Saturday, January 30, 2010

Luna

It is a clear but cold (-4C!) night tonight and a full moon is shining. I thought I would try to take a picture of it using my £29 Aldi spotting scope and £25 eBay bargain digital camera. It made a nice change from trying to figure out how to interface my radio to my new computer.

The digiscoping adapter I got from Scopes'n'Skies certainly helped with holding the camera in position and the infra red remote control I managed to get for the camera meant that I could fire the shutter when everything was steady. It's not bad for a first attempt but I'm sure it ought to be possible to get the image a bit sharper.

My camera tripod is really poor and hard to adjust so you have to point past the object and then hope it settles back with it in the centre. This normally takes a few attempts. But the main thing is that focus is quite critical and it's hard to tell when you have got it exactly right using the little screen on the back of the camera.

There was a bit of colour fringing on the original image - purple at the top and green at the bottom. Well I suppose you can't expect perfection with £29 optics. I eliminated it using the simple expedient of getting IrfanView to convert the image to greyscale.

It would probably be more interesting to photograph a partial moon when you could see detail emphasized by shadows along the terminator. So, weather permitting, I hope to try to take some more Moon photos later.

Friday, January 29, 2010

Arrghh, computers!

My new shack computer is here, and I am nowhere near having it usable to get on the air. I have had one problem after another. Some are silly if annoying things, like forgetting to save my Firefox bookmarks before I vaped the hard drive of the old system. But one is a show-stopper. The new PC doesn't seem to have what I recognize as PCI slots.

Things weren't helped by my printer suffering an ink cartridge failure today, the day I sold my VX-8E to someone who paid extra by direct bank transfer in order to have next day shipping to his QTH in Luxembourg. As you probably know if you have sold any gear recently, if you arrange courier shipping online you need a printer in order to print shipping documents with barcode labels to fix to your package. So when the printer came up with "Error - Check right print cartridge" I was not best pleased.

I knew that the colour cartridge was low on ink and had half expected this might happen, so I whizzed down to the local computer shop and bought a replacement. Still the same error. We then realized that the printer was saying the right print cartridge needed checking. That's the black ink one, which I knew having looked at the indicators recently was still at least three quarters full of ink.

We took it out, looked at it, put it back, still no improvement. I Googled the error message, and the suggestions included cleaning the contacts with a cotton bud moistened in water, which didn't help. The other suggestion was that the ink cartridge electronics had failed, so despite Olga's reluctance to replace a thirty quid ink cartridge that was still almost full of ink she agreed to another trip to the computer shop. I think the fact she could see I was close to throwing the printer on the floor and stamping on it may have helped. Sixty quid's worth of ink cartridges later and I was finally able to print the shipping documents, but too late for a pickup today. Grrr.

Meanwhile the new computer arrived. Thankfully it had the Windows XP "downgrade" already installed on it, so I could set straight to work. It has a 300MB hard drive, all partitioned as one C drive (plus a recovery D drive.) I wanted to shrink C and create a separate D drive which I would use to store backups created using MagiCure Professional, which is a kind of super System Restore. But I couldn't find a way to do it.

I thought I'd read that you could resize drives using the Disk Management console in Windows, but I couldn't find a way to do it. My usual tool, GPartEd, crashed with a kernel panic so I couldn't even try that. I had a free Partition Manager program from a 2006 magazine cover disc, but that said "no free space" so it couldn't shrink the drive. I also tried various things from an "Ultimate Boot CD" but they either couldn't handle NTFS partitions or offered to correct scary looking errors with the existing partition that I didn't believe were real errors. So I gave up and will just have to make do with a huge great C drive.

Installing software is a slow process and I had just got to the point where I wanted to start to install the ham radio apps. For this I need my new serial port board and my old sound card, which I'd removed from the old computer. I opened the new one up, and was amazed. It has only one slot that looks like a PCI slot. But actually isn't, when you compare it to the one on my SoundBlaster Live 24 card that I use for digimodes.

There are also three tiny little slots, which fortunately appear to match the one on my newly bought serial port board, so at least I can use that.

So the question now is what do I need to be able to work digimodes with my new computer? I don't think I can use the built in sound card as it has a control panel with sound effects that I can't see any way to turn off. In any case I had thought I would use the built-in sound for normal audio.

If I had known in advance that I couldn't use my old sound card I think I might have saved myself some trouble (and a lot of spaghetti wiring) by getting a RigExpert or similar that combines the sound card and serial control functions into a single serial cable. I'm getting tired (and a bit too old) for crawling around on the floor under the desk groping behind the computer trying to plug audio cables into sound cards by trial and error.

Double arrghh! Having installed the serial board I have now found that I can't connect my radio because the connector on the computer and the connector on the cable are both male! I used a "gender bender" on the old computer which I forgot to disconnect and I have already given it away! So I am completely thwarted and frustrated at the moment, unable to connect my radio to the computer for either digimodes or logging.

I hate messing with computers!

Thursday, January 28, 2010

Frequency unknown

I recently bought a batch of crystals on eBay. They are from early 2m FM crystal controlled transceivers, some are receive crystals and some are transmit crystals. They have the 2m frequency stamped on them, not the actual frequency of the crystal. Because I don't know what radios they were from originally I do not have the remotest idea what their real frequencies are.

I Googled up "crystal test oscillator" and breadboarded the first circuit I found, a Colpitts oscillator, but it didn't appear to work. I tried several crystals but could not detect any oscillation. I tried one of my HF QRP CW crystals and I couldn't receive a signal from that either, so obviously my oscillator was no good. I didn't want to build something permanent as this is probably the only occasion I'll ever need to use it. But I'm a bit stumped as to what to try next.

As I'm going to be tied up for the next couple of days setting up the new shack computer I'll probably put the crystals back in the junk box for now. But I really need to find out what they are as a future project depends on them. I had to buy more crystals than I needed because of the way they were auctioned on eBay, so I want to get rid of the ones I don't need. But I'd prefer to sell them as tested and to be able to tell buyers the frequency.

Any suggestions?

Where do old computers go to die?

I hate getting a new computer. It isn't just that I'm cheap, though that does have something to do with it. It's just the hassle and amount of time it takes to get all your software installed and set up the way you want it again. Although I will copy all my files to a backup drive so I can transfer them to the new one, inevitably I will end up forgetting (and hence losing) something. And equally inevitably I will find that I've lost the license keys for some programs I've bought, or am unable to find to re-download some useful program I acquired years ago.

But I can't put off the inevitable any longer. My shack computer is over five years old. It is an Acer F1, an entry level system when I bought it. And it is just getting way too slow. When I type a web address into Firefox there can be a visible delay between pressing a key and the character appearing. If I do anything in the web browser or open another program while transmitting in digimodes I hear an interruption to the transmitted audio. And when using a mode like JT65 which waits to the end of a transmit period before decoding, the decoded results do not get printed up until the next period has started, making it impossible to reply to a CQ.

Another reason I don't like buying any new computer equipment is fear of getting another QRN generator. Because of this I always stick with big name brands like HP, Dell, Toshiba or Acer. Their products are better quality and generally electrically quieter because they have to meet tough standards set by some of their big corporate customers. They don't design down to a price.

I'm keeping my existing 19in. flat screen monitor. I'd like a larger one but my shack is so small that I don't have the space. The existing one is a bit of a QRN generator on VHF because my 2m antenna is almost directly above it. But any replacement might be even worse.

My new PC was dispatched by Misco within an hour of ordering it. Unlike my old Acer it doesn't have an RS-232 port so I took the opportunity to order a PCI dual port serial card to install inside. It cost just over £20. Now I will have TWO real serial ports to use for radio control. Why more hams don't do this and end up fighting problems with USB adapters I have no idea.

The other thing I made sure of is that my new computer comes with Windows XP. If it isn't already installed then I'm promised a "downgrade disc" from Vista to XP Professional. I have no need for Microsoft's latest bloatware, which apart from needlessly consuming resources on things that I obviously don't need because I'm managing perfectly well without them right now, has compatibility issues with many ham radio programs. I really would rather run Linux, as I do for work, but every time I hear about some new program I'd like to try out (like JT65-HF yesterday) I'd feel I was missing out. So now I should be able to carry on using Windows XP for another five years.

