M1KTA's version of the 40m Flea Transceiver

Dom Baines M1KTA has just completed his version of the Flea transceiver for 40m and it looks a very neat job. Dom describes this on his blog and it is well worth a look. He gets 1.3W out from a 2N3866 PA. I look forward to working him very soon.

Gnat-1: 1 transistor transceiver from SPRAT 138

Am I alone in struggling with this design from SPRAT 138?

Today I did a breadboard version for 80m on the bench. On TX I had no problems (as long as I grounded the transistor's emitter directly on TX), but on RX the performance was diabolical and no better than a crystal set with injected carrier. I cannot quite fathom out the function of the transformer T2 or why the key is grounding the secondary of T2. As described in the article I would have thought T2 could be removed and simply key the emitter to ground on TX and decouple a larger (variable) emitter resistor on RX.

Has anyone had success with this design on RX? It may well be me!

500kHz new reporters: DL-SWL and G3JKV

No further DX records broken in the last 24 hours but a couple of new stations reporting me: DL-SWL who is in JO52 some 701kms away and G3JKV who is in IO91. Thank you for your WSPR reports.

Did my 1mW ERP reach Moscow on 500kHz last night??

This evening, Andrey RN3AGC sent me an intriguing screenshot taken from his PC in Moscow 2433kms away from here. It shows a very weak trace on the screen at the frequency which only G3XBM was operating last night. It is just possible this was my 1mW ERP signal. If so, it was too weak for the WSPR software to decode. You have to look very hard to discern the trace.

Hello Roger,

Probably? :)
Yesterday only you on this frequency worked.

73 Andrey

New G3XBM videos on YouTube

Today I've added a couple more videos to my G3XBM YouTube Channel. They are of the Fredbox 2m AM transceiver and of the FETer 80m CW transceiver. The latter uses just 14 parts but works remarkably well. I hope to add more videos about my projects in the next few weeks.

990kms on 500kHz

My 1000kms distance target on 500kHz WSPR has still not been met, but now by just 10kms: last night I was heard quite strongly at -18dB S/N by DL4RAJ 990kms away in JN68kj. The signal report and distance now make me really believe that further really is possible with the 1mW ERP station.

3 new reporters on 500kHz

Last night I left the WSPR beacon running overnight in the hope that I'd break the 1000kms barrier at last. Again, my best report from Germany was 40kms short. However, I did get reports from 3 new stations (DL3NDR, PA0LCE and from SWL Mark in Edinburgh) overnight bringing the total number of unique reports for 500kHz WSPR to 61 plus two reports for CW QSOs. In all then 63 stations have now heard my 1mW ERP signal.

Methane release - higher than expected

From the BBC website:

"Scientists have uncovered what appears to be a further dramatic increase in the leakage of methane gas that is seeping from the Arctic seabed. Methane is about 20 times more potent than CO2 in trapping solar heat. The findings come from measurements of carbon fluxes around the north of Russia, led by Igor Semiletov from the University of Alaska at Fairbanks."

See http://newsvote.bbc.co.uk/1/hi/sci/tech/8437703.stm

G0IMG (Mike) a silent key

Yesterday I heard that G0IMG, Mike Gotch, from Saffron Walden has died. Mike used to be one of my bosses years ago at Philips. Mike became a keen 10m and 6m DXer. About a year ago he had a serious stroke and was left severely paralysed. RIP Mike.

40m WSPR with 100mW

For a change I put my WSPR beacon on 40m this afternoon and set the output power to 100mW. Within minutes there were reports coming in and some are very good. For example, -9dB S/N from a German station suggesting another 20dB attenuation (i.e. 1mW out) and the signal might still be copied. A few minutes later and there was a log from an LA 1500kms away. Incidentally, several CQs on 40m CW with 1W failed to get a response an hour earlier! I'm now trying 100mW on 30m.