Thursday, April 30, 2009

A burst of propagation

I see from the WebProp display on my website that the sunspot number is 15 today. It hasn't been that high for a while. I don't know if that had anything to do with it, but as I came into the shack to close the receiver and computer down, I notice that I had logged reception of VK2GWH on 20m PSK31 at 21:22utc. In case it was a false spot, I checked the PSK Propagation Reporter site and noted that the same station had been logged at the same time by EC7ABH in southern Spain and four stations in the USA as well. No trace of him now on the waterfall, though!

I'm finding this PSK propagation monitoring quite fascinating as without it, fleeting moments of DX reception would probably pass unnoticed. I guess it was long path, though VOAProp would not have predicted it. It just goes to show that propagation still exists, if you are patient and search for it, and that computer prediction programs don't understand the half of it. I'm wondering if all the grumbling about conditions has more to do with the fact that we're all too used to having instant gratification, of pushing a button and have something happen, instead of having to wait for and work for those DX contacts.

Monday, April 27, 2009

Google's in morse this morning

The front page of Google is displaying the name "Google" in morse this morning.
Does anyone know why? And is it coming up like this for everyone, or only for those that visit a lot of ham radio related websites? I imagine seeing the above might be rather baffling for ordinary users who have never even heard of morse code.

Clean bill of health

I'm glad to say that Dr. Web gave my shack PC a clean bill of health after the scare over the JUMA web server virus attack. Hopefully everyone else who visited the site also avoided infection.

Sunday, April 26, 2009

JUMA server virus alert

I just received an email from the webmaster of the JUMA website, informing me that their web server had been hacked some time on Monday 20th April and some files had been infected by a virus.

To say that I was displeased was an understatement. Most of the computers in our house run Linux, precisely for the avoidance of such troubles. But the shack PC runs Windows - after a determined attempt to use Linux - because Windows has so much better options for ham radio and related software. What's more, I don't run any anti-virus software on it, because it's not a very powerful computer and anti-virus software slows it down far too much. I never visit any of the usual disreputable sites, go in for file sharing or download illegal software, so I consider I'm pretty unlikely to get any malware.

I was also displeased because I have mentioned JUMA quite a bit in my blog during the last few days, with the result that many people will have visited the website, and possibly got infected, just because of me. Thanks, guys.

In order to see whether my computer had been infected, I thought I would try to install and run an on-demand virus scanner - one that would just sweep the hard drive and check everything once only, rather than one that sits eating up memory and CPU cycles all day long every day. But on-demand virus scanners are like hen's teeth these days.

First, I tried BitDefender Free. I was a bit unhappy that it required my email address in order to get a download link. It took ages to install, ran like a slug, and required me to create an account giving loads of details before it would update itself with the latest virus definitions. So I deleted it without even getting as far as scanning my hard drive.

Now I have downloaded, and am currently running, Dr. Web CureIt!, a free utility from the well-known (but not quite as well-known as Kaspersky) Russian anti-virus company. It's running at the moment, using very little memory and making no significant difference to the computer's performance at all. If it finds anything, I'll let you know.

G to K6 on 25W

A lot of people are spending a lot of time online complaining about poor HF propagation at the moment. Sure, the bands have certainly been better. But rumours of the death of the ionosphere have been greatly exaggerated.

Yesterday, after putting out a few calls and making a few PSK31 contacts on 20m, I was surprised to find on PSK Propagation Reporter that my signal had been spotted in California. I was even more surprised to find that it had been spotted by the station of Leigh, WA5ZNU. Leigh is a fellow Elecraft K2 owner and also a member of the Fldigi development team, with whom I have exchanged emails in the past. It was so unexpected that my signal made it all the way to the US left coast I wondered if my spot was actually down to some testing Leigh was doing on Fldigi rather than real propagation. VOAProp certainly didn't think propagation to California was possible with my modest set-up.

However, around the same time this afternoon I was calling CQ on PSK31 again and was answered by Dave, KJ6P, also in California. His print was a bit corrupted although his trace on the waterfall was clear - I sent him 599 because my reactions weren't quick enough to change the report in the box after he called me, but a 479 might have been more appropriate. Nevertheless it seems that my signals really are making it over to W6 land.

Bear in mind, I'm using a dipole in the attic of my house, and the K3 was loafing along at a mere 25 watts output. No HF propagation? I don't think so.

Saturday, April 25, 2009

Getting spotted

I was searching to see if there was a forum for users of PSK Propagation Reporter. There isn't, but I did come across a nugget of useful information that I thought was worth passing on.

The Propagation Reporter spotter algorithm searches for the string "DE CALL CALL" in a transmission to identify a potential spot. In other words, it looks for "DE" followed by the call sent twice. This is a pretty good strategy to avoid getting corrupted calls - it is unlikely that a call will be identically corrupted twice in succession.

Predictably, on where I saw a discussion about this, there were objections to having to conform to this requirement. Frankly, I think the objectors completely missed the point. Participating in PSK Propagation Reporter is entirely voluntary. If you want your calls to be spotted, send them in the form the software looks for. If you don't, they won't be. It's your choice. Simple as that.

Personally I think it's a good idea to send the call after the "DE" at least twice, to help the human operator at the other end know that he has it correctly. I've been sending two 3x3 CQs, i.e. "CQ CQ CQ DE G4ILO G4ILO G4ILO." I think I'll change that to three 2x2 CQs, which will enhance my chances of being spotted. And I'll ensure my call is sent twice when replying to a station, so that I can be spotted when answering someone else's call as well.

Oh, hum

Yesterday evening I left the Juma TRX2 connected up to my MFJ magnetic loop logging PSK31 spots to Propagation Reporter. This morning I switched to 20m and re-tuned the loop to 14.070MHz and saw some clear vertical lines at 100Hz intervals on the waterfall.

My first thought was "mains hum". I am not using transformer-isolated audio connections from the radio to the computer, though the truth is, I never have done so in 10 years of data modes operation, and the only time I did use an isolated interface it actually caused hum due to the laptop computer "floating", having no ground connection through its power supply.