The last reason I hate buying a new computer is finding a way to get rid of the old one. The days when you could leave it out with the garbage and they would take it are long gone. Now you have to pay the council to dispose of it (silly me, I thought that's what my council tax was for!) Charity shops won't take old computers for fear of ending up with someone's porn collection, plus they say there is no demand for old computers anyway.

So any ideas how I get rid of an old PC without having to pay to have it taken away? (See, I said I was cheap!) I'm sure it could still have a useful life running one of the lighter versions of Linux, or even DOS! Any UK ham willing to collect it can have it for free (I think we even still have the original box, manual and Windows XP disc somewhere.)

Overnight DX on JT65A

The haul of JT65A stations heard overnight on 80m was quite impressive, although there is a gap in the middle of the night when the program seemed to stop decoding. I woke up around 4am and went to see what had been heard, and nothing was on the screen since before 2am so I stopped and restarted the program.

The number of different stations logged is far fewer than when I did a similar exercise using PSK31. But the proportion of US stations logged is much higher. The best DX - KE5ZGI in New Mexico, a distance of nearly 8,000km - is much farther than anything I have heard on 80m before. So this JT65A mode is very interesting if you just want to see how far you can get.

I'm receiving on 20m now, and hopefully later on I'll be able to find the time to attempt a few more JT65A contacts.

Wednesday, January 27, 2010

Celestial contacts

Paul, PC4T alerted me to the fact that a new piece of Windows digimode software has just been released: JT65-HF. I downloaded it, installed it, and then spent about two hours trying to figure out why it would not key my Elecraft K3 into transmit. The short answer: it works only with a real serial port, not LP-Bridge nor a virtual serial port.

Having sorted that out I quickly figured out what to do. Since it was by now late evening I tuned to 80m, 3.576MHz, and heard the musical tones of JT65A signals. Both EA3AQS and WD4KPD were calling CQ. I don't think I have ever worked Stateside on 80m, but in my haste and myopia I double-clicked on EA3AQS's CQ and the software immediately began calling the Spanish station. After my call I decoded a report from him, to which I replied with my report. His RRR confirmation followed, and the contact concluded by sending 73. Flushed with success, I responded to PA0BWL who was calling CQ, and another contact quickly followed.

JT65A is one of Joe Taylor K1JT's modes that were developed for meteor scatter work to allow contacts to be made with weaker signals than would be needed using ear-decoded CW. For some reason it has become quite popular on HF, but this new program by another Joe, W6CQZ, is much easier to use than the original WSJT program. Another nice feature of this new program is that it can spot stations heard to the PSKReporter.info website. Originally W6CQZ ran his own reverse beacon site but I think that combining this with the popular PSK Reporter is a much better idea. The screengrab below shows the JT65A stations I'd heard after a couple of hours of operating this evening. Remember, I'm using a shortened multiband dipole crammed into a very small attic, so Eastern USA and Asiatic Russia are DX for me on 80m.

JT65-HF probably won't appeal to a lot of people. Only a signal report and locator are exchanged during a typical six minute QSO, so it is not a chat mode and many will probably consider it rather too much like watching paint dry. But I actually find it a very pleasant, relaxing mode to use. The tinkling tones of the JT65A transmissions sound like a tune being played on a celeste (a musical instrument) which I find very therapeutic.

I don't think I'll be deserting PSK31 for JT65A, but I'll certainly be spending more time with this wonderful addition to the range of digimode software, and I'll be leaving the rig on receive overnight to see what comes on the air while I'm sleeping.

Pimp my radio

Don Rasmussen WB8YQJ has created a "simplified" computer control interface for the Elecraft K3 that resembles a Drake R4C receiver. You click on the various controls to make changes. Currently only the S-meter displays an actual reading, the VFO and other controls are in progress.

I think it's a fun program whose novelty will soon wear off, but it did make me think of an idea that could get even me interested in SDR. What about a board running software that does everything expected of the computer side of a software defined radio? But instead of using a screen, mouse and keyboard for the user interface - though that could be an option - it would have a specially designed bus that would allow you to connect real switches, potentiometers, rotary encoders, meters and digital readouts to control the various different functions and display information.

Think of the possibilities. Instead of using a high-res picture of an R4C for the interface you could build everything into an actual R4C case, or indeed any other old radio that is dead beyond redemption, and create a "classic" radio with state-of-the-art SDR internals. Or you could design your own front panel exactly to your liking and create your own unique radio.

"Pimp my ride" is a TV programme about people who hack and customize cars to create something individual. Why not "pimp my radio?"

Tuesday, January 26, 2010

Stripboard magic

I have completed one of the constructional tasks on my list for this year, which was to make an interface between my Elecraft K3 and my 2m transverter so that I can leave the transverter on and it will only switch to transmit when I am actually on the 2m band. Up until now I have had to switch the transverter off if I change bands, which is not so good for frequency stability.

The circuit I used was given to me by Bill W4ZV on the Elecraft reflector. It combines the KEYOUT PTT control signal with the DIGOUT signal, both available on the K3's ACC socket. DIGOUT can be configured to go low only when a transverter band is selected. I only have one transverter, so that is good enough for me.

The combining is done using a dual opto-coupler TLP627-2. I'm not quite sure why an opto-coupler is needed, but as that is what the circuit said, that is what I used. The reason it took a while to get around to making this interface is that it was some time before I had a big enough list of parts to order from a source that sold the TLP627-2.

I built the circuit on a small piece of Veroboard. Prior to building it I thought I would design the layout using some stripboard layout software. Of course there was no need to use a layout program for such a simple circuit. But I have a more ambitious project in mind that I would like to do on Veroboard and I wanted something simple to try different programs out with.

I tried several programs, including VeeCAD, VeroDes, Stripboard Designer, Stripboard Magic and DIY Layout Creator. All of the programs to a greater or lesser extent suffer from a limited library of components, especially RF components like Toko coils or trimmer capacitors that you tend to use in RF projects. Therefore their usefulness depends a lot on the extent of the shortfall and how easy it is to add new components to the library.

The Java based DIY Layout Creator was quite impressive, and runs on Linux as well as Windows. However, adding components involves creating XML files containing the Javascript to draw the component.

My ageing brain struggles with complex tasks so I was attracted to the idea of programs that could generate a stripboard layout from a circuit diagram, or at least validate that the layout matches the circuit, because I am bound to make a mistake doing it manually. VeeCAD can check a layout using a circuit network description exported from a design program like TinyCAD. It can create a layout automatically but that feature is only available in the paid version so I couldn't test it. VeeCAD's component library is a bit limited and an annoying restriction is that you can't easily change the format of a resistor to mount it on end to save space.

Stripboard Magic is the only other one of the programs I mentioned that can generate a stripboard layout from a circuit. Its circuit designer is built-in and quite easy to use. The automatic layout generator seems a bit quirky, and produces a layout that may be electrically correct but seems to put the components all over the place. However you can add the components one at a time which gives you more control over the placement, and it will then check the layout against the circuit. Adding components doesn't seem too difficult and the library uses bitmaps for images so you could make them look realistic. Stripboard Magic is an old program that was written by a now defunct company but it is the one I like best at the moment.

I'm surprised I didn't find anything better for laying out circuits on Veroboard. I'd be interested to hear what methodology other constructors adopt when building circuits on stripboard.

Broken ring

My website, G4ILO's Shack, is a member of the QRP Amateur Radio Webring run by Thom LaCosta, K3HRN.

Webrings are an idea from the early days of the web before search engines were invented. They provide a way for people to find other sites similar to the one they are looking at. I think webrings are rather outmoded now, a bit like websites developed using frames. But for specialist sites like ours they do still serve a useful purpose and allow people to discover interesting sites they might otherwise miss.

But they only work as long as the ring is maintained. Click the Next link on my site and you'll come first to a ham site with an annoying popup Java ad and then to a page that was once a QRP site informing you that Geocities has now closed.

One link will take you to the G-QRP Club website. However, this site has recently had a makeover and the webmaster clearly decided that he didn't want to spoil his layout by including the QRP Webring banner, creating another dead end.

