Sunday, 21 December 2014

Another year gone...

Today I celebrated my birthday and reflecting on the past year I realised just how much I have achieved during my first year as a bona fide radio amateur.

While I gained the foundation licence back in September 2013 it was only at the start of the year that I took possession of my first proper radio and began my first real forays into the hobby. That is not to say the end of 2013 weren’t without its highlights, remember ICube-1?

While the foundation level licence gave me access to most bands, be it at only 10W, I was not content to stay as M6GTG. I passed the intermediate in May (2E0NRD) and finally got the full licence in October (M0NRD) and have slowly been honing my operating skills.

I competed for the first time in the RSGB UKAC and other VHF/UHF contests. They have proved to be an enjoyable and educational activity. The structure exchange helped me overcome my initial microphone shyness and the goal of improving my score each week to become more competitive forced me to improve my set up.

Construction of a headset interface and the addition of a foot switch were simple projects as was the building of a simple but effective Moxon antenna for 6m (blog post). This together with a permanent antenna pole, rotator system and upgraded coax all have helped me improve and learn. I even tried my hand at some portable operating with varying degrees of success. I have received some invaluable help and advice from people, especially Robert G1ZJP (M1MHZ) The results for the year have been coming in and I am very happy with my final positions in the various bands for a first timer and hope to be more competitive next year. .

HF operating proved initially off putting, plagued by QRN/QRM and my initial microphone shyness I veered toward the more noise immune data modes. I built a data mode interface and have had a fair degree of success with PSK/JT65 and RTTY as dabbling with a few other modes and over the last few weeks I have experimented with FreeDV and find it fascinating.

As I have become more confident I now operate voice more often and now regularly give points away on contest weekends because I like the short formalised exchange. Indulging in small talk in normal contacts is something I am not good or comfortable with but as I’ve got to know local operators I have started to join in the local nets and art of conversation is becoming easier.

The High Altitude Ballooning (HAB) has taken a back seat at present. I still have active plans to get a flight up with my own payload and have given a number of successful talks to local clubs over the year which I have enjoyed. Missing the UKHAS conference was a bitter disappointment but I still track flights and I hope to reinvigorate this interest in the spring as I get back up to speed with recent developments. 

Due to time constraints I have also mothballed plans for numerous construction projects based around the Arduino. Last months rearrangement of the shack should allow me to finally get around to finishing them.

Operating the JOTA station GB2FFC for a local scout group was very rewarding. The write up from this blog was included in the latest RSGB Radcom magazine and we hope to do it again next year. Being asked to contribute content to the AmateurRadio.com website came as a surprise and thanks to all those who have commented on my ramblings.

Another rite of passage was managing to repair my first rig, an elderly TR9500, yes it was only a modest achievement but a massively satisfying one and it has given me some confidence in purchasing second hand equipment in the future.

As well as building up the shack and continuing to improve my setup and operating I have some specific aims for next year...

Make a proper satellite contact
Satellite reception and tracking is something else that has been neglected recently, though I am still decoding FUNCube-1 telemetry daily.

Make a meteor scatter contact
I attended a fascinating presentation at the Spalding and District ARS by Robert G1ZJP about Meteor Scatter operating just before the Perseid meteor shower. I have made a couple of attempts since including during the recent Geminid shower and while I can receive signals no problem I have yet to make a successful contact. It is definitely on the to-do list but I may need to increase the power output, maybe even investing in some amplifiers and better antennas who knows it could lead to attempting some EME!

Make a proper SOTA/IOTA activation
Next year I will be holidaying in Scotland on the Isles of Skye and Islay so want to make a better attempt at operating in these more remote operating than I did this year. I also want to take a radio up a mountain!

Become more involved locally
I joined the South Kesteven ARS last year and regularly communicate with members of the nearby Grantham ARC. There have been suggestions of operating special event stations as well as repeating the JOTA event. I enjoy the meetings and conversations and is nice to bounce ideas off each other and hope to be more involved in organising activities.

