2 May 2010

8.97kHz noise levels

DK7FC has delayed further DX tests on 8.97kHz because of thunderstorms in Germany. Stefan comments that the noise levels appear to be rising as thunderstorm activity increases as we move towards summer. He is wondering if further VLF DX tests should be postponed until the autumn when the noise will lower again. You can check UK thunderstorm activity on the Nowcast website.

QRP AM TX for 12m or 10m (ON6MU)

Just spotted this little circuit on ON6MU's website: it's a small 100mW QRP AM transmitter for either 12m or 10m using a single stage modulated crystal oscillator. AM can be quite a lot of fun on 10m around 29-29.1MHz.

Back on the air and 10m Es

This evening I finished repainting the bedroom shack and got all the radio gear back in place. Connecting the antennas I noticed sporadic-E on 10m this evening with a CN8 audible on SSB: the Es season's started, so I'll be looking out for some QRP DX on both 10m and 6m. As mentioned before, I'll be using WSPR on 6m when not active but in the house.

30 Apr 2010

Shack repainting

Just got back from a few days in Brittany and straight into DIY! The small bedroom used as the operating shack, and a bedroom for my little grandson when he comes to stay, was in need of a repaint, so everything was removed and the whole room is being repainted. All being well, the radio gear should be operational again by Sunday.

25 Apr 2010

8.97kHz RX started

Today I made the loop antenna for the front-end of my 8.97kHz receiver. This consists of 24 turns on an 80cms square frame (the most I could wind with the 0.2mm PVC covered wire I had). Next stage is to resonate the loop and add some gain and selectivity so it can be used with a PC based SDR such as SpectrumLab or with a stand-alone direct conversion receiver.

24 Apr 2010

My 2 year old grandson's CW


My grandson trying his hand at CW - despite being only 2yrs 5 months old!

Further 8.97kHz earth-mode tests

All being well, I'll be carrying out some more earth-mode (through ground conduction current) WSPR and QRSS tests on around 1kHz and 8.97kHz in about 10 days time. My aim is to achieve a new personal DX record for the mode using about 4W. My previous best distance is 0.3kms, but I'm pretty certain that with QRSS or WSPR this can be bettered. Remembering an earlier post, 18dB more system gain is needed to double distance using this mode of propagation.  This can be achieved by raising TX power or effectively improving the RX sensitivity, in this case mostly by better filtering and signal processing.

Got my shack back

For the last 9 days my little grandson has been sleeping in the single bed in my shack, so amateur radio activity was on  hold, especially in the evenings. Today he went back to London so the shack was free again. I went on 500kHz WSPR again with 1mW ERP this evening and managed 4 unique reports so far with best DX 306kms to PA3ABK. At the end of next week I'm planning on repainting the room, so will again be unable to operate for a few days.

G3RJV QRP lecture on the BATC streaming site

A talk called "QRP Why and How" by G3RJV is available now on the BATC website. Go to http://www.batc.tv/ and click on the 'Film Archive' icon and select "G3RJV QRP Lecture" from the drop-down list on the left hand side. The BATC site has a wide choice of videos available to view on-line as well as streamed outputs of amateur TV stations and repeaters.

23 Apr 2010

Sporadic-E season

As we approach the end of April, the first signs of the summer sporadic-E season will be appearing with decent, strong openings to Europe from the UK on the higher HF bands plus 6m, 4m and occasionally 2m. Every year there are also multi-hop openings to much greater distances such as the USA, Middle East, Caribbean and South America. This year, more stations will be using WSPR beaconing on these bands, so even fleeting openings will be noticed. My plan is to WSPR beacon on 6m whenever around and not working stations using QRP on 10m or 6m. It will be good to see some remarkable 6m DX on the WSPR database.