I de-tuned the loop so I could see the hum lines more clearly and was surprised to find that they reduced in intensity along with the signal. They were definitely audio-derived, though. When I moved the Juma VFO the PSK signal traces snaked about but the thin hum lines stayed put.

I hadn't noticed these hum lines on 30m. It appears that they peak up when the magnetic loop is tuned to 20m. But only on the Juma. When I connect the loop to my Elecraft K3, these lines are not present. And when I connect the multiband dipole to the Juma, they are not present either. So the MFJ loop is somehow picking up strong mains hum when tuned to 20m.

I tried grounding the Juma (which doesn't have a ground terminal) but it didn't make any difference. So I'm somewhat stumped at the moment. I know the Juma TRX2 is a direct conversion receiver. And I vaguely recall reading that direct conversion receivers can suffer from hum problems. But I don't know any more than that. Finding out why is one more item to go on my frighteningly long ham radio "to do" list.

Friday, April 24, 2009

PSK Propagation Reporter

Visitors to my site and regular readers of my blog will know of my interest in propagation reporting. I find it endlessly fascinating to see how the ionosphere and other propagation mechanisms manage to convey weak radio signals huge distances.

Last year I became interested in WSPR (Weak Signal Propagation Reporter.) However, I found that I turned on the rig to send and receive propagation spots less and less often. So much of the activity was focussed on 30m that I found it was telling me nothing of interest, so I couldn't be bothered to switch everything on when I had no other use for the radio. When I was using the radio it wasn't free for WSPR, so no WSPR spotting was possible anyway.

A couple of days ago I came across a system similar to WSPR that used spots of regular PSK transmissions, PSK Reporter. Actually, I think I first found it several months ago. At the time, it didn't seem to show much activity and I dismissed it as an interesting idea that was not very useful because no popular applications supported sending spots. Since then, Simon Brown has added spotting support to his Ham Radio Deluxe / DM780 suite, and Dave Freese has added it to his excellent Fldigi. The result is that there is now often around 100 stations sending in spots from round the world, making the site a very good indicator of propagation and who's currently active on digimodes.

What I like about PSK Reporter compared to WSPR is that the reports are of actual stations heard or worked using a real digital communication mode like PSK31, which means that the stations logged are stations you could actually have contacted. But what is really great about it is that submitting reports is done in the background by the digimode software, so using it doesn't prevent you from getting on the air and making contacts.

I also think that the PSK Reporter site is probably the best example of an application using Google Maps I have ever seen. The site itself isn't very fancy but the ease with which you can see what other people are hearing just by clicking on the markers within the application is very impressive. And it looks so beautiful I wouldn't mind having it up on the TV in the living room so I could watch what was happening on the bands even while relaxing by the fire with a glass of wine - though the XYL might not be so enthusiastic!

PSK Reporter is so much more useful and easy to participate in that I think I'll be contributing spots much more regularly, even when I'm not otherwise using the radio. In fact, I'm already using a script by N9MXQ that Google found for me in the HRD forum to display the most recent PSK stations heard at G4ILO on a web page.

Tuesday, April 21, 2009

Ham Banner Exchange is back!

As you may have noticed by the banner at the foot of these pages, the Ham Radio Banner Exchange is back. This is thanks to the expenditure of a lot of time, effort and even hard cash by Fred, WB4AEJ.

As I reported back at the beginning of March, the original Ham Radio Banner Exchange operated by G6DPP stopped working, presumably because the web hosting bill hadn't been paid. Fred contacted me a while after that to see what we could do. We had both attempted to find out the whereabouts of G6DPP, but could not find a complete name or address anywhere on the web. He appeared to be from Loughborough, so I contacted the Loughborough amateur radio club. No-one there appeared to know him, though someone thought they had an idea where he lived, and even drove down that street but found the house they thought was his QTH up for sale. With no way to contact G6DPP there was no hope of simply taking over his existing site.

At this point Fred decided to start from scratch with a brand new banner exchange. He tried using some open source software, but that wasn't much good, so in the end he forked over $45 of his own money to buy a commercial banner exchange script. You can see the result at Ham Banner Exchange.

I think you'll agree that it's very professional looking. What it is not is intuitive to use. This isn't Fred's fault. The principal users of a script like this would be advertising professionals who understand terms like campaign and impression. So far, Fred hasn't found a way to add a step-by-step help page into his turnkey site. But I expect he'll crack it soon.

First, you need to create an account at the banner exchange site. You'll then receive a credit of 5000 impressions - number of times that your banners will be displayed. Note, I wrote banners, plural. If you have more than one ham radio site, you can create campaigns for each of them under your one account. This is an improvement over the old banner exchange which required me to create an account using a fictitious callsign to run banners for my Ham Directory site.

Next, you must "Add New Campaign." This basically means uploading a 468 x 60 pixel GIF banner advert and then filling in a few other details of your site. Creating the banner itself is the hard part, which probably puts most people off bothering, but there are a number of free online banner makers you can use (just type "online banner maker" into Google) or you could try the 7 day free trial of Easy Web Graphics.

After that (and this is the bit that is not obvious) you need to "Manage Impressions" and transfer some or all of the free impressions you were given to the campaign you just created.

Finally, go to "My Campaigns" and click on "Get Code". This will give you a bit of HTML code that you need to copy and then paste into your own web pages. This code will display the banners of other Banner Exchange participants on your pages. Each click on one of those banners will earn you two more impressions to add to those you started off with, so your banners will keep on appearing after your initial credit has run out.

Please make Fred's work worthwhile and join the Ham Banner Exchange. It's a good way to get new visitors to your ham radio website, and a fun way to find out about other ham websites as well.

KComm does JUMA

I have just finished adding support for the JUMA TRX2 transceiver to my logging program KComm. This will be available in the next version, 1.6, which will probably be released in the next couple of weeks. It really needs more testing to be sure everything is working as it should, as there are always issues that aren't immediately noticeable or problems that only occur when you do something you don't do very often.