Anyway, still a few hours of my birthday left so off to enjoy a wee dram or two and a slice of my birthday cake made by loving XYL



Sunday, 7 December 2014

Repairing a Kenwood TR9500, Part3

Back in September I attempted to repair a Kenwood/Trio TR9500 UHF All-modes transceiver for a fellow club member. It had a faulty microphone pre-amp which I replaced and all seemed well but it had further issues with the receiver. Cutting his losses and wanting shot the owner sold it to me for the princely sum of £10.

I have had her back on the bench and initially couldn't find anything wrong. However in real use it become apparent that she was in fact profoundly deaf! Picking up test transmissions from the nearby FT857D or Baofeng outputting into a dummy load was one thing but it wasn't receiving anything else!

From the service manual and schematic I deduced that it could be the initial RF receive amplifier. It is a dual-gate mosfet (3SK76) It proved tricky but I managed to source a replacement on eBay and it was a simple job to replace once I'd extricated the PCB.

I can report it is now working and the video below shows it monitoring the GB3EE repeater in Chesterfield. From the coverage map I shouldn't be able to hear it but I can and reception has been marginal at best using other receivers but it repaired TR9500 doesn't have any problems.


I wonder if the rig has been subjected to a high RF field in the past this could easily have damaged the receiver amplifier and an induced RF into the microphone lead could have damaged the microphone pre-amp. It just seemed strange it having both faults.

Tuesday night is the last 432MHz UKAC contest and hope to use her in anger.

Sunday, 30 November 2014

FreeDV

This weekend I have managed to get the FreeDV program working successfully and made a couple of QSOs on HF.

FreeDV has received a fair degree of publicity recently and is a GUI application for Windows, Linux and MacOS (other platforms are in development) that allows any single side band radio to be used for low bit rate digital voice communication.

I was primarily interested in it for possible use on VHF. It is hoped that the recently introduced 146-147MHz allocation available in the UK to full licence holders (via a Notice of Variation) will be used for digital mode experimentation. I have been constructing a data mode interface for use on the old TR9000 since it can operate on these frequencies but I decided to try the FT857D on HF to get an understanding of the program.


With FreeDV speech is compressed down to 1600 bit/s then modulated onto a 1.25 kHz wide 16QPSK signal which is sent to the mic input of a SSB radio. On receive, the signal is received by the SSB radio, then demodulated and decoded by FreeDV. The appeal being communications should be readable down to 2 dB S/N, and long-distance contacts should be possible using QRP power.

There is a lot of information. videos and guides available on the FreeDV website but the basics are straightforward. The computer requires two sound cards to handle the audio to and from the radio and the speaker/headphones and microphone. One method is to use a USB 'gamer' headset but since I already had a spare PC headset with 3.5mm plugs I opted for a cheap plug in USB soundcard (as detailed below)


Once the audio devices and PTT control are installed and configured within FreeDV it is a matter of monitoring a frequency (in USB) and hopefully you can send and receive.

So far I have only managed two QSOs with Trygve (LA6UOA) and Fabrice (F4FPG) on 14.236MHz with both the audio was clearly understandable but did suffer from the odd breakup and stutter. This was probably due to the laptop being used rather than an issue with the signal as the FreeDV needs a reasonably powerful machine with a decent amount of memory.

The software is very picky, several times the audio device settings have been forgotten or it has come up with a cryptic error message:
../src/msw/bitmap.cpp(846):assert "image.IsOk()" failed in
CreateFromImage(): invalid image
This is a known issue with the Windows version and the solution is to manually remove all of the FreeDV settings from the registry. The full details of how to edit the registry are in the GOTCHA section of the FreeDV site. Editing the registry is not recommended to the inexperienced person so is not a great solution and when starting the program backup after this fix requires reconfiguration of callsign, sound card and PTT settings again.

Despite this setback it is an excellent and exciting new mode. Both Trygve (LA6UOA) and myself were first timers when we had our QSO and we were like excited school children once we were able to converse successfully. Fabrice (F4FPG) was an old hand at it and I thank him for allowing me to briefly interrupt a QSO he was having with another UK operator who I could not hear.

I would recommend using K7VE's QSO Finder website http://qso.k7ve.org/ to see who is monitoring and on what frequency as well as passing hints in real time.

Tuesday, 25 November 2014

FTDI still bricking chips?

I doubt anyone missed the recent FTDI driver controversy.