I'm beginning to wonder whether it is worth staying a member of the webring. It brings a tiny number of visitors to the site compared to Google. I still think it is a nice idea, like the Ham Banner Exchange, but at the moment it's just broken.

Monday, January 25, 2010

Misinformation

John Harper AE5X's blog isn't in my blogroll, partly due to the fact that he declined to publish my comments to a couple of his earlier posts. In fact I see that comments are off for several posts that I might have liked to comment on, suggesting that John isn't interested in anyone's opinions but his own.

In a recent post John has a dig at propagation indicator gadgets including my WebProp, claiming they give indications of conditions that are incorrect. John makes his point using a screenshot of the DX Cluster showing a lot of spots for 12m contacts, together with shots taken at the same time of WebProp and another gadget from Paul Herrman N0NBH claiming conditions on the higher HF bands were "poor".

In defence of WebProp I would say that the 24MHz contacts John saw on the DX Cluster were probably short skip sporadic-E or trans-equatorial propagation, two modes that to the best of my knowledge are completely unpredictable. WebProp and the other propagation gadgets base their estimates solely on the effect of D-layer and F-layer ionization which is affected in a fairly predictable way by the solar flux, A and K indices.

But upon further reflection I realized that John had made a good point. WebProp and co don't come with any warnings or disclaimers that they don't show the whole picture. It may be obvious to some that you can't predict the unpredictable, but there are a lot of people who believe that if a computer says conditions are good or poor then that's what they must be. A propagation indicator that can't reliably show what conditions are actually like is about as much use as a weather forecast that says it's raining when it is sunny (though in the UK we're already used to that.)

With hindsight it would have been better - or at least more accurate - to have made WebProp just present the solar indices received from WWV and NASA and leave their interpretation to the end user. However I can't just withdraw WebProp as a lot of people are now using it on their sites. Nor can I easily remove the suspect information as that would make the box shorter and leave an ugly gap beneath it.

What I have done is add an option "condx=no" that can be used to suppress the band condition indicators, as shown above. This will make the box shorter so anyone who decides to switch to using this version will also need to adjust the height they allowed for the box.

It would be better if the condition indications used the presence of DX Cluster spots for their assessment of band conditions. I have had the idea to do this for a couple of years, but it is easier said than done and it is quite possible that I will never get around to it.

In the meantime, the "condx=no" option should make the information WebProp provides acceptable to those who think propagation gadgets should stick to the facts. Perhaps AE5X might even like to include the new version on his blog site?

Sunday, January 24, 2010

A tale of two websites

Take a look at this website, belonging to the GM DX Group. Now take a look at this one, the website of the Guernsey Amateur Radio Society. Surprisingly similar, aren't they? In fact, if you look at the HTML code that produces these pages, the similarities are more than skin deep. A friend of mine, who is a bit of a stickler for such issues and drew this to my attention, tells me that the Scottish group was the original designer and that they are a bit unhappy about the Guernsey club having ripped off their layout.

There are laws about using other people's material on a website, and some of us hams either don't know the rules or think they don't apply to us. I have had a website for a long time and I have encountered all extremes. On the one hand there are people who ask permission simply to link to an article on a site. That really isn't necessary. I have never met a webmaster who didn't want links to pages on his site as links are what bring visitors, which every site owner wants.

At the other extreme there are people who lift content willy-nilly and put it on their site without asking permission at all. One of the worst offenders right now is an Elecraft K3 owner from Florida who recently started a download site containing copies of equipment manuals and other articles. I'm pretty sure he doesn't have permission to host this material because this same friend of mine found a PDF file containing his review of the Elecraft K3 which had been lifted from his site, along with photos and other material, and his permission had never been asked at all. Indeed, this friend tells me there are even Celine Dion MP3 files on the site. Not only are US copyright laws being flouted but the terms and conditions of his hosting service as well.

I think bloggers sometimes sail a bit close to the wind too. It used to amaze me that some bloggers managed to get a picture of a guy they worked that morning to illustrate their blog, until I realized that the picture had been copied from the contact's QRZ.com page. Google Images is another easy way to find relevant pictures to illustrate blog posts about places you have worked or are writing about, but if you copy images found in this way you almost certainly don't have permission to use them on your own site.

If you have to seek permission before using an image of someone's station, by the time you receive it the topicality of the posting will have been lost. And no ham blogger is going to pay for permission to use a copyright image from a library to illustrate a post, because no-one is making money out of ham radio blogging.

Not using pictures would make many blogs rather dull. But there isn't really any difference between copying someone's website template and copying their pictures. Just because they are fellow hobbyists doesn't mean they don't deserve the courtesy of asking permission before we use material they have created.

Saturday, January 23, 2010

Activation of Binsey

It was a bright, if chilly morning, and so Olga and I decided to go for a short walk followed by a sauna and soak in the hot tub at Armathwaite Hall, where we are members of the health club. The target for the walk was Binsey, a minor hill on the northern edge of the Lake District. It is a pleasant, easy walk, with great views on a fine day. It is also both a Wainwrights On The Air (WOTA) and a Summits On The Air (SOTA) summit.

A quick call on 145.500 before our picnic lunch raised no-one. I did hear a G7 who was raising money for the lifeboat association but he didn't hear me.

After lunch I called again and was replied to by Keith, G0EMM in Workington, who was alerted to my call by his daughter (thanks Rebecca!) After a chat with Keith I was called by Steve, M0IGG on Walney Island. He was a strong 59 signal and I thought the island must be in the Solway which I could see from my summit location, so I was amazed to be told Walney Island is in Morecambe Bay off the south coast of Cumbria. The entire Lake District was between us, but I have had good signals from the south Lakes on Binsey before and can only assume that some kind of ducting occurs.

Whilst I was there Lynn, KJ4ERJ, author of the APRSISCE software sent me an APRS message. He had spotted my movements and realized I was off for a hike. The software performed very well, but I turned the phone off on the summit to save the battery and obviously didn't wait long enough to get a fix after turning it on again so it didn't track our descent.

I forgot to turn the phone off while it was in my jacket in the locker at Armathwaite Hall and returned to find a rather hot phone displaying some odd error messages that I couldn't get rid of and a low battery, so I turned it off completely until we got home.

It turns out I wasn't the only person out on the Lakeland fells with a radio today, however I missed the activity by M3WJZ/P and M3ZOO/P that was spotted on the WOTA website as I had switched the APRS WOTA alerts to a bulletin message which APRSISCE doesn't support yet.

Sadly I have been told by Steve Dimse who runs findu.com that I shouldn't be using his CGI script to send APRS messages from the WOTA server as "use of findU by machines is not permitted" and if I want to do that I should connect to the APRS network myself and send the messages. Unfortunately I have neither the technical knowledge nor, probably, the necessary permissions on the web server to write and run my own CGI script. If anyone can help me out with that I'd appreciate it. In the meantime I'm just hoping Steve doesn't notice the very occasional WOTA bulletin message because I think it's a very useful facility that could do a lot to encourage the use of APRS in this neck of the woods.

eHam.net review updates

Yesterday on the Elecraft reflector Aptos head honcho Eric posted a request for people to submit new reviews of Elecraft products at eHam as "some of the eHam review categories are getting stale." Since he had helpfully provided a link to the K3 review category I took a look and sure enough since my updated review of November 24, 2009 there had been only three new reviews prior to Eric's call to action, and two of those had given less than a 5/5 rating.

I looked back through the reviews and was dismayed to find that my lengthy and not entirely complimentary review of September 18 in which I gave the K3 4/5 had been deleted. At first I suspected something sinister was going on. However my attention was eventually drawn to the review guidelines which state: "Multiple reviews of the same product by one person unfairly skews the product ratings. If you submit more than one review for the same product your older reviews will be removed. If you want the content of your older reviews to be in your updated review then you are responsible for cutting and pasting your old review content into your new review."

But eHam.net doesn't always do what it states. For example, two fulsome reviews of the K3 by AD4C are present, one on September 5, 2009 and one on November 26, 2008. Finding these helped restore my belief in my sanity, because I was sure that I had seen others post updates to earlier reviews that were still present on the site.