I ordered a new USB to serial port adapter at the weekend after I experienced problems communicating with the JUMA using the ones I had. The new adapter arrived today. This one uses the FTDI chipset, rather than the Prolific chipset used by the other two adapters. I can report that this adapter works perfectly with the JUMA and both KComm and Fldigi. Unfortunately I notice a slight increase in noise in the JUMA receiver when the computer is connected to the radio using this adapter. I didn't check for this when using the other adapter or the real serial port, so I'm not sure at this point if it is an issue with this particular adapter or not.

Darned computers, sometimes I think they are really more trouble than they are worth!

Monday, April 20, 2009

Power line petition a waste of time

The UKQRM Save Shortwave petition which asked the Prime Minister of the UK to immediately ban powerline network adapters of the type currently being used by the UK's biggest telecoms provider has predictably met with an official brush-off. You can read the petition, and the official response, here.

I initially refused to sign the petition, which earned me a lot of sniffy emails (pun intended) from some people who thought I was a traitor to the cause and deserved to suffer QRM. But I really didn't expect that officialdom would take any notice of a campaign that was amateur in every sense of the word, and whose home page was "". An amateur campaign could all too easily get us dismissed as a bunch of cranks, which would do our case no good at all. In the end, I did sign, since I didn't think it would do any harm, which is why I received an email informing me of the outcome today.

If there is any hope of getting any action at all on this serious issue, it will be achieved through professional legal and technical representation which our national society, the RSGB, can and is doing. That's what I believed at the time, and that is what I still believe.

Sunday, April 19, 2009

Lots of WOTA activity today

It has been a glorious day here in Cumbria, the English Lake District, and lots of amateur radio enthusiasts have been out making contacts fron the tops of the Wainwright fells, taking part in the Wainwrights On The Air scheme.

To my knowledge, we had Rick M0RCP and Tom M3OOL who completed a walk taking in five WOTAs - Grisedale Pike, Hopegill Head, Grasmoor, Eel Crag and Sail. There was also another Rick, G0VMW, who was on Skiddaw and the lesser summit of Skiddaw Little Man.

Due to a back injury I have unfortunately been unable to take advantage of any of this spell of nice weather by getting out on the fells myself. I was happy to catch the first few activations from the home station here in Cockermouth, but the arrival of friends for a barbecue put paid to any hopes of being on the radio when the later ones were reached. There's always another day!

Whenever I try to visit Jeff, KE9V's blog, either direct or through a link from one of the feeds, all I get is a page containing a one line title "". Is it just me?

Friday, April 17, 2009

Hurt feelings

I have received an email from Lee, M0LMP, complaining about my post "More bad manners." Lee accuses me of showing "contempt and disdain" for the Adventure Radio Forum, and of "having a pop" at a group of people who have done "everything possible" to help me launch the Wainwrights On The Air Scheme.

I wish to place on record that I have no argument at all with the Adventure Radio Forum. Through that forum I was able to have much useful discussion that helped me to formulate the WOTA scheme. I felt, and still do, that WOTA is part of "adventure radio" and that it is a legitimate topic of discussion in the forum.

What I objected to was the setting up, without prior permission or consultation, of a set of bulletin boards specifically for WOTA that mirrored those I had already created on the WOTA site. I felt that this would confuse WOTA participants, and feared that the reason for creating them without asking me first was an attempt to steal the discussion traffic from my WOTA site.

I am happy that the person who created them removed them as soon as I had made him aware of my opinion, and I have no ongoing argument with that individual. I am also willing to accept that, however it may have seemed at the time, there was really no ulterior motive for setting up those discussion boards on the AW site. Unfortunately, Lee offered no apology on behalf of his team member while dragging this week-old topic up. Instead, he chose to excuse him for being "new and inexperienced" and then request that I remove the "More bad manners" post.

Given that a major topic of discussion on the Adventure Radio Forum is criticism of the Summits On The Air management team for taking decisions without consulting the members, I find it more than a little ironic that Lee wants to stir up an argument over a matter that only occurred in the first place because one of his team members similarly acted without consultation.

Unfortunately, I find that Lee's email is as lacking in diplomacy as his team member initially was in setting up the boards without asking for permission in the first place, so I will not be agreeing to his request to remove my post. If that means that WOTA can no longer be part of Adventure Radio, so be it.

Serial killer

USB killed the serial port. Unfortunately it has not left us with a satisfactory replacement for communicating with radios. USB to serial adapters just don't work, plain and simple.

I have just finished developing a RigCat rig control file for the Juma TRX2 and Fldigi. If you should happen to want it, you can download it from here. (You'll probably have to right-click the link and do a Save As... or your browser will try to read it.) The file requires the TRX2 firmware version 1.06 which is unreleased as of this moment.

As with anything to do with computers, this was much harder to accomplish than you would imagine. The reason being that communication between Fldigi and the TRX2 was not working properly.

Now remember, this was a serial connection that I had used to successfully update the firmware in the radio three times, so I had reasonable expectations of it working. I had an inkling that there could be a problem when I couldn't use HyperTerminal to send commands to the radio manually. However, another terminal program, RealTerm, communicated with it just fine - although it did report that there were "UART framing errors", whatever they are. RealTerm, incidentally, is a much better tool for debugging serial communications problems than HyperTerminal.

Fldigi has a debugging mode that can be useful when problems like this occur. You just run it from a command line and add the switch "--debug-level 9". On closing a status log will be written to its data file in \Documents and Settings\user\fldigi.files. Unfortunately this file doesn't have standard newline characters so it is hard to read in Notepad. I used a programmer's editor. From this I could see that what was coming back from the TRX2 was not what was expected, and not what I was getting back when RealTerm was used either.

In the end I had no alternative but to disconnect my K3 from my one real serial port in order to try that. Everything then worked perfectly. I stole the sound card interface cables from the K3 as well (which is probably now feeling rather unloved and neglected) plugged them straight into the TRX2 and made a couple of PSK31 contacts into Russia using 4 watts output. Hurrah!

So there you have it. It's now possible to use the Juma TRX2 with Fldigi. As long as your computer has a real serial port. I don't know how to make this work if you have a laptop.

