Welcome new readers

Firstly welcome to all my new readers via AmateurRadio.com

I was very surprised, shocked even, to be asked to syndicate my postings to the site. Hopefully my posts will be of interest to a wider audience.

I have been a licensed amateur operator for six months currently on the bottom of the UK licence structure, the so called Foundation licence, but am hoping to take the Intermediate licence soon.

The main driving force for wanting to progress is I want to build things, to experiment and learn.

In a natural extension/diversion from my day job I have already been experimenting with the Arduino platform, initially with the intention of developing a High Altitude Balloon tracker but more recently with other radio related projects including a satellite tracker and using it in conjunction with DDS modules for WSPR/QRSS purposes. I have just built a dedicated Ultimate 3 QRSS kit from Hans Summers (G0UPL)

The DDS module are particularly interesting and I have some tentative plans for an Antenna Analyser and a Power/SWR meter capable of working down in the mW range which I stumbled across on the website of Loftur E. Jónasson – TF3LJ / VE2LJX. This is of particular interested to low power QRP operating. Did I mention that I have joined the GQRP Club?

Progressing from a couple of Baofeng VHF/UHF handhelds (which I hardly use) to a proper rig last month with the purchase of a Yaesu FT-857D I have been dipping my toe into the frightening world of operating!

It is common for new amateurs to be “Mike Shy” and I admit to suffering terribly. Not being the most outgoing or confident person being confronted by a barrage of rapid fire abbreviations, codes and etiquette it took a while before I had the courage to key up.

I plucked up the courage to have an attempt at some of the RSGB UKAC VHF evening contests and after gaining a bit of confidence I ventured properly onto the HF bands this weekend making a few simple signal report QSOs.

I should like to thank all those who have been patient with me as I fumble along.

Because of the shyness the use of data ‘digital’ modes is a strong draw since it uses computers and you don’t have to talk! I am salvaged some suitable connectors to build a new computer data interface for the FT-857D, I built one several years ago but it got slightly cannibalised when experimenting with an ARPS gateway.

I can afford a commercial interface but why should I pay over the odds for something I can easily build myself? The desire to homebrew isn’t just driven by cost, but lets be frank this can be an expensive hobby! Nothing gives more satisfaction when something you built works.. and yes they may be famous last words.

Ultimate3 QRSS Beacon kit built!

At the start of the year I did some experimentation with cheap DDS modules based on the Analog Devices AD9850 connected to the Arduino board, making a rudimentary WSPR transmitter prototype.

My current licence restrictions prevent me using anything home-brew for transmitting except for commercial kits. So I ordered an Ultimate3 QRSS beacon kit from Hans Summers (G0UPL) thinking that it would be okay. I subsequently learned that any commercially available kit must satisfy IR 2028 which is all a bit vague and unclear but sadly I don’t believe this particular kit does.

All was not lost, building this kit should more than satisfy one of the practical assessments of the intermediate examination, which will get me around this problem.

The Ultimate3 kit is extremely popular and so I had to wait a little for delivery and it arrived on Friday. After the last few weekends of non-radio activities I had planned to get my antennas backup and do some proper operating. Like many people I had been forced to take everything down due to the barrage of storms and high winds the UK has been experiencing recently.

A tidy workbench

Saturday saw no let up in the wind, so I decided to spend a few hours building the kit instead.

The instructions were extremely clear and straight forward and soon had it built up, though it is high time I invested in new soldering station. I have a basic Antex 25W iron. I cannot remember exactly when I brought it but it is well over 10 years ago.  It was more than adequate to build this kit and for soldering connectors but I could do with something adjustable and more comfortable.

Taking shape

The only issue I had was winding the first toroid, 25 turns later I realised I had wound it the wrong way round so the leads didn’t line up with the holes in the PCB. I could have made it fit but nope I will do it properly so I unwound it and did it again.

I also made the mistake of not scraping the enamel off the toroid wire and tried the heat it and bubble it off method, except I think my iron just isn’t hot enough so ended up using a piece of wire wool to remove the enamel.

Lessons learned I soon had the other three toroids correctly wound and wire prepared for the low-pass filter board.

Close up of the LPF

   A final visual check and powered it up and it worked first time!

All built
It works!

Setting it up

Full of confidence I grabbed my trusty GPS module which has been pressed into service on a few Arduino projects including the HAB project. Quickly soldered some connecting wires and powered everything up.. all was well or so it seemed when the display suddenly went blank, backlight was on, just no characters.

Pressing the button I occasionally got some random characters and a flashing cursor! I de-soldered the GPS and still nothing. I suspected the display was faulty but trying it on the HAB prototype board confirmed it was okay. I checked the display connector continuity and everything appeared okay.

