Month: December 2019

RSGB Intruder Watch

The radio amateur community have always been vocal, that’s not a bad thing and has been very successful in allowing us to have very privileged access to the radio spectrum from DC to daylight.

On some bands, we enjoy primary access and should be free from other users sometimes called intruders. Other parts of the bands are shared and used on a secondary non-interference basis, we amateurs must not interfere with the primary users.

The RSGB provides a number of services, one is called Intruder Watch. Volunteers take reports and will complete some initial investigation and correlation of the data. The data is then red into OFCOM the national regulator, and the will take steps to report the problem to the national regulator in the country of origin.

The issues are often international problems, and so require evidence and sometimes weeks or months of data collection.

The RSGB intruder watch team can be contacted on they ask you to provide the following information. Date, Time, Frequency, Modulation type.

If you wanted to check the latest news from the IARU, you can read their newsletter online look for the latest news.

I often report a military station on 7 MHz, today I noticed an FSK station centred on 7.193 it was 200 Hz wide and using encryption.

The Kiwi SDR network can be very helpful in providing a TDoA service

Most likely Russian Naval FSK

I think it is very important to report these issues to the IW team, in the past, OFCOM have asked for evidence they intruder is causing an issue and that can be hard to demonstrate if 1 report has been received from 50,000 amateur radio operators.

The IW team ask you to report every occasion direct to their email address, even if its the same station on successive days. This helps to build a body of evidence and hopefully results in the station being encouraged to move away from our primary allocations.

12 into 5 doesn’t go

A couple of months ago I demonstrated to myself just how 12 into 5 doesn’t go, yes I know maths (or math if you speak American).

Unfortunately for me, this was more of an electrical disaster, putting 12v into my 5v QRP Labs Ultimate 3s transmitter. The display glowed unsurprisingly bright, and then blank.

At the time I wasn’t sure why, so in true fault finding tradition I turned it off and on again, several times in fact. It then clicked, or probably more precisely popped and the damage was done.

Looking on the QRP labs help file, I found a section that dealt with “Ive put 12v on my …” I guess I’am not alone, and to be honest I really cant see why this devices wasn’t designed as a 12v native power supply and then regulated to 5v.

Part 1 involved buying a new processor, these can be purchased for a few pounds online or by speaking with Hans and buying one at one of the rallies he attends.

Here is my rather sad v3.09c with burn mark!

Part 2 in my case indicated that there was an issue with the clock. I had to re-build the Si5351A Synthesizer, again available for a few pounds. The FAQ indicates this is probably OK, but in my case it wasnt and needed replacing.

Here is the new one ready to be fitted. It just needed the header pins, but I found this really difficult as my eyes dont seem to focus on anything close these days.

Once this was installed it sprang back into life, and is currently purring away at 200 mW on 7 MHz. I have been told on occasions the display can be damaged, but despite my best efforts this survived.