But what I find really interesting is that I have proved pretty conclusively that whether or not a USB to serial adapter works depends on the application. Some will work fine, others will receive garbage. It isn't a very satisfactory state of affairs, and one that's almost guaranteed to result in yet more computer-created frustration.

Blogger b*ggered

I'm experiencing major problems publishing to my blog at the moment. Since yesterday, attempts to publish new posts using FTP are failing with the message that "it is taking longer than expected." In fact, it is not working at all, although I did manage to get my post about the Fldigi update uploaded yesterday evening after a brief change of error message.

It's very frustrating. I'm not the only one suffering from this, judging from the number of complaints in the Blogger Help Group, so it's unlikely to be a problem with my server. It's almost enough to make me switch to having Blogger host the blog, but then all the links to it would be broken.

Fast action from Finland

Yesterday I mentioned that I was trying to create a rig control file to enable Fldigi to work with the Juma TRX2 transceiver. The Juma supports two control protocols. One is a small subset of the Yaesu FT-897 CAT protocol. The other is its own native TRX2 protocol. This provides some capabilities not available when the Yaesu protocol is used, such as the ability to set the receiver filter passband. But I noticed that the Juma protocol did not include a PTT command that could be used by software to put the transceiver into transmit. So any software that used this protocol would have to use the serial RTS or DTR signal for PTT control, and I would have to make up a special interface for it.

I mentioned this last night on the Juma forum, and a reply was posted a couple of hours later. I was not around to reply to it, but by the morning in my inbox was an email containing a new version of the firmware to test. Quick work!

One problem that has me scratching my head is that I can't send commands to the TRX2 manually using Windows HyperTerminal. The terminal displays output from the radio, but the radio does not appear to receive anything I type. I know that communication is working because I have updated the firmware three times now using the same serial cable. So to test the commands I had to use my work laptop which runs Linux.

Thursday, April 16, 2009

Update breaks Fldigi

I thought I'd see if I could get Dave, W1HKJ's excellent data mode software Fldigi talking to my new Juma transceiver and noticed that an update, version 3.11, was released yesterday. Although I didn't even understand any of the changes listed in the release notes, never mind need any of them, I decided to download the new version. Big mistake.

The new version doesn't communicate with my Elecraft K3 at all using RigCat. (HamLib, the much vaunted universal rig communication library, which I guess most Fldigi users use, still doesn't support the K3 at all.)

The first problem is that Fldigi loses the rig configuration settings from the old version, so you have to put them in again. Having done that, the program puts the rig into transmit and that's that. What's more, it completely rogers the K3's communications so it won't communicate properly even when you try another setting unless you turn the transceiver off and then on again. I remember having this headache the first time I tried to get Fldigi working with the K3. I think it's what caused a lot of people to whom I'd recommended Fldigi to give up altogether, because they tried settings that should have worked but didn't because the K3 had gone into a huff.

Unfortunately I didn't discover the trouble with the new version and the K3 until after I had spent a lot of time trying to set up another copy of Fldigi to work with the Juma TRX2. Those attempts were unsuccessful too, but whether that is due to the same reason it won't talk to the K3 or something else is anyone's guess.

Fortunately I had kept a copy of the previous version, 3.10, so I was able to reinstall that and get Fldigi talking to my K3 again. I'll have another go at getting that version to work with the Juma later. I know I should try to find out what is causing the problem with the new version so I can report it to Dave, but life - and my temper - is too short. I just don't have the patience any more to deal with the tiresome propensity of computers to make the simplest of tasks difficult. I just want things to work.

Tuesday, April 14, 2009

New arrival

There's a new arrival in G4ILO's Shack, rather an unexpected one. It's a Juma TRX2 HF SSB/CW transceiver designed by OH2NLT and OH7SV and built by Gerd, DF9TS.

The Juma was a bit of an impulse acquisition. I was surfing the web looking at QRP transceiver kits and happened to come across the Juma website, which I had not heard of before. I was very interested in the TRX2, which seems very good value for money for us here in Europe, better than an Elecraft K2 to which it is broadly comparable. But I was put off building it by the fact that it is an SMT kit. There are a lot of SMT parts to solder!

However, I kept on thinking about the TRX2, and kept on going back to the site, browsing the wealth of information and photos of the transceiver, and reading through the forum. There I came across a posting from Gerd, DF9TS, who was advertising a TRX2A (that's the all-band version) ready built for less than the cost of an unbuilt kit!

To buy one ready built would really be cheating. In any case the post was about three weeks old. I thought that he would probably have sold it, but it wouldn't hurt to enquire. Well, he hadn't sold it, and what's more he offered to send it to me to evaluate on a try before I buy basis. That was an offer I couldn't refuse, and the result was that the transceiver was delivered to me this morning.

I am going to take some time trying it out and comparing it with my various other radios, but here are some initial impressions.
  • The receiver sounds fabulous. There is a sweetness and clarity about the audio that reminds me of the tube based analogue radios of a few decades ago. It sounds even better than the K3, and it seems to hear weak signals just as well as the K3 does, too.
  • There are quite a lot of birdies, many of which are not audible even with an antenna connected. They don't bother me, but some people seem to get very wound up about them.
  • There are only three filters, common for both SSB and CW. They are not as flexible as those in the K3 or most other radios because the low side is fixed at 300Hz. This means that if you want a 400Hz CW filter the high side would be at 700Hz, so the tone frequency would have to be 500Hz.
  • The sound even using the narrowest filter is much easier on the ears (without the harsh, 'ringing' sound) of those in the K3.
  • SSB transmit audio sounds very nice with the speech processor switched out, but a bit gritty and distorted with it switched in. But conditions are poor at the moment and the TRX2 only produces 10W out, so the only SSB contacts I have made so far have needed to have the processor switched in.
  • There is no DATA mode for sound card data operation, and no SSB VOX. Actually, I haven't even figured out how to connect the TRX2 up for data mode operation yet (I'm not sure if there is even a fixed level audio output.)
  • The front panel is minimalistic, there are not many controls, but there is everything you need, making the TRX2 pleasingly easy to use.
  • The connections make rather an excessive use of 3.5mm stereo jacks. The use of one for the front panel mic connector is particularly perverse. But at least they are cheap and do the job.
  • Similar to the Elecraft K2, a lot of the functions of this radio are controlled by firmware. But unlike the K2 the firmware is open source and provided for download. You can compile it using the standard Microchip C compiler. I shall probably be having a go at this later.
I really like what I have found so far. The rig does need some setting up - the S meter is far too generous and the power metering also is a bit optimistic - but this is something I can do once I have finished just playing with it.