Out with the oscilloscope I started probing, everything checked out. Crystal was oscillating and data pulses on the display control lines. Then I checked the supply pin on the display and it was only reading 4.1V, this under-voltage would explain the odd display behaviour.

PSU output was 5V, micro-controller was 5V, DDS module had 5V. All very puzzling till I removed the DDS module and spotted a discoloured track on the PCB, touching it with a screwdriver and the lacquer fell away revealing a tell tale scorch mark, somehow I had made a nice resistor!

Burnt track to right of micro-controller

A quick wire link soldered in place and everything was back to normal.

What caused it? Checking the de-soldered GPS connecting wire I spotted a stray single strand of wire on the ground wire. I suspect this must have shorted to the adjacent 5V line and since I was using a nice beefy ex-PC PSU as a bench supply it had popped the track without the hint of a flicker. The GPS has been rewired properly and is working nicely, now to connect a dummy load and experiment some more.

Sunday was a lovely day, wind dropped so antennas have been put back up and I took the opportunity to tidy up the installation a bit. I also dug out an old fibreglass pole to put the M0CVO HW-20HP back up. I didn’t get to do any operating in the end as by the time I had done this and made up a couple of decent patch leads it was time for roast beef and all the trimmings and an evening in front of the TV.

The HW-20HP back up

Putting PL259 and N-Type connectors on coax is also part of the intermediate assessment, so perhaps I should have videoed making up the patch-leads as proof 😉

432MHz UKAC – 11 February 2014

Another enjoyable evening getting familiar with my radio and competing in the RSGB 432MHz UKAC.

I rewired the 7-element ZL-Special on Monday night, and adjusted it to get an excellent VSWR of nearly 1:1 and mounted to the pole.

Setting up last night I raised up the pole around 19:30 and a quick check showed the VSWR was over 1:2!

Yesterday it rained and sleeted very heavily, as suspected the culprit was where I joined two pieces of coax. I had used plugs and a coupler but had run out of self-amalgamating tape to waterproof it, so had resorted to wrapping it in insulating tape… bad idea! Removing the tape it soon became evident that everything was very damp, I quickly dried all the connectors down and gave it a quick blast with a hot air gun. All sorted, the VSWR was back to just over 1:1 (must visit Screwfix for some more tape)

I was much more relaxed for this contest, it was an enjoyable but difficult evening and made just 8 contacts, claiming 762 points. I heard quite a few calls but just couldn’t make myself heard. I kept popping out the shack to turn the antenna, listening to other QSOs I was able to use the locator to determine the optimum bearing.

One observation I made was the apparent poor front to back ratio, some calls coming in loudly despite the antenna being in the opposite direction which suggests the phasing isn’t quite right.

The map below shows my results.

A night off next Tuesday as it’s the 23cm contest, but hoping to be better set up for the following weeks 50MHz contest, hopefully getting better results than I did last time.


View UKAC 432MHz 11-Feb-2014 in a larger map

A Radio Free Weekend!

No chance to do any radio this weekend as was away with the XYL in North Yorkshire. Packed the Baofeng but never got chance to turn it on..

I did manage to get along to Maplins at the end of last week and grabbed some expensive N-Type connectors (as well as some other connectors, a cheap dummy load and an antenna switch!) So this evening I am hoping to sort out my Moonraker 7-element 70cm ZL-Special for the 432MHz UKAC contest tomorrow night.

I have been reading up on the ZL since I have always been a bit confused by the antenna.

The assembly instructions for the Moonraker one were very poor and the joining of the two phased elements was achieved using simple straight wire, rather than the twisted transmission line I was expecting. It has worked reasonably well as a RX antenna but I haven’t used it for TX yet.

I have found a small section of ladder line from an old FM radio antenna, so will be using that now that I have more of an understanding of how it works, the front element and the larger rear element are supposed to be approx 1/8 wavelength apart (I haven’t measured it yet) the two are joined using a twisted section of transmission line 1/8 wavelength in length.

There is also a trimming capacitor to help with the matching, so with this information I hope to get things tuned up nicely, the only draw back is only have RG-58 coax at the moment which isn’t ideal for UHF, but it is only a 10m length and will be using proper N-Type connectors.

Second contest, getting the hang of it.

Spent a fun evening in the shack taking part in the UKAC 144MHz contest. It was nice and warm with the heating on and I a few bottles of beers on standby!

I was a bit more organised than the 50MHz contest last week. I got the computer running the Minos logging program. Just before 8pm I raised the antenna and double checked the VSWR and had a quick listen around on the band before the start and heard a few operators setting up. All looked good and then before I knew it we were off!

