Friday, 25 April 2014

Summits on the Air (SOTA), Firle Beacon


I have been off the air for a while. Building works at home meant I had to dismantle my station and it has taken me a while to get it back together again. I have also not done much portable operation for while so I decided last weekend that I would activate a Summits On the Air (SOTA http://www.sota.org.uk/) summit, Firle Beacon, SOTA reference G/SE-010 (WAB TQ40, JO00BU) on the South Downs Way south of London.

When doing portable operations, I do not believe in driving to a car park, walking 50m or worse still operating out of the back of a car. For me portable is  public transport and boots. So, first thing on Saturday morning saw me at my local station en route to Firle. Unfortunate it was a week of ‘Engineering Works’ so the journey took longer than usual. My train pulled into Southease station at 10:30am. After a quick trip to the near-by YHA cafĂ© (http://www.yha.org.uk/hostel/south-downs) to top up food stocks it was time to hit the trail. The walk to Firle is about 8km. The first part is quite steep with a 200m climb up onto the downs. 90 minutes later I arrived at Firle. On the way, I put out occasional CQs on 2m and 4m, but no one responded.

For this expedition I took a Yaesu FT-817, two hand-helds (Yaesu VX-5R for 2m and a Wouxun KG-699E for 4m, which I review elsewhere in this blog). The antenna was a Super Stick and the power was provided by a 7Ah SL AB. That, plus a small tool kit, First-aid pouch, food ‘n’ drink took my pack up to my self-imposed limit of 10kg.

Set up took about 40 minutes and I started with CQ on 40m. This did not produce any response, but I heard M0SIY/P, Simon, so I called him and got a 3-3 report from him. The Super Stick does not produce great results on 40m, but considering its overall length, this is not surprising.  I switched to 20m SSB and rapidly logged another five QSOs – enough to ‘qualify’ the activation for SOTA. I tried 17m and 15m with little success.

M0BGR/P at Firle Beacon, Easter Weekend
The early part of the day was bitterly cold and dull, with a northerly wind, and I considered moving on to another summit, or even retiring to a local pub especially when rain threatened, but I decided to stay put and do some more operating. By mid-afternoon the sun came out and the wind veered little which made everything more pleasant (except for a radio-controlled glider pilot who lost his lift!).  Later in the afternoon, 17m became a lot more active and I was able to work a few stations on CW and by 5pm, when I needed to pack up, I had 17 QSOs in the log. Best DX was UT7IA on 12m SSB at 2255km – not bad for 5W and a small vertical. You have good ears Uri!

A real disappointment was VHF/FM. I took along a couple of hand-helds to cover 2m and 4m. I broke off operating HF about every half hour to call CQ and did the same while hiking to and from the railway station. From the top of the South Downs I should have been easy to hear up to 100km away, which means most of SE England and parts of France, but I got only one response for my troubles, G3VPS on 4m – thanks Peter. VHF FM is the entry level for many newly qualified hams, but they will soon be put off if no one comes back to their early calls. Can I ask that you monitor FM whenever you can and reply to any calls you hear?

My equipment worked well during this expedition. I had a minor fault with the FT-817, the narrow CW filter stopped working, but as I could live with this I decided not to dismantle the radio on top of the hill. I was very impressed with the Super Stick antenna on 20m and above. A nice thing about operating on top of a hill is how quiet the HF bands sound, compared with my usual urban location.  It was also nice to take some time to chat to other walkers who were on the South Downs Way and explain why I was doing amateur radio on such a cold windy day.

Monday, 18 March 2013

5 MHz NoV

I decided to apply for my 5 MHz (60m) Notice of Variation so I can operate on that band. The process for Full licence holders here in UK was very easy and all I had to do was to fill out an on-line form on the RSGB (www.rsgb.org) web site and the NoV was emailed straight back to me.

I have not been on the air yet but spent some time listening This is a complicated band so I thought I had better get to know it before transmitting.

Sked anyone?

73 Dave

Friday, 7 December 2012

Software Defined Radio (SDR) - First Steps

I have often seen adverts in the amateur radio press for Software Defined Radios (SDR) and wondered why they are so expensive. During a discussion at my radio club (Cray Valley - www.cvrs.org), I learned that a TV/Radio Dongle receiver can provide the hardware for SDR. I found a suitable dongle (RTL2832 plus either R820 or E4000 chip set) on Ebay; ten UK Pounds from Hong Kong so, being the last of the big spenders, I went ahead and ordered. While I was waiting for it to arrive, I downloaded a copy of SDR Sharp  (SDR#) and the installation instructions (http://www.sdrsharp.com ).
 
There are some hardware things that I needed to do while waiting for the dongle. The dongle has a tiny MCX antenna plug. Fortunately Maplin sells an adaptor cable to standard TV socket (part N59LN) and I had already made a TV-BNC cable for another project, so this was not a problem. These dongles are very vulnerable to high levels of RF, so if you transmit while receiving on the dongle it will fry. The solution is to solder a couple of reversed diodes into the adaptor cable to limit the maximum input voltage.




The dongle arrived. The package also contained a remote control (only useful if you want to use the dongle for its intended purpose, but being radio amateurs we don’t do that do we?), a whip antenna (which works surprisingly well) and a software disk. Do not install this software as this will conflict with SDR#. The only tricky bit was changing the dongle driver from the Windows default to RTL 2832. To do this, you need a piece of software called Zadig (link on the SDR# site) and I also had to temporarily disable Heuristic protection in Norton which took violent exception to what I was trying to do.