Watch this space. I'm sure I'll be writing more about the Juma TRX2.

Monday, April 13, 2009

DC20B addendum

I found a solution to the problem of high sidetone volume in the DCxxB series transceivers. Parallel to R23 on the board there is a space for a resistor labeled R21 which is not used. This runs from the junction of R23 / C27 to ground. You can put a resistor in there to form a potential divider. I used something like a 47K to get it down to a level I was comfortable with. Quite why this is omitted from the kit I have no idea.

However, I also seem to have discovered a bug in the keyer! (Why is it always me that finds the bugs??) I found how to get the memories to replay. You need to key dot or dash on the paddle milliseconds after pressing the function button. The recorded message then replays, but though it sounds fine on the sidetone only the first symbol of each Morse character (or something like that) is actually transmitted. What you hear in the receiver is the odd dit or dah, with long pauses in between!

Chuck, W5USJ, on the dc40kits Yahoo! group, has suggested that to get the rig transmitting and receiving on the QRP frequency I need a 10uH or 15uH inductor in series with the crystal to pull it down a kilohertz. Really, when buying a kit I didn't think I'd need to perform several modifications before the thing would work properly. I don't have any inductors of the right value, it's going to be a challenge to fit one in, and I'm not sure the DC20B is really worth the effort.

DC20B disappointment

I completed the build of the DC20B QRP transceiver yesterday and today, but I am pretty unimpressed with the whole experience. It's true that I am probably hard to please at the moment anyway due to being in a foul mood due to back pain. But even so I doubt if I would think the kit was really worth the money.

The DC20B got off to a bad start due to a part being missing, causing me to have to make a 50 mile round trip to Maplins to remedy the deficiency. After obtaining the missing part I got as far as the initial switch-on stage, but when I tried a key to see if the keyer was working I noticed the first problem which was that the sidetone was at ear-splitting volume. There is no control for setting the level. In fact, the DCxxB transceivers have no volume control at all, which for a direct conversion transceiver with no AGC is probably rather a disadvantage.

This morning I completed the setting up, and found that the transmit frequency, which is supposed to be the 20m QRP frequency, is in fact just above 14.061MHz. What's more, the receive offset, which is supposed to pull the crystal so that someone replying on your frequency can be heard with a tone of 600Hz, moves it more than 1KHz so the received tone is much too high. I managed to solve that by substituting a capacitor in series with the trimmer with a higher value. But I still don't know how to get the rig on to the correct frequency. It drifts a bit, too.

The receiver did peak up after I connected an antenna, but because it is receiving on a little-used frequency I can't tell what the sensitivity is like because I haven't heard anybody. The receiver is certainly a lot quieter than the sidetone!

Despite claims that the DC series transceivers have good immunity to broadcast band breakthrough, the bugbear of direct conversion receivers, I can certainly hear some. Well-known QRPer Richard, G3CWI, built the 30m version and considered it unusable for this reason.

Mounting the board and connectors into the nicely made custom case is a real fiddle, due to the fact that the space has been reduced to a minimum. If the case had been made just a couple of millimetres larger it would have made things a lot easier. I managed to gash my hand whilst trying to force the DC power connector into its hole in the case. There is something odd about this connector too, because the barrel type plugs on the cables that work with the K2 and MFJ Cub are stiff to insert and then make only an intermittent connection.

The keyer is a nice touch, even though I can't get the beacon to work (though the memory is too small to get a useful beacon message into it anyway.) The transmitter is giving me more than 2W out on a 13.8V supply, which is better than spec, and better than the MFJ Cub, though whether that is healthy for the PA transistor which has no heat sink is another matter.

All in all, this is one kit I wish I hadn't bothered to buy, and I suspect it will soon end up in the junk box.

Sunday, April 12, 2009

SOTA Cheaters

There is a bit of discussion going on now among participants in my Wainwrights On The Air (WOTA) scheme. It seems that "chasers" - the participants who sit at home and contact the hill-top portables (activators) for points - are making several contacts with each portable using multiple calls - perhaps an older call of their own plus a couple of club calls they are allowed to use - thus enabling the activator to make the four contacts required for an activation to count just by contacting one station. This practise is apparently widespread among VHF activators taking part in Summits On The Air (SOTA) and so it has been carried over by default into WOTA.

Most people taking part in the discussion feel the ethics of the practise are dubious, but because it has become widely used, and because it reduces the chance that an activation made early in the morning or from a low hilltop with a poor VHF take-off fails to count for activator points, it is accepted. But I wonder if this is really what was intended by whoever made the SOTA rule that activators must make 4 contacts for the activation to count? If contacts with the same person using 4 different calls is acceptable, why not just change the rule to require one valid contact and be done with it?

Friday, April 10, 2009

Missing part

I started assembling the DC20B kit yesterday evening, and continued this morning. But progress has come to a halt as that most frustrating occurrence for kit-builders occurred - a missing part. There are three DIL ICs in the kit, two 8-pin chips and one 16-pin chip, but the socket for the 16-pin chip is missing. So unless I want to solder the IC directly on to the board, which I don't, I can't finish the kit.

The nearest place that sells electronic components is Maplin in Carlisle, 25 miles away. I checked on the web and they have 4 16-pin DIL IC sockets in stock. Hopefully they won't have sold them all by the time I get there, which will be tomorrow, as it will have to be a shopping trip - I'm not driving 50 miles just to buy one 20p part.