It's a pity that eHam.net doesn't make this policy clearer - for example, by warning you when you are about to post a review that it will cause the removal of an earlier one - and that it doesn't apply it consistently. Otherwise one might be forgiven for jumping to the conclusion that skewing of the results is acceptable if the direction is favourable towards an advertiser.

Friday, January 22, 2010

Ten metres is open

I decided to use WSPR to look for signs of propagation on the 10m band and found there is quite a bit of activity at the moment. From my location in northern England the propagation appears mostly to be into Germany, France and Italy but some stations in southern Europe were receiving signals from FR1GZ (RĂ©union, in the Indian Ocean).

I ventured on to PSK31 and managed to log a contact with Sylvain, F4FRQ in the eastern part of France. However no other stations were seen or heard and I went back to WSPR monitoring so I could spend my time on something more useful.

Tuesday, January 19, 2010

HT Saver

One of my ham radio pet hates are those SMA sockets used to mount the antennas on all modern VHF/UHF handheld radios. They are very fragile, and not designed for the repeated changing of antennas that most of us go in for. I don't see any justification for using them except on those very slim credit card sized handhelds which are pretty fragile devices anyway. But all the manufacturers now use them so we're stuck with them.

With the Kenwood TH-F6A / TH-F7E you really have no choice to switch antennas if you want to make use of the shortwave receive capability because the VHF/UHF antennas are useless on shortwave. Last week I made a shortwave receive antenna for it which I called the Wonder Whip. This antenna works on 2m and 70cm transmit as well, but it is a bit long to leave on the radio when carrying it so I still need to remove it quite frequently.

I made the Wonder Whip on a BNC connector so I needed to use a BNC to SMA adapter to use it on the radio. The trouble with the readily obtainable BNC to SMA adapters is that they do not have a large base that clamps down on to the body of the radio for extra support like the supplied antenna does. This means the SMA adapter takes the full force of any sideways knocks. It is very easy to snap off, as many HT owners have found to their cost. So when I saw some SMA to BNC adapters with a large base being sold very cheaply on eBay by a Hong Kong trader called PartsPipe I ordered a couple of them. The pair cost less than £5 including postage and they arrived in just over a week which is one of the quickest shipments I've had from the Far East.

To my disappointment I found that when screwed on to the TH-F7E as far as it would go there was a gap of about one millimetre between the base of the adapter and the radio. Fortunately I found a steel washer that slips over the SMA antenna connector and fills the gap. I will probably be able to get a matching brass washer at a local DIY store but the steel one will do for the moment. Now any BNC antennas will be fully supported by the body of the radio.

If I use only BNC base antennas from now on I can leave the adapter permanently in place and will not have to keep connecting and removing things from the SMA socket, which I think is rated for only something like 100 connections. I think this is a much better solution: BNC connectors are more robust and in the unlikely event you do get a problem you can just replace the inexpensive adapter - which is why I got two of them!

Now I just have to decide what to do with my arsenal of SMA-based antennas. Probably flog them on eBay!

Oops!

This morning UPS delivered an order from CPC Farnell.

You can see why they have earned the name "United Parcel Smashers." Olga was reluctant to accept the parcel as it was so obviously damaged, but the courier didn't want to take it back and said to contact CPC if there were any problems.

Fortunately the box just contained components and a couple of other rugged items, so there was no actual damage.

Britain's betrayal of St. Helena

I was deeply disappointed to learn this morning that the British government has decided not to go ahead with plans to build an airport for one of its last remaining colonies, the remote South Atlantic island of St. Helena. The decision was actually announced on 17th December but received no publicity here in the UK. I only found out after seeing a new article on the BBC website about life on St. Helena.

I have a particular attachment to the island of St. Helena as I visited there in September, 1999. For many years prior to that visit I had a fascination with the idea of life on remote islands, and even dreamed about going to live on such a place. A chance contact with someone living on the island - Julian Cairns-Wicks ex-ZD7CW, though it was not in fact by ham radio as I had given up ham radio at that point - led to the opportunity to visit the island for a holiday.

Access to St.Helena is only possible using the island's ship, the RMS St. Helena. The shortest and least expensive route involves securing a place on one of the Royal Air Force flights serving the Falkland Islands which stop at Ascension Island, then voyaging for two days on the ship. I was fortunate to be able to travel this route (which then was a lot less expensive than the prices given in the BBC article) because the other, more expensive route involves flying to Capetown, South Africa and then a five day sea voyage. The journey still took five days each way but I did also get the chance to explore Ascension Island, another British colony that has no civilian population except for employees of the military base which is leased to the Americans and used by them for communications as well as a refuelling stopover for the Falklands flights.

It is difficult to convey my impressions of the island except to say that it cured me of the idea that going to live on a remote island was the solution to the problems that troubled me at that time. The island is very beautiful, and the climate warm if a bit humid for my liking. But it is also very small - only a few miles from one end to another - and nothing happens there without everyone soon knowing about it, an atmosphere that I found claustrophobic.

It is also extremely poor. The BBC article says that the average wage on the island is just £70 a week (about $110 US) and I don't think it was much less than that ten years ago. Not only that but the cost of things like food, clothing and fuel are far higher than they are in Britain due to import costs, while phone and Internet access is limited and extremely expensive due to the monopoly on communications held by Cable and Wireless. It is one of the few places on the planet where ham radio could have an actual practical benefit. In fact I seem to recall that I could have got a ZD7 ham license just by going to the government office and paying a £15 fee. However, my host's transceiver was not in use due to TVI and another ham I'd got in touch with left for South Africa for medical treatment on the ship I arrived on so I didn't have the opportunity to use radio at all while I was there.

The air of poverty about the place made me feel a bit uncomfortable about the fact that I was wealthy enough to go there as a tourist. I spoke to a group of young Saints (as the inhabitants are called) and they opened my eyes to what life on a remote island really means for those who live there. "I expect you think it is a paradise", they said, "but to us it is like a prison." Ordinary Saints can't afford the fares to travel off the island, even to seek employment. Their only chance of leaving is to get a job serving the British military bases on the Falkland Islands or Ascension, where they are used as cheap labour on two year contracts that don't even allow for a trip home to see their families during that period. Although they are low-paid, they can still earn much more working for the British forces than they could staying in the island, so those who get the chance are happy to go. There is little employment on the island, since it produces nothing of any value and there is very little tourism due to the difficult access.

There had been talk of building an airport for many years, even at the time I went there. Successive British governments had commissioned a series of expensive reports from consultancy firms, which were all eventually shelved as the political will was not there to spend the money and actually build it. Every delay meant that projected costs escalated, but in the last few years it had looked as if the airport was actually going to be built. If you Google "St. Helena airport" you will still find sites claiming that the airport was expected to be finished in 2010, or more realistically 2011 or 2012. So it was quite a shock to me to discover that construction hadn't even started, and that it was now not going to be built at all.

The island's ship, the RMS St. Helena, is already very old and was scheduled to be retired this year. It is subject to increasingly frequent breakdowns, which can sometimes result in a shortage of food on the island. Axing the airport project will mean a decision will need to be made on how to maintain access to the island. Building a new ship will not be inexpensive. If access to the island is left to private companies it is likely to become even more difficult and expensive, leaving Saints feeling even more isolated than they already are.

Saints, despite being governed by Britain do not have full British passports and do not have an automatic right to come to Britain. This is because governments of all persuasions here pander to the endemic racism in British society that views with horror the prospect of a large number of dark-skinned people suddenly migrating here. In fact there are only about 5,500 Saints and it is likely that most of those who did come would only stay for a few years to make some money and then return home. St. Helena has retained values that Britain has long since lost and people who have been born and bred there won't feel at home here. When the island of Tristan da Cunha was evacuated after a volcanic eruption in 1961 and the 300 inhabitants brought to Britain the majority took the next ship back the following year.

I consider the British government's treatment of St. Helena and its inhabitants to be disgraceful. Centuries ago St. Helena was an important staging post for British shipping and a key base for the British navy. It played a major role in securing the economic and military might of the British Empire. But the opening of the Suez Canal meant that ships going to and from India and Australasia no longer called there, and the development of artificial fibres meant that the island's only export, flax (which was made into rope and British Post Office mailbags) was no longer needed.