The Scottish company Future Technology Devices International (FTDI) released an updated version of their USB-to-Serial driver for Windows on their website late September and last month the driver became available via Microsoft Windows Update. It soon became apparent that these new drivers could 'soft brick' counterfeit and software-compatible clones of their chips by re-writing the USB product ID (PID) to "0000". This action prevents the chip from being recognised by drivers of any operating system, effectively making them inoperable unless the PID is changed back. This clumsy and ill thought out measure was intended to protect its intellectual property.

The ability to reprogram the USB Vendor/Product IDs is a feature of FTDI devices offered to equipment manufacturers and so most bricked devices could be reset by using the downloadable FTDI utility.

Obviously there was much outrage from the hobbyist community and FTDI were roundly criticised and as a result the malicious driver was supposedly removed from the Windows update system.

Or so I thought...

I am currently constructing another data mode interface for some experiments with FreeDV. It requires the usual PTT control driven using the RTS line from a serial port. I purchased a couple of simple TTL level interface boards on eBay which claimed to use FTDI chips.



I built up a little scrappy veroboard circuit with an open-collector drive transistor and plugged into the shack PC and everything seemed okay as this PC already had an older FTDI driver installed.

I am using another computer for the FreeDV experiments and plugged the board into this thinking it too already had a safe FTDI driver installed but instead it brought up the installing driver dialogue and appeared to go online and download drivers and install them. I really didn't pay much notice as I wasn't too worried as any malicious drivers had supposedly been pulled and sure enough after installation everything appeared to work, the port appeared in device manager.

I unplugged the board to make a slight change and was surprised when I plugged it back in the PC the driver installation dialogue reappeared followed by an error message saying driver couldn't be installed and contact the manufacturer.

The serial port now appeared in the device manager with a yellow exclamation mark saying no driver installed error 28. Examining the device details showed that the VID was still 0403 but the PID was 0000 it had been bricked! Unfortunately not soft bricked as I have been unable to reset the chips PID using the FTDI utility.

I am not exactly sure what has happened but still a case of beware when it comes to FTDI devices and I shall be avoiding them from now on.

Saturday, 22 November 2014

Yet another shack clean up

Back in January when I took delivery of the FT857D I reorganised the shack, disposed of lots of surplus junk and the resulting layout has served me well for most of the year.

As I've acquired more equipment I have found myself struggling for space and the cluttered workbench has prevented any proper construction.

Following a rearrangement in the house I had a spare 'desk' which I wanted to make of, so the plan was to move the workbench and put the new desk next to the existing desk. I had some bookshelves which were being used inefficiently and I almost threw them out but decided to make use of them by cutting them down and modifying to make new shelves to sit on the back of the desks.


I had another clean out and the remaining junk is now in large plastic storage boxes under the desk should it prove useful one day. It is still a little cluttered but I have much more room with proper access to my books and magazines.



The workbench is at the end of the shack directly under the overhead light


 It is a work in progress, but it is a much better place to work and operate in.

Tuesday, 21 October 2014

GB2FFC - JOTA 2014

Last weekend South Kesteven Amateur Radio Society (SKARS) operated the GB2FFC special event station at the First Foston Scout Group for the 2014 Jamboree on the Air (JOTA) weekend.

JOTA is an annual event in which Scouts and Guides all over the world make contact with each other by means of amateur radio, giving them an opportunity to experience wireless communication and electronics.


This was a first for both SKARS and the Scout group and we set up a SSB voice station and a data mode station primarily running PSK. The QTH was the Scout hut in the village of Foston, between Newark-on-Trent and Grantham (IO92PX)

Nigel (M0CVO) and Sean (M6ENN) ran the SSB voice station as well as supervising the popular Morse key trainer. This allowed the children to tap out their names using a crib sheet and gave them a certificate to acknowledge their achievement. Working voice proved challenging due to the high noise level in the hut due to the other scout activities. Despite this they still managed to work stations mainly on 20 and 40m. Nigel ran a Kenwood TS-480SAT into one of his own M0CVO DBD-2040 loaded dipoles at approximately 100W



I operated the data station consisting of my FT-857D and interfaces connected to a laptop running PZTLog feeding a M0CVO Magitenna at 30W. I also had my Czech morse key connected to the TR9500 acting as a sounder and they really like the military style key.