Thursday, April 09, 2009

More bad manners

I visited what is now known as the Adventure Radio Forum (AR) today, and noticed that in place of the single discussion board for Wainwrights On The Air (WOTA) there was now a whole set of boards for general discussions, summit alerts, summit news, activation reports, special events and information tips. There is already a set of discussion boards on the WOTA site that cover most of those topics. It looked a bit like an attempted takeover of WOTA after I have done all the work (more than a fortnight's solid effort) in setting up the site.

A couple of hours after I noticed this I received an email from Gerald, G4OIG, who had created these new discussion boards. He expressed the hope that "you will see it for what it is - an opportunity to publicise the scheme on a wider base."

Had I been asked beforehand, I would have expressed the opinion that I thought the existing WOTA discussion board on the AR forum already served that purpose. The creation of several sub-boards seems to me like unnecessary duplication, likely to cause confusion for active participants as to which forum to post to, or extra work as they post their contributions to both.

Using the Adventure Radio forum for WOTA discussions could have saved me a lot of work if the offer had been made before I set up WOTA's own forums. But although plenty of people on the AR forum knew I was setting up WOTA, no-one volunteered to assist at the time. Now that WOTA is clearly popular, it appears that some people now wish that they had done it themselves, and want to muscle in. Perhaps that wasn't the intention, but that's how it looks.

This bad feeling could have been avoided with a simple email beforehand asking what I thought of the idea, instead of telling me about it after the event. I'm wondering if we now spend so much time in front of computers we have forgotten the rules of good manners.

Wednesday, April 08, 2009

Some RTTY contacts

I spent some time doing a bit more work on the latest version of KComm. It has been a while since I released a new version. Truth to tell, I have lost nearly all interest in computer programming these days, partly due to the fact that I am getting old and find it rather a struggle. Programming is definitely a young person's game - you need a sharp mind to keep track of what you are doing.

The problem was that KComm has too many different ways that it can use the sound card and send and receive morse and data. It can display a small waterfall in CW mode that allows quick spotting of a station by clicking on a trace. It can also use the PSK Core DLL - under Windows only - to send and receive PSK31 and PSK63. Alternatively it can integrate with Fldigi to send and receive these and other data modes. But it can also use the built-in capability of an Elecraft K3 to transmit and receive PSK31 and RTTY by sending ASCII text over the serial CAT connection - no sound card needed. If you do have a sound card, though, you can display a waterfall in data mode as well to help tuning signals in so the K3 can decode them. Presenting these options so that a user can select what they want, and then implementing them so the right things show up when the various modes are selected, proved a challenge that made my brain crash whenever I started to think of it. But I think I have finally managed it, although it will need a lot more testing before the new version can be made more widely available.

To test my changes I made a few RTTY QSOs using the K3's built-in RTTY modem, and was pleased to make a QSO with VE5UA in Western Canada running just 60W to my attic dipole.

I really haven't used RTTY very much in my radio career to date. It's interesting how much more brief RTTY QSOs are - no laborious exchanges of equipment details, which is quite refreshing. I quite like to know what radio and antenna people are using and how much power they are running, but I can really do without the information on the interface box, the make and model of PC and what operating system it is running, that so many PSK31 users insist on sending.

Beyond the call of duty

Ron Taylor of Cumbria Designs sent me an email this afternoon with a suggestion to cure the frequency shift on transmit of my MFJ Cub, which occasionally causes the X-Lock board to lose lock.

He wrote: " A further thought from looking at the MFJ Cub diagram; the JFET buffer that is used to couple the VFO into the transmit mixer might be pulling the VFO slightly on Tx.

The reasoning is that the J310 has something like 5pF gate to source capacitance. The impedance presented by the NE612 will change when powered up on Tx changing the J310 source loading. The J310 is coupled to the VFO with a 4.7pF capacitor which. Any changes to the J310 loading will have some effect on the VFO frequency via C35 the 4.7pF capacitor. If it pulls the VFO by more than 40Hz, the X-Lock will come out of lock and attempt to lock to the new frequency.

The reactance of the C35pF is very low at the VFO frequency but because of the J310 input impedance it could be made even lower with little or no effect on Tx output power. By reducing C35 the loading effect on the VFO will be reduced and hence the frequency excursions will be reduced. If you can reduce the frequency excursion below 40Hz, the VFO will remain in lock.

If convenient, it might be worth reducing C35 to 2.2F or even lower to 1.5pF to see if this improves matters."

Unfortunately I don't have any such small value capacitors in my parts box, and the smallest value stocked by the local supplier Maplin is 2.7pF, so I can't try Ron's suggestion right now or even in the near future. C35 is an SMT component on a tightly packed board, so any replacement would have to be tiny. But when I can get hold of a suitable part I'll certainly give it a try.

But kudos to Ron for going beyond the normal definition of product support and providing a solution to a flaw in the MFJ Cub design that would enable me to get the full benefit of the X-Lock. On the basis of my experience with this kit I can recommend Cumbria Designs unreservedly.

QRP and a little antenna

One of the nice features of Blogger is that it allows you to subscribe to or "follow" other blogs, so that you can easily see when any of them receive a new posting. I have just added N8ZYA's Radio Blog to my list - whose tag line is "QRP and a little more."

N8ZYA operates using an IC-703 QRP transceiver and an indoor antenna that you can see in the picture at the top of his blog. It looks like a hospital drip stand! I think it is a pair of "Isotron" antennas, a type of limited-space antenna sold in the USA.

Discussions about how well the Isotrons work (or don't) can be a bit controversial. These antennas get a lot of 5 out of 5 reviews at However, many sceptics don't believe they can really work, as they appear to defy all known laws of physics. I'd love to get my hands on one just to try it head to head against my MFJ Magnetic Loop, the only limited space antenna I know of that really does work.

In my opinion, the Isotron only gets 5/5 ratings because anything that isn't a screened dummy load will radiate some RF, and people who have low expectations of what an indoor or stealth antenna can achieve are easily impressed. It would be nice to be proved wrong, though.