Due to my inexperience I operated in ‘search and pounce’ mode rather than calling CQ. I kept going outside and turning the antenna in a new direction and then spent several minutes searching up and down listening out for CQ calls.

I soon made a few contacts and fumbled along but my confidence increased as I got the hang of the exchange required.

I was jotting down the information and almost made the mistake of relying on the computer logging till I made an error and when attempting to correct it end up in a total mess due to my unfamilarity with the software. Thankfully I was able to sort out the log and carried on, but lost some time doing so. 

Thankfully the rain held off but the wind was blowing quite strongly and the antenna was waving about a little so didn’t have it at full height, not that full height was particularly high anyway and more often than not I suspect my antenna was pointing in the wrong direction!
  
At the end of the night I only managed 10 contacts, but was pleased none the less, scoring 930 points.

 I have made a map of my QSOs and as expected they are limited by my surroundings 


View UKAC 144MHz – 4 Feb 2014 in a larger map

Many years ago I experimented with a PMR eQSO gateway (detailed here) and when doing that I created a couple of terrain maps were created using GEOG. Geog is a suite of programs written by Andy Talbot (G4JNT), some of which make reference to a database of UK terrain heights, to provide useful information for radio amateurs (and others interested in point-point working) The software is still available on Andy’s new site

Interestingly the contacts appear to follow the direction of the Trent valley, while the surrounding hills have a masking effect. The contacts to the west in the Peak District are probably due to their height!

Roll on next week for the 432Mhz contest.. another antenna I have to sort out properly.

Antenna up ready for UKAC 144MHz

The antenna this morning

Back in 2011 my brother won a Innovantennas 4-element LFA at the National Hamfest, he couldn’t make us of it back then so I adopted it. I have used it for reception but until now not for transmission.

I should say my brother has took his foundation exam and has the callsign M6GTD, so am expecting him to ask for his antenna back at some stage! 😉

This evening is this months 144MHz UKAC contest and I spent yesterday evening getting the antenna set up properly so I could take part. Unfortunately the antenna was damaged just before Christmas and I have now replaced the boom insulators and straightened the bent director element.

It took a while to get the antenna VSWR down to a satisfactory level, not due to any fault but simply I had the adjustable sections of the active element loop too far out. They are now almost fully in, but at 144MHz the VSWR is a little over 1:1 and across the entire 144-146MHz the maximum is around 1.3:1 so I am hoping it preforms reasonably well, even with 10m of RG-58.

As suggested I have a ‘ugly’ rf-choke inline, which you can see on the photo. The antenna is clamped just under the vertical collinear, and hopefully this won’t affect its performance.

I can put the pole up to around 5m, but the top section isn’t that substantial and has a reasonable loading with the yagi and the collinear on it, but the pole it is securely guyed so for temporary use should be okay. Well that is what I thought till I saw the weather forecast

The wind speed and gusts look a little worrying, peaking at around 40mph between 21:00 – 00:00!

The only saving grace is that I will be manually rotating the antenna I will be out checking on it regularly during the contest!

Best of luck everyone taking part…

FUNCube-1 a thank you received from space!

I posted a few weeks ago about issues I and others were having decoding the telemetry from FUNCube-1. Initially this seemed to be related to a dashboard software update, but even downgrading to an earlier version has been giving variable results.

What seems to have been the issue is a reduced quality of received signal. Operators with higher gain, optimised antennas appear not to have seen problems. Why there has been such a fall off isn’t clear, the power output of FUNCube-1 hasn’t altered and appears not to be tumbling.

The FUNCube team have now released a new version of the Dashboard Software. Version 820 can be downloaded from http://funcube.org.uk/working-documents/funcube-telemetry-dashboard/ The major change in Version v820 centres on improved decoding routines which give better results, especially with weak signals at low elevations and simpler antennas.

I have been running this now for several days and can confirm it is much better, as promised low elevation passes now get successful decodes and night time passes when the telemetry is on low power get successful decodes something I wasn’t getting before.

Now I have the shack sorted I have set up a dedicated receiver using the original FUNCube Dongle using the X-30 white stick collinear and this has been pulling in decodes nicely.

This morning I had surpassed the 2000 telemetry decodes milestone, as can be seen on the rankings page.

Another nice result over the weekend was seeing my callsign in one of the FITTER messages

Rx’d my callsign in the ‘Thank You’ Fitter messages from FUNCube-1 over the weekend, nice touch! pic.twitter.com/MvJt8p6tVU
— Andrew Garratt M6GTG (@nerdsville) February 3, 2014

It is a nice touch that the FUNCube-1 have started acknowledging the receivers, hopefully with the improved software there will be more participants.

The next stage for me? Well must sort out trying to have a QSO via FUNCube-1 and the other satellites..