Explaining the PSK datamode and what the program was doing to young children was quite challenging. The Scout group were also running JOTI (Jamboree on the Internet) which consisted of laptops running an IRC chat application allowing world wide groups to talk to each other so the distinction between that and the slower PSK station was a bit difficult for some of them to grasp. Thankfully there were two very intelligent and enthusiastic Scouts who got the idea and understood the QSO process and were soon explaining it to the other Scouts leaving me free to type and push the macro buttons. One of them described it as 'awesome!'



GB2FFC ran from 09:00-15:00 UTC on the Saturday and 12:00-15:00 UTC on the Sunday and made 88 QSOs in total, mostly other amateurs but we did manage a number of other JOTA stations in both modes. The whole event was great fun and we were made very welcome by the Scout group. The enthusiasm was infectious so hopefully it will be the start of a regular annual club event helping out the Scouts for JOTA - plans were already being sketched out for next year, maybe involving camping!

Here are the PSK QSO maps for the weekend. Saturday was on 20m and 15m and were just European, Sunday I was operating mostly on 10m hoping for some transatlantic contacts, and did make a couple in the short time we had - didn't quite manage to connect with some South American and Asian stations but they could be seen and decoded to the delight of the children.

 

Monday, 20 October 2014

Over The Moon - M0NRD


I now have a full licence and a new call sign M0NRD.

I sat the advanced level examination held during the RSGB Convention on the 12th October. The results were due at least six working days later so wasn't expecting to know how I had done till this week so I surprised when the certificate arrived on Saturday morning and was over the moon to discover I'd passed with a distinction.

I only decided to apply to sit the exam last month. Regular readers may have missed the announcement as it was an after thought at the end of another post.

I became a licensed ‘foundation level’ radio amateur last September (M6GTG) and an ‘intermediate’ (2E0NRD) in May this year. It was a bit of a bold decision to attempt the final stage as I hadn't been actively studying for it. There have been many people who have progressed in a shorter time but going through the levels in just thirteen months is a big undertaking especially when time and concentration is taken up with work, career and domestic commitments.

After a cursory glance at the syllabus and a quick leafing through the RSGB Advance! book I had decided while there were quite a few areas that I didn't know in depth the electronics theory and mathematics were okay due to my higher education background (though it has been 26 years since I left University) so I just needed to fill in the blanks.

After posting off the application the plan had been to spend the month going through the book, learning, refreshing and revising the subjects as necessary. Of course I got sidetracked and distracted so it got left it to the last minute, well in fact to the week before the exam.

As soon as I started studying properly I soon realised I'd seriously underestimated the amount of details and facts that I need to understand and recall. I knuckled down and despite doing full days at work I studied in the evenings, making notes, working the questions on the Hamtests website and in the QADV program and gained confidence of getting at least the 60% pass rate. I tested myself on the QADV practice papers and mock papers on the RSGB website and seemed ready.  

I had intended to be at the RSGB Convention proper however I agreed instead to spend that weekend at the Mother-in-laws in Cambridge and drove over to Milton Keynes in thick fog on the Sunday morning.

The actual exam seemed reasonable there were a few head scratchers and several questions on topics I suddenly found myself unsure of. I took my time deliberating and checked every single 'licence condition' question against the supplied licence document even if I thought I knew the answer. Double and triple checking questions, values, calculations and answers and with 10 minutes of the alloted time remaining I had filled in the marking sheet and made a quick exit in time to get my Sunday roast dinner.

I had left confident and reasonably happy but over the next few days doubt inevitably started setting in. I kept remembering questions.. had I got that one wrong? I resisted the temptation to check the text book and keep thinking well it is only 60% I need...

To achieve a distinction was very satisfying, a lot of people have said they expected me to walk it but self doubt and a lack of self confidence is something I have suffered from for many years. When I was a spotty student I would probably have agreed but now an overweight, slightly befuddled middle aged man with greying hair you do have your doubts.

I would like to thank all those people who have congratulated me and those who have encouraged me along the way and wish everyone studying and taking the exam in the future the best of luck.