Tuesday, April 07, 2009

Truth in advertising

I was searching for a source for BNC plugs for RG-174U cable when I came across this page. I burst out laughing when I saw the product listed at the bottom. Nice to see an honest product description. :)

Small is beautiful

Although I own an Elecraft K3/100, I get much more enjoyment from making QRP contacts. However, for me, QRP isn't just about turning the power down on your store-bought (or even kit-constructed) radio. It's about making contacts with equipment that is small and simple.

There is something that is just magic about making contact with someone thousands of miles away using a radio small enough to hold in your hand. That's one of the reasons why I've been working on the MFJ Cub recently, and why I ordered a DC20B kit to add to my QRP radio collection.

I decided that the tiny MFJ Cub deserved a tiny Morse key to go with it, so I ordered one of the Christmas keys from Morse Express. You can see the miniature 20m CW station in the photo, next to a copy of SPRAT (the G-QRP Club magazine) which is A5 size, for comparison.

The first contact made with this combo was with George, KZ1H, near Boston MA. Across the pond with just over 1W to an attic dipole using a radio you can hold in your hand. Anyone who says that life's too short for QRP, or that you need an outside antenna to make contacts on HF, doesn't know what they are talking about.

DC20B arrives

A tiny box arrived in the post this morning, containing the DC20B kit from Hendricks QRP Kits. It has taken nearly 4 weeks from placing the order. It's a long time to wait, but this is an acceptable price to pay for the much lower shipping cost. It also arrived stamped "Customs cleared" with no VAT to pay - another major saving.

I'll probably put it on the shelf for now, as I have a couple of other radio projects that still need finishing off. But I'm looking forward to building it.

Monday, April 06, 2009

Cub tamed - just about

Over the weekend I spent most of my time installing the Cumbria Designs X-Lock board into the MFJ Cub and getting it to work.

The first problem was deciding how to interface the board to the Cub. The instructions say that the VFO output should be sampled at a point that is buffered and provides at least 500mV of signal. I decided to take the signal from either side of R19 (marked in blue on the circuit), which also provided a convenient point for attaching the miniature co-ax. Because there was not a lot of space for mounting the varicap compensation components, I decided to try connecting the VAR output via a single 100K resistor to the existing tuning varicap, shown by the red arrow.

The initial lash-up seemed to work. The Cub no longer drifted. The other noticeable effect was that the tuning range was reduced. Instead of tuning from about 14.003 to 14.063, it now tuned from 14.043 to 14.063, a range of 20KHz instead of 60KHz.

I had sent a copy of the circuit with my proposed connection points to Ron, the X-Lock's designer, and he confirmed that connecting the control voltage in the way I proposed would result in a reduced tuning range. He recommended installing the compensation varicap (actually a red LED) supplied with the kit, connected via a very small fixed capacitor - 10pF or less - to the main varicap, to restore the full tuning range. However, 60KHz of tuning range in a single turn of a potentiometer always made the Cub tuning a bit tricky, especially as the tuning is somewhat non-linear with most of the bottom end being covered by less than a quarter turn of the knob. Most of the QRP and slower CW activity takes place in the top 20KHz of the CW segment so the reduced tuning range and greater linearity is actually an improvement. I decided to leave it as it is for now.

Installing the X-Lock board into the MFJ Cub was the next job, and one of the hardest parts of the task. In the end, my XYL gave me an idea. I attached it using double-sided sticky pads to two of the push-on connectors, which held the board upside down at the top of the case, as shown in the picture below.

Initially I decided not to install the LED that shows the X-Lock status. This would save a few milliamps and avoid the need to drill the case. But after I had closed up the Cub and tried a test transmission I found that it was still drifting so I had to take it all apart again. I removed the Cub circuit board from the case, removed the existing miniature red power LED and enlarged the hole it occupied to take the standard size status LED provided with the X-Lock. This now functions as a dual purpose power and VFO lock indication, so I can see if stabilization has been lost.

I found that the X-Lock would tend to lose lock either on key up or key down. This happened very often when the Cub was on the 13.8V main shack supply and producing about 1.5W. The problem could be almost eliminated by reducing the power to 1W or slightly below or by reducing the supply voltage to 12V. Curiously enough, loss of lock did not occur when powering the Cub from a ten-cell NiMH battery pack.

Ron at Cumbria Designs thought that the Cub power supply lines were a bit light on decoupling, and that voltage transients could be causing the VFO to "chirp" slightly on key down. He made a couple of suggestions to try and solve the problem, including installing some larger electrolytic capacitors on the supply rail. I should say at this point that the support provided for the X-Lock module is absolutely first class. Anyone thinking of using this board to stabilize a VFO in their own transceiver should have no qualms about it. You are not "on your own" once you've built it.

Ron's suggestions didn't solve the problem. The Cub VFO doesn't chirp, it actually shifts frequently slightly between key up and key down. The X-Lock sometimes thinks this is an intended frequency change and relinquishes lock for a couple of seconds, allowing the VFO to drift. This is not the fault of the X-Lock board.

On TX the VFO shifts the opposite way to if the supply voltage sags a bit. I don't have a frequency counter, but the shift can be heard in another receiver just by placing a coupling antenna near the Cub and tuning to the VFO frequency. I have not managed to establish why the Cub VFO shifts frequency in this way. However, as already mentioned, this frequency shift can be minimized by reducing the power or using a different power supply. This allows the X-Lock to keep control of the VFO.

I think my MFJ Cub is now as stable as it is going to get.

Friday, April 03, 2009

Cumbria Designs X-Lock

The X-Lock VFO Stabilizer kit that I ordered from Cumbria Designs arrived today. It is a Huff and Puff frequency stabilizer that is intended to be used to give long term frequency stability to older radios with non-synthesized radios, and it has been used with transceivers such as a TS-520. I hope to use it to cure the drift in my MFJ Cub.

As you can see from the picture above, it's a pretty small board, though it is about as tightly packed with components as it is possible to be. The X-Lock uses conventional leaded through-hold components, so no special skills are required for construction. Some of the solder pads are pretty small, but the board is high quality and well screened and I found no tendency to create solder bridges. It took a good two hours to fully populate the board.