All set, and Norton back to full protection, I plugged in the dongle and fired up the software. Operation was quite intuitive, but I started with the FM broadcast band – all was well and all the expected stations showed up on the display any gave me some strong, predictable signals to set up and learn how to use the software.
 
 

The dongle, with the E4000 tuner, covers from about 24MHz up to 1.7GHz, so it is a broadband device covering all the amateur bands from 12m up to 23cm. That’s the good news; the bad news is that there is no front-end filtering. Also these dongles mix the RF signal down to a few tens of kilohertz, to input to computer sound cards, so spurious signals are a real problem, particularly on the lower bands. For example I get a strong ‘Classic FM’ signal in the middle of the 10m band. It is possible to manage these phantom signals by carefully choosing the ‘Centre’ frequency and adjusting the RF gain, which can be accessed through the ‘Configuration’ menu, but my next move will be to build some filters to clean up the input signals.

I have also experimented with receiving  some digital modes using this SDR receiver. It is possible to patch the microphone socket to the speaker socket on most PCs so the digital modes can be decoded with standard software. There are a couple of drawbacks: you can’t hear the audio signal and the signal gets converted from digital to audio then back to digital again. There is a better solution – a piece of software called Virtual Audio Cable (  http://software.muzychenko.net/eng/vac.htm ), which does what the name suggests, but without the Digital/Audio conversions. With VAC, it is possible to ‘split’ the system so the audio output can be heard, recorded or shared with other programmes. I have successfully decoded RTTY, PSK-31 etc.

My Dongle SDR has several advantages: it is very small and everything is controlled from the keyboard so easy to configure. For example, filter bandwidth can be adjusted very precisely and easily.  The waterfall display, which can be adjusted, allows large segments of a band to be viewed at once and you can see when stations come and go then click on the ones you want to listen to. Combining the SDR with the VAC software provides a very flexible setup. For example, I can operate digi-modes while listening to my favourite music on the same computer. 

This SDR radio will never be as good as a full communications receiver, but it was definitely worth a tenner and I hope its performance will be even better with some front-end filtering. It has opened lots of opportunities for experimentation that were not available to me before and after this initial experiment, I may be tempted to invest in an SDR transceiver, but that is for another day.


Monday, 29 October 2012

10m (28 MHz) Activity

At long last the solar cycle has improved and the 10m (28 MHz) band has been 'open' during daylight hours recently.

Last weekend was the CQ World Wide (www.cqww.com) international amateur radio contest. This is a major event and as the weather was so bad over the weekend I was able to spend a bit of time operating. I decided to run just low power (5 Watts QRP, this is about the same power as a Christmas tree light!) and just one band - 10m. I was using my Yaesu FT-817 with a home-made vertical dipole in my loft. Conditons were quite good and I managed to work 116 other stations from the Middle East to USA East Coast.

Also on the 10m band, today I was able to pick up an amateur radio repeater, N2ACF/R, ( http://www.rra.net/ ) which is located in Rockland County north of New York City. This was carrying traffic for the amateur radio emergency net in preparation for the arrival of Tropical Storm Sandy, that is widely predicted to cause major damage in the New York area. I wish everyone in the path of the storm well and, while I hope the amateur radio support is not needed, I am pleased to see that the capability is available if needed.

Dave

Friday, 26 October 2012

6 Metre SMIRK Contest WInner


I am not a major amateur radio contester, but if I hear a contest in progress I will sometimes join in to give away a few points and to keep up my skill level. Occasionally, I will even submit a log.

So it was last June that I heard stations calling CQ Contest on 6m. A quick check of the contest database, which I have on my iPhone, gave me the rules for this SMIRK contest (http://www.smirk.org.) Conditions were good so I worked a few stations, sent my log off to the organisers and thought no more about it.

To my surprise, this week I received an envelope postmarked Pennsylvania and inside was a certificate confirming I had won first place in England! I checked the web site and sure enough, there I was. Unfortunately, I was the only station from England to submit a log which rather took the gloss off my achievement, but this is the only time I have ever come anywhere near the top of any contest so I don’t feel too bad about the lack of competition.

My 6m station is very modest – FT-817 running just 5 Watts and a home-made non-rotatable dipole, fabricated from some old  22mm copper pipe in the loft. But even with this, I can work all over Europe and occasionally beyond when there is a good E-opening.

So, it is worth entering contests even with a very modest score, and thanks to the SMIRK 6m club for running this event.

Dave M0BGR

Friday, 3 August 2012

Operating 2o12L and Mo0BGR

I got up early this morning to operate 2o12L (http://www.2o12L.com. Good session on 20m CW (Morse). Band condiitons were not great but lots of European stations and a few Asiatic Russians worked. I had hoped for some Far East stations, but conditions were not up to this. Unfortunately there were still lots calling when I had to close down to go to work (http://www.howardcommunications.ltd.uk) :-(


2o12L Antennas
2o12L Antennas (some of them!).


Last night, I worked CW (Morse) on 30m from my own station Mo0BGR. Someone kindly 'spotted' me on the DX cluster so I got a nice run of stations. Nothing like a 2o12L pile up, as my station is slightly more modest, but it still kept me busy for a while.

Friday, 27 July 2012

Olympic Special Event Stations

I activated my own special event call, Mo0BGR with a short session on CW (Morse) last night. Conditions were not great, but the first station I worked was UX5MZ - thanks Igor.

Meanwhile over in Eltham, SE London not far from the Olympic venues, the Cray Valley special event 2o12L is going great guns, having worked over 5,000 contacts and 100 countries since Wednesday. For more details go to www.2o12l.com where you can find a list their working frequencies. 

If you are in London, before 9th September, then try to go along and visit 2o12L, how to get there is also on the web site and it is a really impressive station.