St. Helena is now just a drain on the British economy. Though governed by Britain Saints don't have a vote that counts in the British parliament. The island government, which is elected, is effectively just a local council. The island governor is a civil service post and is decided by Britain. The governorship is probably the Foreign Office career equivalent of being sent to Siberia so is unlikely to attract those of the calibre to fight for the island's interests. Much the same could be said of the other British government appointees, a few of whom I met, who nevertheless were enjoying the life of Reilly on British civil service salaries plus overseas allowances.

St. Helena is treated by the UK government as a cash sink with no votes to be won or lost by decisions that are made. Nevertheless the amount St. Helena costs the UK - £20m a year according to the BBC article - is trivial: far less than Britain hands out in aid to countries that were never part of the Empire or Commonwealth and a pittance compared to what is squandered on the vast European Union bureaucracy or has been pledged to the hopeless task of preventing climate change.

With a bit of imagination and a bit of spending, including the commitment to build the airport and make easy access possible, St. Helena could surely become self supporting. Although the island is small, it has a great potential for tourism. It is home to the place where the French Emperor Napoleon was imprisoned until he died, which would ensure a steady stream of visiting Napoleon enthusiasts. And it has some unique flora and fauna including the St. Helena wirebird, which would make it of interest to nature tourists. It would probably be a popular destination for contest groups and others looking for "DX holidays." The economy could also be boosted by establishing the island as a free port or a tax haven.

The way this country has turned its back on this former colonial outpost makes me ashamed to be British and I shed a tear today for poor forgotten St. Helena.

Sunday, January 17, 2010

Out on Sale Fell

An outside temperature of 6 degrees and a sight of blue sky and the sun made us decide to go for a walk in the hills after morning coffee. I had thought of going to Whinlatter and Lord's Seat but after we set off we could see it was grey and gloomy over there so I decided to visit Sale Fell instead. As it happened, we didn't see the sun there either and an icy cold wind made it feel much colder than we expected!

This was also the first portable outing for APRSIS-CE on my HTC Touch mobile phone. Unfortunately it was not entirely successful. I found that the program does not track your position when the screen is blank or the phone is on standby, although it does remain connected to the APRS network and can receive APRS messages. Also the program kept closing while the phone was in its case. So my position was only logged sporadically as I stopped periodically to wake up the device, look at the screen and restart the program if needed. I think there are some issues with using the program on a battery-powered device that need to be looked at. On the plus side, doing it this way the battery drain was much less than leaving the GPS active all the time and the battery was still 75% full after more than 3 hours away from the charger.

Although the position tracking was a bit of a disappointment, the ability to communicate using APRS text messages was very successful. I received a message from Colin M6XSD to say "Are you on your way up Sale Fell?" I let him know when I would be on the top. Unfortunately we didn't make contact: I was only running a handheld, he was mobile in his Land Rover and a large lump of rock called Lord's Seat was between us.

I also received a message from Keith G0EMM who saw me on my way home. It was nice to have this extra way to contact friends while I was out and about. And if you were out alone on the fells it's good to know that people are tracking your position in case you should have an accident.

Due to the wind I didn't stay long on the summit. Not only was it bitterly cold but I had to press the TH-F7E to my ear to hear the radio over the noise of it. My CQs managed to raise one Scottish mobile station though, so at least I managed to log my first Wainwrights On The Air activation of 2010.

Friday, January 15, 2010

Springtime for shortwave

Spring is my favourite time of the year. The days are getting longer, the temperature is getting warmer and everywhere looks brighter as green shoots appear in the woods and gardens and the early flowering plants start to appear. Spring may be a fair way off yet but we definitely seem to be in the spring of Solar Cycle 24, with a solar flux of 90 and a SSM of 34, and it's cheering me up no end.

A post by Paul, WW2PT prompted me to try 17m for a change, and there was a fair bit of activity over the kind of distances one would only have expected on 20m a few weeks ago. I made several PSK31 contacts before lunch including a new country for me, 7Z1HL in Riyadh, Saudi Arabia.

There was quite a pile-up on Harry but he was a snappy operator sending just his name and a report and I'm glad to say that everyone I saw working him were equally brief in their replies, so he was making a contact every minute or so. I was pleased to get this one in the log using 25W to my MFJ magnetic loop in the attic.

Ham Radio Safari

I recently stumbled across a new blog that is really worth reading: Ham Radio Safari. It is written by Jack Dunegan, 5X7JD, an American ham who recently moved to Uganda to take up the post of Senior Management Leader of Aidchild, a project that provides homes for children with Aids.

Although Jack is setting up a "regular" radio station and even considering getting a linear amplifier he has a great interest in QRP, QRSS and beacons. I suggested that he might consider using WSPR and he replied that he will look into it. One problem is that the power is unreliable over there so he needs a backup power source.

It would be very interesting to have a WSPR beacon in Uganda to investigate propagation from and to there and I have told Jack to just ask if he needs any advice or assistance.

Thursday, January 14, 2010

Why SDR doesn't excite me

In his latest blog post Dave Richards, AA7EE writes: "I have an interest in SDR. At this stage in the game, I would imagine that almost anyone with an interest in radio, whether amateur radio or any other kind of serious listening, would find SDR very compelling." I'm afraid I don't. In fact I find the idea of SDR depressing, even repelling. And that isn't just because I prefer the look and feel of a real radio with buttons and knobs to a computer screen.

I say this even though I am a programmer of sorts. I have tried to learn how SDR works with the idea that if I could write my own SDR software it might become an aspect of the hobby I could get interested in. But I can't. The math is totally beyond me and I just can't understand how it works at all. The majority of radio amateurs without any knowledge of programming don't have a chance. Which makes the limit of most people's technical challenge in an SDR future that of getting somebody else's SDR software to work. And after a lifetime working with computers frankly I don't find faffing about with PCs very much fun.

A basic understanding of electronics is one of the prerequisites of getting a ham radio license. Although most of us could not design an Elecraft K3 and many of us choose never to design or even build any part of our station, most of us can understand how radio circuits work and quite a few of us can build simple circuits from a schematic. Some of us can even design circuits from scratch - a lot more of us I'd wager than could write their own SDR software.

The reason I don't like SDR is that it reduces the majority of us to the role of appliance operators. That may be fine for those who are happy being appliance operators and just want the best technical solution for working weak DX or amassing the most contest points. But for the tinkerers and builders SDR doesn't leave a lot to experiment with, because most of the interesting stuff happens in software, inside the computer, where we don't have the tools or the knowledge to tinker with it. If you are using a SoftRock or a top of the line Flex you will be looking at the same software user interface. And I don't find that a very enthralling prospect.

Fieldfare!

This morning's snow is already melting so I had to act quickly to catch a picture of our winter visitors before they depart. This was one of the results. You can see some vignetting on the left hand side (I didn't want to risk the bird flying off while I tried to eliminate it) but it is the best picture I have made yet.

This morning I had the great pleasure of meeting fellow bloggers Adam, M6RDP and Paul, PC4T for the first time on the air - also a rare excursion on to SSB for me! Conditions were very up and down, and for much of the time both stations were down in the noise and hard to copy even with the K3 DSP noise reducer, but at times Adam's signal was peaking over S9 - very good for 10W.

It will be nice to make this a more regular event under hopefully better conditions.

The cuckoo in the nest

The January 2010 issue of CQ Magazine arrived here yesterday. My attention was caught by a news item that one US state or county had received federal funding for a network of D-Star repeaters that would be available for regular amateur use when not in use for emergency communications. This will presumably be regarded by some as a win for amateur radio, getting a repeater network for nothing, but to me it looks too much like consorting with the enemy.

I know that a lot of my readers, particularly those from the USA, disagree with my views about emergency communications and amateur radio. To make it clear, I have no issue with amateurs using their skills and equipment to assist emergency services on an ad-hoc basis, just as any public-spirited person would use any skill they possessed in an emergency. But I do not believe that amateur radio and emergency communications can coexist all that comfortably - see Larry W2LJ's comments about Haiti and the foxhunt for one example - and I disagree with amateur radio being promoted as a volunteer emergency communications service as the ARRL is doing. I don't believe that getting the numbers up by encouraging people with no interest in any traditional ham radio activity to obtain licenses has any benefit to the hobby.

