manage a couple of State side stations. But it irked me that I hadn’t logged one CW QSO, so I tried again in the afternoon. Found a strong enough signal from Japan and after the second try it worked. Europe was okay and I did log one Dutch station: PI4TUE, the station of the University of Eindhoven, very close to my place of birth.

I had to stop there, but when I came back I switched to SSB again. Worked some Europeans and then, all of a sudden, CX2DDP. via long path. These kind of QSOs are fun though short and I guess Hector Rubens was as surprised as I was. After 75 QSOs I called it a day, which that was right when the band was closing. I’m not in for the numbers, so I am already happy with so many QSOs. I worked 32 different entities in SSB and six in CW, so a grant total of 38 multiplier points. Indeed, no contest for die-hard contesting hams and I doubt that I will often enter other contests.

But the best thing about this contest was that I got my private language student to do a QSO. He is a 16 year old, very shy boy, whom I teach English on Saturday afternoons. He just graduated from high school and he now goes to polytech, which give us a common interest: electronics. Every week I show him some radio related stuff, so this week it was how a QSO is being done. After showing him the ropes and teaching him the NATO alphabet I let him answer CQs with my call sign. He soon found out that you have to open your mouth and speak slowly, clearly and – when using SSB – loudly. Unfortunately these are traits that most Asians don’t possess. But he found it very “cool” that you could call all the way to Europe so he made an effort and in the end he managed a QSO on his own with JA7BEW. He will soon know more about electronics than I, so the exam for a radio licence will be a piece of cake then. Another ham in the making. Who says contests have no use?

Well, this time it was more luck than anything else. Let me explain.

I promised a while back that I would tell you about me enjoying the newly repaired TS-440S. I do enjoy it, that’s not the problem, but the amount of enjoyment is short. How come? My power supply consist of two 7 Ah SLA batteries, which I charge with a wall-wart. With a 100 Watts output I can operate for an hour and that’s it. Even in listening mode it’s not more than a few hours longer as the set draws quite a current. When the batteries go flat it takes some 18 hours to charge them again, so I have to plan my activity very well.

So meet Mr. Jack Huang, a.k.a. BU2BA.

He is living down the street from my mother-in-law, on the edge of Banqiao. He is quite an active ham and so it was obvious that I paid him a visit when I first arrived here a year ago. He has a room full of transceivers and a small dipole on the roof of his 15 storey apartment building, so he is limited to daytime operation due to noise. It’s always nice to chat with him and he is much more technical than I ever will be.

I had to sell off all my 220 Volt power supplies before we moved here, because Taiwan has 110 Volt coming out of the wall sockets. Jack had an old 30 ampere PSU lying around which he sold me together with a Yaesu FT-690mkII for a good price. It is a locally made PSU, so no circuit description, modded with a fan and – to be honest – some shoddy soldering. It worked fine until I started to have problems with RF feedback. Over the course of a few months it became worse and worse until I couldn’t even draw 1 Amp of current out of it. With my modest test equipment and knowledge I measured everything I could: all normal. I put in some new transistors and an IC in the voltage regulating circuit, just in case. Learned a lot about PSU’s in the process, but I still couldn’t find the cause. I even made a video of it.

Back to Jack with the 10 pounds of heavy metal. With his sophisticated equipment he tested the whole thing: couldn’t find anything wrong, either. Then he hooked up a 50000 uF capacitor instead of the 2×10000 uF which were in the PSU and waddayaknow? It worked! Out with the old, in with the new. You guessed it: still the same problem.

I am not a technician by nature. I approach everything with logic, curiosity, trial-and-error and by eliminating the impossible. And then there is my gut feeling which said: “it’s the voltage regulator, sonny!” So with the PSU gutted on my bench I noticed this trimming potentiometer on the voltage regulator controlling pin 2 of the CA723CE IC. Time for a dose of curiosity: what does it do if I turn it? Well, it creaked and squeaked a bit and all of a sudden the PSU came back to life. I hooked up a halogen lamp and no problem drawing 2 amps. I hooked up my TS-130v and no problem drawing 4 amps. I would have hooked up my TS-440S, but the kids called for dinner and Sinterklaas was also scheduled to pay us a visit that night (he never forgets Dutch ex-pats, because he is a really nice Saint), so I left it there.

I later took out the potentiometer and couldn’t measure a steady resistance at any point. I guess it is a 20 MOhm one, but I only had a 1 MOhm at hand. That one did the job too, so I was right in time for the ARRL 10 meter contest. All’s well that ends well. So, am I great or am I just lucky?

Did you read about W2LJ’s rookie mistake? Want to read about another one? Had some afternoon time yesterday and fired up my TS-440S with a fresh battery. Yes, full 100 Watt output this time.

I had no laptop, so I decided to do some just plain old CW/SSB again. 21 MHz was open to southern Europe, so I logged EA6UN in CW. He was quite strong, but some Japanese on the same frequency kept calling him even though he clearly stated “BX2?”. He still got me in the end, though, and I got him. The next nice QSO was CX2TQ in SSB on 14 MHz. Weak but readable when the local QRM was gone. First time CX in the log, so that was nice.

A little later I turned to 18 MHz and CT3FT came in very nicely in CW. I totally forgot to tune up and set the beat tone first and in my enthusiasm I answered him right away. When I looked at my SWR Meter I realised my mistake and started to fiddle with my antenna tuner. No need: he came back to me right away and gave me a 559 report. SWR on my side 1:5, output from my rig 12 Watts, reflected power 7 Watts. Does that mean I worked the Madeira Islands using QRP power? (12-7=5 Watts). Never mind, because I scored three new entities in one afternoon! Not bad at all for a cold and rainy afternoon.