Plug in connectors are provided for all external connections, which is very convenient. Besides power, you will need a buffered feed from the VFO to be stabilized at a level of 500mV or more, and you will need to connect a compensation varicap into the VFO tuning circuit. I'm hoping to use the existing varicap in the MFJ Cub, but some experimentation may be called for. There is also a tri-colour LED that is used to indicate status.

The board worked the first time it was powered up, with the LED flashing as described in the manual. I then applied some RF using my AA-200 antenna analyzer as the source. The LED indicated that the stabilizer had lock. When I changed the frequency of the antenna analyzer signal, the X-Lock unlocked to allow the frequency to be changed, then locked again a couple of seconds after the frequency was steady.

These days I find circuit construction hard on the eyes, and on the back due to bending over the desk for two or three hours, so I am quite tired after building and testing the X-Lock. Trying it out in the MFJ Cub, and installing it permanently if it does the job, will be a task for another day.

Buying from the USA

How can Hendricks QRP Kits charge 15% of the kit price for shipping to DX locations (outside the US) while Elecraft charged me $41.10 for an order valued $109.95? This was the question I asked in my final posting to the Elecraft reflector, the one that generated so many complaints and emails of abuse that I quit the reflector and ceased doing anything else for the Elecraft "community".

One of the complaints was that such issues have no place on a "technical" reflector. Not true. The Elecraft reflector has never been solely for technical matters - the Elecraft principals themselves have stated that anything related to Elecraft products is a fair subject for discussion. More likely the offence was caused by the fact that the question was seen as yet another criticism of Elecraft. But it is still a fair question, and one of interest to anyone outside the USA, and in the UK particularly, who wishes to buy Elecraft products, since they can only be purchased direct from Elecraft.

One US ham who felt my question deserved a fair response was Bob Naumann, W5OV, who happens to have a lot of experience of sending products from the USA to Europe. He told me that the maximum charge for sending a 1lb package by USPS Priority Mail should have been $30.80, so Elecraft is adding quite a bit to the shipping cost it charges to customers. The amount they actually paid the USPS was $25.18, which Bob informed me is what the post office would charge without insurance, if they processed it online without taking the package to the post office.

Given that I was told the reason for using USPS Priority Mail in the first place is that cheaper methods don't provide adequate insurance, this seems a bit disingenuous. Perhaps Elecraft is bearing the risk itself. It is also entitled to charge for packaging and paperwork. Still, when the charges amount to 40% of the order cost it is enough to put you off ordering anything else from the USA, especially when the costs of collecting VAT, payable this side of the pond, are also taken into account.

I subsequently ordered a miniature morse key costing $79.95 from Morse Express. This package also has a shipping weight of 1lb. I was advised to use Express Mail International at a cost of $45.60 because the alternative Air Parcel Post at $39.80 was slower and not trackable. So in this case the shipping amounts to more than 50% of the order value.

I have just received the letter from ParcelForce in the UK demanding payment of the £11.80 VAT on this morse key. The clearance fee for this is £13.50 - more than the cost of the tax. In total I will have paid just over £113 for a product sold in the US for $80!

So how can Hendricks QRP Kits send kits to overseas customers and charge for shipping a mere 15% of the kit price? I'm still waiting for the answer to that, because the DC20B kit that I ordered from them in the middle of March has not been received yet. They certainly will not have used a trackable shipping method, so there is no way of finding out where it is. When it does arrive, I'm told there is a good chance that it will slip under the radar of the customs people so there will be no tax to pay, and no clearance fee either - two major savings, if I'm lucky.

It seems that hams in the UK wanting to buy radio products from companies in the US have two choices - pay high fees for express, trackable insured shipment that guarantees you'll have to pay VAT and a clearance fee as well which can more than double the total cost, or use cheap, uninsured, slow and untrackable surface post and run the risk that the product never arrives at all. I think it's time to give up buying direct from the US. It would make sense for companies such as Elecraft to start selling through a UK dealer.

Wednesday, April 01, 2009

Thwarted - by a bird!

It was a fine day today, so my wife and I decided to go for a walk in Dodd Wood near Keswick. I took the TH-F7E with the aim of making my first activation under my Wainwrights On The Air scheme from Dodd summit.

We had a pleasant stroll round the western and southern flanks of the fell with great views over Bassenthwaite Lake and Keswick. But as the summit came into view a new-looking wooden gate barred the way. On the other side was a wooden hut, a couple of men and a Land Rover.

We spoke to one of the men and he informed us that the Lake District Ospreys had returned from Africa just this morning, and had decided to nest in a tree close to the path. The route had been blocked off to prevent disturbance by members of the public. Because this had only just happened, there were no signs in place to advise walkers not to go that way if they wished to reach the summit. We had a quick look at the birds through the chap's binoculars and then retraced our steps.

We tried another way up to the summit but found that route was barred as well. So we called it a day. There probably is a way up to the top that avoids disturbing the birds but I'll wait for it to be signposted. Our next trip to Dodd will likely be with a tripod and spotting scope!

Don't hams have any manners?

I just returned from a nice walk, in a good mood. That soon ended when I opened my inbox and found the following. Note that this is the entire text of the email:

Subject: VOProp and Saving Settings

Everytime the softyware is started the software defaults to a base setting, I can change the settings to my home QTH and the relevent date, but these all are lost every time I exit the software, How can these be saved, and also is there a way for it to take the date and time from the computer itself?

No greeting, no pleasantries like "Thanks for the nice free software." Not even a "73" at the end or a name to say who the email is from.

No mention of the operating system it was being run under. I can guess it's Vista, since this is a problem I've heard of before and is due to VOAProp not being compatible with Vista. However there is a workaround that was suggested to me by another user which is described at the top of the troubleshooting page. So not only does this amateur have no manners, he expects me to spend my time answering his question even though he couldn't be bothered to spend any of his time reading the documentation.

Is it any wonder that I no longer develop or support my ham radio software?