My American friends explain to me that the amateur bands are valuable spectrum space and being able to point to their use for emergency communications is one way to prevent their being sold off to the highest bidder. But I think this is being unduly alarmist. Real estate is also valuable but we have public parks and national parks set aside for recreational use and protected from development. Surely a good enough case can be made for reserving some small segments of spectrum space for use by private individuals for recreation, experimentation and self-training, as well as ad-hoc emergency use?

The idea that amateur bands could be sold off seems neither more nor less likely than the idea that government agencies, having paid for an amateur repeater network, then decides to keep it for emergency use exclusively. The step after that could be the sectioning off of segments of bands for emergency use only, to keep casual users from interfering with them.

I hope emcomms does not turn out to be the cuckoo in the nest for American radio amateurs. For what happens in the USA tends to have an impact on the rest of us.

More snow!

We had almost lost all the snow that fell over the previous couple of weeks. But last night there was a fresh snowfall and we awoke to a couple of inches of the white stuff.

It does make for a nice picture - the photo above is the view from our front door this morning - but I had hoped we had seen the last of it and that we might return to the mild temperatures we normally get. (I can remember winters when we hardly ever had a frost.)

The streets where we live have not been gritted and as you can see from the picture we are on a hill. Fortunately we don't have to go anywhere except for into the town now and again for supplies which we can do on foot. Otherwise I think I would be starting to regret exchanging the Suzuki 4x4 that we had for our present small lightweight two wheel drive Hyundai which is not really designed for such conditions.

Wednesday, January 13, 2010

First attempt at digiscoping

Adam, M6RDP caught my interest the other day when he wrote about a digital camera adapter that lets you take photos through the eyepiece of binoculars or a telescope. There have been many times I wished I could take a picture of what I could see through the spotting scope when watching birds. I decided to investigate and ended up at the same site where Adam bought his binoculars. The adapter pictured on his blog was on sale for under £30. That is a lot less than other similar products so I decided to get one now rather than regret not getting it later.

The gadget came this morning. First attempts to use it were a little disappointing. It wasn't really designed for my camera which has the lens very close to the bottom of the body. With the camera platform as high as it would go the camera still could not see into the eyepiece properly. In the end, I cut a strip from a cork drinks coaster (sorry, Olga) to go between the camera and the platform and raise it by an extra few millimetres which was just enough to get the image centered.

The next problem I found is that operating the shutter moved the camera / telescope giving a blurred image. Eventually I hit on the idea of using the shutter delay so that everything had stopped shaking by the time the picture was taken. This is not ideal for taking pictures of birds which are guaranteed not to stay in the same position for several seconds! Nevertheless I did manage to take one good picture of a robin on the bird feeder, which I think is not bad for a first attempt at digiscoping on a grey day, taken through a double-glazed window from inside the conservatory.

Monday, January 11, 2010

The Wonder Whip Mk1

I have just completed the first version of what I shall call the G4ILO Wonder Whip. It's a portable HF receiving antenna for the Kenwood TH-F7E and TH-F6A that can also be used for transmit on 2m and 70cm. It allows you to use the radio's wide band receive capability to listen to the HF bands 20m - 10m plus 6m.

The project was not without its complications. In fact it took three attempts to get the antenna to work to my satisfaction. The antenna is a base-loaded short whip with tapping points on the loading coil to resonate the whip on the amateur bands and a fly-lead with a small alligator clip to select the appropriate tap.

I first thought that it would be possible to identify the best tapping point by scraping away some enamel from the coil and touching the fly-lead to it using an insulated handle. The problem is that the bandwidth of such a short antenna is very narrow and the resonant point depends very much on what sort of a ground you have and whether anything - such as my hand - is in close proximity to it. So it proved very difficult to find a tapping point that gave consistent results. What might seem the right point on the antenna analyzer can be way off when using the TH-F7E or the FT-817.

I had to realize that what I was trying to make was a receiving antenna for the TH-F7E that would be used without any ground or counterpoise, and forget about trying to get a good SWR when the antenna was put on my FT-817. I was eventually able - more by luck than calculation - to find tapping points for each of the bands. On HF the antenna should be used with the 48cm telescopic whip fully extended, but it can be fine tuned by retracting sections of the whip until you hear the loudest signals or noise. Retracting the whip provides quite a range of adjustment - enough to allow 12m to be covered using the 15m tap. As this antenna is intended for receive only, getting an exact match is not essential, and you should hear stations without needing to adjust the length of the whip.

The photograph above gives the critical constructional details. The tapping points were created by making a loop of bare wire and twisting the ends together to form a tag to which the wander lead can be clipped when selecting the band in use. Because the tapping points were found by trial and error I wound one continuous coil of enamelled wire and then scraped away a bit of enamel from a turn of the coil next to each tapping point and soldered it using a fine tipped bit. This was a little tricky.

If I was making another antenna to this specification I would install the tapping points first and then wind each section with the indicated number of turns, scrape the enamel and loop the wire round the tapping point before starting the next section. You could even wind each section of coil separately, testing each section for resonance before you start the next one. This would make it easier to adjust the number of turns if the resonant point does not fall exactly in the right place.

The telescopic whip I used is 19 inches (48cm) in length, in other words a quarter wave on 145MHz. In the 2m/70cm position the loading coil is bypassed adding the length of the wander lead to the length of the whip. The top two sections of the whip should be retracted to compensate for this. I have found that when using a hand-held transceiver the best SWR on 2m is achieved with a whip length that is 5 - 7 cm longer than a true quarter wave. This antenna allows you to achieve that.

After testing the antenna, the Wonder Whip was finished off by wrapping the coil in black self-amalgamating tape. This helps protect the coil and gives the antenna an almost professional appearance.

I am quite pleased with this antenna. It is a pity that I cannot make it cover 40m and 80m as well but that would require a considerable number of extra turns on the coil and would make the antenna somewhat unwieldy.

I also fear the plastic pen body is a bit fragile and would be rather easy to break. I broke it in half once by applying too much heat while soldering to one of the tapping points which melted the plastic - fortunately it stuck back together again when the plastic cooled, but I may have weakened it. I would like to make a more robust version if I come across some suitable materials. The current version at least has the advantage of light weight, and does not put too much stress on the SMA connector of the TH-F7E.

Sunday, January 10, 2010

Winter migrants

My wife and I both enjoy watching wildlife. We always put out food for the birds, and get a surprising number of them in the garden - surprising because this is a built-up area and the size of our garden is less than the footprint of a three element tribander.

Because of the snow we are seeing a lot of winter visitors. This morning we saw six blackbirds at the same time, three fieldfares like the one above photographed from inside the conservatory by Olga, and a redwing.

Trying to photograph the birds makes you realise how hard these wildlife photographers work to earn their money. We have also enjoyed observing them through the spotting scope I bought a couple of years ago from Aldi. I have it set up on a camera tripod inside our conservatory. Being such a short distance away the birds fill the field of view so we can observe them in great detail. The fieldfares really are beautiful creatures.

First WOTA of 2010

With temperatures below zero and everywhere covered in snow even at ground level, the last thing I feel like doing is going for a walk in the mountains with or without a radio. But some people do, the first Wainwrights On The Air (WOTA) activation of 2010 has already taken place.

Yesterday John G0TDM posted a WOTA spot for Ian M3WJZ who was doing a Summits On The Air (SOTA) activation of Blencathra. The WOTA server still has a bit of code in for sending spots as APRS text messages, and a message from WOTA immediately popped up on APRSISCE running on my HTC mobile phone sitting beside me to alert me to the activity. I switched on the radio and made a contact with Ian on the cold and windy top of Blencathra.

I put the APRS notification software in to the WOTA website a few months ago to test the viability of using APRS for WOTA activity notifications. I eventually decided that it was not worth persevering with as no-one in the area other than me had an APRS-equipped radio and even if they did, APRS coverage by RF was so poor that they would never receive the notifications, but I never got around to removing the code from the website. Having now seen how well it works when using an APRS client on a mobile phone I will go ahead and make this option available to all WOTA members. I think it will be very useful for Wainwright chasers to be able to be notified of activations when they are away from their computer, and it might encourage more APRS activity in the area - whether by radio or by phone - which will be useful and fun as you will be able to track where people are as they make their way up the mountains.

Saturday, January 09, 2010

The 350mph jogger

Anyone who was watching the track of G4ILO-12 this morning may have been surprised to see me whizzing along at 350 miles per hour over south-west Scotland at 10,000 feet.

No, I hadn't taken a trip by plane. I had APRSISCE running on my phone in its desktop cradle and when I noticed my icon scooting across the Scottish landscape I saw that the GPS was losing its position.

I don't know what caused this, but after it occurred I couldn't get the GPS to lock up again, even when using another application (Google Maps) and taking the phone outside in the garden to be sure it could see the satellites. I had a sinking feeling that the GPS in my phone had failed. Fortunately, after turning the phone completely off and then on the GPS started working properly again. It was certainly a worrying few minutes!

Friday, January 08, 2010

A portable HF receiving whip

Most VHF-UHF HTs (or hand-helds, as they tend to be known over here) nowadays provide receive coverage of the HF short wave bands, though only in AM mode. The Kenwood TH-F7E (or TH-F6A in the USA) is unique in that it can receive LSB, USB and CW modes as well. It doesn't use a narrow filter in those modes, so reception is far from optimum, but it is still a nice little radio that allows me to listen to what is happening on HF when I am away from the shack. Or it would be, except for the fact that it needs a proper antenna - or at least a length of wire - to receive anything. There is an internal ferrite bar antenna but it is ineffective on the amateur bands. Consequently I have made little use of this facility, and had got to the point where I was thinking about selling the radio.

A Miracle Whip or Wonder Wand works fine with the TH-F7E, but it doesn't actually fit on the radio so you need a cumbersome collection of adapters and cables to use it. What I wanted was something like a mini ATX Walkabout - essentially a base loaded whip with tapping points on the loading coil for each of the bands. This afternoon I decided to see if I could make something like that.

I cut a crimped-on BNC connector off the end of a cable, leaving about 1cm of cable protruding from the end of the sleeve. I then cut away the jacket and exposed braid to leave just the insulated centre wire. I stripped a small piece of insulation from the end of this and soldered to it the end of a 5m length of 38SWG enamelled copper wire.

Next, I found a plastic ball-point pen whose body fitted nicely over the crimped end of the BNC connector (a bit of insulating tape helped make a good interference fit.) This ball point pen body conveniently had a small hole at the other end through which I dropped a fixing screw for a short telescopic whip antenna. A blob of super-glue held the screw in place since I didn't have a screwdriver long enough to reach the screw head inside the pen body. Once the glue had set I attached the telescopic whip with a solder tag between it and the pen body. Once tightened, the tag was bent down flush with the pen body.

I drilled a small hole in the pen body that would be the same height as the point where the 38SWG wire was soldered to the co-ax centre, then fed the end of the wire through the hole. When it was all the way through I pushed the pen body on to the BNC connector and secured it with another dap of super-glue. I then wound the wire onto the pen body to form a coil. When nearly all of the wire was wound on, I secured the last few turns with a strip of insulating tape, stripped the enamel from the end and soldered it to the solder tag. I then had an antenna that looked like the photo above.

Miraculously - since the mathematics of designing a base-loaded antenna is beyond me and this had been pure trial and error - I ended up with a whip that with a ground wire attached can be tuned to a good match on 20m just by adjusting the length of the telescopic whip. Although I intended it as a receiving antenna it will be interesting to connect it to a QRP transmitter and see if I can make a contact with it.

The next stage of the project will be to try to establish tapping points on the coil to allow coverage of 17m, 15m, 12m, 10m and 6m. I really had hoped to get coverage of 80m, 40m and 30m as well, but obviously I would need a lot more turns on the coil to achieve this. I have a reel of something like 42SWG solenoid wire so I may try to make another version using this. Alternatively perhaps the lower section could be wound on a short ferrite rod to get more inductance with fewer turns. There is a lot of experimentation to be done with this.

One aspect of this antenna that I'm not too happy about is that I have to use an SMA to BNC adapter to fit it to the TH-F7E. This adapter doesn't clamp down to the body of the radio for additional mechanical strength, so the radio's SMA connector is vulnerable to stress and even damage if you knock the antenna.

Why hasn't any manufacturer come up with a ready-made version of what I am trying to make? There are plenty of amateur HTs and hand-held scanners that cover the short wave frequencies. Surely there would be a market for it?

DX heard on 80m

The temperature fell to below -11C last night. While I was tucked up warm in bed I left my K3 with KComm monitoring the 80m PSK31 band segment using my attic end-loaded short 80m dipole. KComm decoded and logged 177 different stations, shown in the map below.

I received DX from Asiatic Russia, the Caribbean, North America and Canada. KP4ED was heard at 0213, VA3DHJ at 0336, AG4QX at 0457 and NJ1H at 0828. If I heard them, I could probably work them, though even that prospect isn't enough to lure me from a warm bed in the middle of a winter night!

Thursday, January 07, 2010

Ham radio could prevent Alzheimer's

According to a BBC news report, scientists in Florida have produced some research that suggests mobile phone use could help protect against Alzheimer's disease. The experiment was conducted on mice, which raises some interesting questions such as what were mice doing using mobile phones and how can you tell whether a mouse has Alzheimer's anyway?

Joking aside, the studies showed that exposure to certain radio frequencies protected the cognitive ability of mice that had been genetically altered to develop beta-amyloid plaques, which are not something you hang on the wall but a marker of Alzheimer's disease, apparently. The scientists are now investigating different frequencies to see if they can get better results.

This research has interesting implications for us radio amateurs. For somebody such as myself whose memory is getting so bad I had to keep switching back to the article to remind myself what I was writing about, I can't wait for the results of the research to determine what is the most effective frequency. Perhaps I should bring the magnetic loop down from the attic and sit it on the desk beside me to get more benefit from the radiation. If it is really only GHz waves that have the benefits then perhaps I should invest in an Alinco DJ-G7. Though as nobody else round here works 23cm I'd end up talking to myself, which would result in other people thinking I'd got dementia.

Perhaps this news could result in neighbours being pleased at living next door to a radio amateur and actually encouraging them to put up bigger antennas and more power. Properties sited next to a radio mast might even see a rise in value. Well, it's nice to dream!

PSK31 on your phone

I don't really think Windows Mobile is a very good operating system for mobile phones. It seems needlessly complicated, a bit like Windows for desktops. But just as I use Windows on my desktop computer in the radio shack because I'm not willing to limit myself to the rather poor choice of ham radio software available for Linux, so Windows Mobile offers the best choice of ham radio applications for a portable computer that happens also to be a mobile phone.

A good example of this is PocketDigi by Vojtech Bubnik OK1IAK. I last tried this a few years ago when I had a Dell Axim Pocket PC, though I never used it on the air. Since then, Vojtech has added support for a number of popular digital modes, so the program supports not only PSK31 but PSK63 and 125 as well, plus RTTY, MFSK and several more. It can decode CW as well.

To test it out I just put the phone near one of my speakers connected to the K3 and turned the volume up loud. This is far from ideal, but I did manage to decode a few stations on 20m this morning. One of the accessories available for my HTC Touch Pro is an adapter for a headset, with separate jacks for microphone and headphones. This would be ideal for connecting to a radio. You could make a tiny portable digimode station using this and an FT-817 or even a PSK-20? You probably think the phone is bigger than it is, but the picture above is more or less actual size.

One annoying feature of the FT-817 - and one of the reasons I never actually tried PocketDigi on the air - is that Yaesu stupidly did not allow VOX in DATA mode when the rear ACC socket is used. Someone sent me an audio VOX circuit but it required an audio transformer that I couldn't obtain. But if I can manage to make a suitable interface it would be an interesting thing to try.

If you don't have a Pocket PC or a Windows Mobile phone you can still try PocketDigi. There is an x86 version that will run on a Windows desktop. It's rather basic compared to most digimode applications, but if you are using a very old and underpowered PC with a low resolution screen it could be just what you are looking for.

Wednesday, January 06, 2010

APRS phone

I finally succumbed to the idea of using a mobile phone for APRS. It arrived today. The phone is an HTC Touch Pro Windows Mobile phone. It isn't the latest model, but it's one that I knew would run the APRS software I wanted, APRSISCE by KJ4ERJ, and I got it for a very good price from Expansys. Though not visible in the photograph, it's one that has a real (if small) QWERTY keyboard that slides out from the back. So apart from APRS it will also be useful sending and receiving email and surfing the web when I am out.

Unfortunately my phone company 3 UK's account servers were down today so I was unable to log in and add unlimited internet to my package. I had to do it over the phone. This worked out rather well, as because I have had my account for more than 18 months and have not taken advantage of a free upgrade phone they gave me the internet add-on for free. So I have all the minutes and texts I could ever use, plus "unlimited" internet, for £15 a month, which I think is quite a good deal.

Unfortunately I don't think the internet package will start until 15th January (I had a bit of difficulty understanding the Indian gentleman who took my call) so I won't be able to use the internet (and the APRS software) out and about until then. But the phone can use wi-fi so I was able to install the software and get it running from inside the shack.

I was very impressed with the performance of the phone's GPS, which picked up signals from several satellites from inside the shack. APRS text messaging works really well - faster than ordinary mobile phone text messaging in fact. It is also faster and more reliable than APRS text messaging over amateur radio, which always seemed a bit hit and miss.

I do feel a bit of a cheat doing APRS this way, but the functionality is just so much better using the phone. The map display of the APRSISCE software is far more useful than the display of the VX-8E, and the compact self contained phone is much more convenient than using a portable GPS linked to an APRS tracker and separate radio.

Since the mobile network will relay my position reports to the internet I can be tracked and receive messages anywhere, not just when in range of an APRS digipeater or gateway. I no longer need to run a (cough, unattended) Internet gateway in order to connect myself to the APRS network. And that simplifies things in the shack a good deal. I have already released the FT-817ND from 2m duty and returned to using the K3 and transverter. So it's smiles all round.

If you have APRS capability feel free to send a text message to G4ILO-12.

Monday, January 04, 2010

Dancing on ice

The longest continuous cold spell I can remember goes on, with the temperature forecast to fall to -7C tonight (it reached -8.4C last night) and it is not predicted to rise above freezing all week. Getting about is a nightmare as councils are running out of grit to treat even major roads. Minor roads and pavements of course have never been treated and are now like skating rinks.

This is what you get when you have a country run by accountants who fail to understand that when emergencies occur - whether it is the recent floods or a long spell of cold weather - you just have to find the money to deal with it. It is ridiculous expecting people to put up with chaos because there isn't money in the budget. When the banks were on the verge of collapse the government broke its own budgetary rules and spent billions of our money trying to save them. But when funds are needed for emergencies closer to home the rules can't be bent and we can't have them.

Many schools have been closed for the first day of term because health and safety rules and the litigation culture mean that councils are frightened if children slip and injure themselves on school premises they will face claims for damages. Meanwhile accident and emergency departments are overwhelmed with injuries due to people slipping over on untreated pavements. If we had a government capable of joined-up thought perhaps they would realise that giving councils the resources to treat all roads and pavements might actually save money?

We have not taken the car out since the snow fell before Christmas, as I am nervous of driving on ice after losing control of the car on ice one day a couple of years ago. But we are very glad we made the decision a couple of years ago to buy us each a pair of Yaktrak Walkers before we spent Christmas in Prague which we expected to be covered in snow (it wasn't). They are like snow chains for shoes and cost about £12 depending on shoe size. We never used them in Prague but we use them every day now and people look on with disbelief as we stride confidently past while they shuffle along carefully trying not to slip over.

Sunday, January 03, 2010

New VX-8DR

Rinse, PD2RPS, dropped me a note to alert me to the fact that Yaesu has introduced an updated version of the VX-8R (US version of the VX-8E) called the VX-8DR. The new version has several improvements in the APRS functionality, but they are pretty minor and I won't be losing any sleep over not having them.
  • Smart Beaconing Function. When using APRS for position tracking, the beacon timing is automatically adjusted to your travelling speed and location instead of using a fixed interval. This is the most useful enhancement in my opinion.
  • Heads up compass display to the GPS Screen. Your traveling direction is always toward the top of the display. This might be useful if you are using the VX-8 as a navigation device, but as it can't display maps that isn't very likely.
  • The number of DIGI-PATH route settings is increased from 1 to 7. Handy I suppose, but not too hard to work around.
  • The number of Station List memories has increased from 40 to 50. Yawn.
  • The number of APRS Message memories has increased from 20 to 30. Yawn.
  • DIGI-PATH route indication function. The APRS Packet data includes Digipeater routing info. Yawn.
  • The Message received LED flashing rate is selectable. Zzzzzz.
If you are not as underwhelmed as me by these new features then you'll be interested to know that the old model can be upgraded - but disappointed to discover that this can only be done by returning the radio to Yaesu. It is not, apparently, field upgradeable using your cloning cable. I'm guessing that this may be because Yaesu licensed the Smart Beaconing code from HamHUD Nichetronix and by making it a DIY upgrade there would be no way to ensure that everyone who applied it paid for it.

I think Yaesu missed some real opportunities here. Predictive text, as used in any mobile phone, would make APRS text messaging much less tiresome. And, even without maps, the ability to display your position graphically relative to other received APRS objects - and the ability to enter objects manually - would turn the radio into a half-useful navigation device.

This upgrade is currently only available in the USA. The European VX-8E will presumably need a different upgrade.

Best APRS client?

In a comment to yesterday's post about APRS, Chris G4HYG drew my attention to an iPhone APRS app called PocketPacket. In my quest to find out more about it I stumbled across another APRS client for mobile phones called APRSISCE. Written by Lynn, KJ4ERJ, it's for Windows Mobile based phones not the iPhone, but as I haven't yet chosen a phone that's no problem for me. What's more, Lynn is porting it to the Windows desktop platform. It looks like this could become the best APRS client for Windows - and what's more, it's free!

The screenshot was taken from the Windows desktop version, which is called APRSIS32. It doesn't look pretty, but that's because it is a direct port of the Windows CE version, and Windows CE doesn't have all the fancy user interface widgets of its big brother version. On the plus side, the program is extremely lean and mean, which appeals to me.

APRSISCE/32 has built-in support for OpenStreetMap.org mapping, so there is no messing about installing maps for your area, and certainly no need to buy maps for your area because they are free. I did have an initial difficulty getting the program centered on my location, mainly because the zoom in/out slider on the left hand side works counter-intuitively for me - clicking + zooms out to show more area instead of zooming in as I expected.

The program has integrated support for APRS messaging as well as APRS email. Information about an object can be obtained just by clicking on it, and you can send a message to that station direct from the info box. Tracking a moving object appears to happen automatically if you click on it. As I say, the interface doesn't look pretty but it is very well thought out.

Now imagine this application running on a Windows Mobile device connected to the internet. In the top right-hand boxes which show dashes on the desktop version it will display your speed and distance travelled. The map shows your position, and the position of any APRS objects around you. It's really a very useful direction-finding GPS as well (obviously you need a Windows Mobile device with GPS built into it.)

APRSISCE/32 doesn't currently support communication with a TNC, so it can't be connected to RF. But Lynn is currently working on it.

I think this is probably the best APRS client for mobile devices, and the fact that it is for the relatively open Windows Mobile platform rather than the iPhone - which you have to "jail break" to install applications from a source other than iTunes - is a definite bonus for me. Plus of course the hardware is cheaper. The only difficulty is deciding which phone to get that will run it from the dozens of possible options.

The other thing I like about this program is that Lynn is actively soliciting suggestions for improvements from users via the Yahoo group which is also the download site for the application. (Pity it has to be a Yahoo group, but you can't have everything.) So if APRSISCE / 32 doesn't do what you want today, there's a chance that it soon will do.