Hello all. After an absence of well over a year I'm now back on LF with a rebuilt transmitter (similar to G0MRF type) and 250 Watts reliably. Antenna tested out - still OK ! - but as its only a 7m hi
As I've been away from this reflector for a year and lost touch with the LF scene, are there preferred freqs for any mode - apart that is from sitting between Loran spurs. In other words is there a B
PSK08 is a modification to the PSK31 data waveform, now very popular on HF, but operating at a quarter of the signalling rate, ie. 7.8 Bits/s. I modified G3PLX's software for the Motorola 56002EVM bo
Now I know a few copies of PSK08 are out there I'll transmit this evening around 2000z. Frequency will be 137.500 +/- 0.5 Hz, chosen after careful consulation with this group :-|) Probably won't list
I have a number of, quote, "High Voltage" reed relays. They were made by FR Electronics (as was) and I seem to recall are specified to something like 10kV and 1 Amp which means they may well work hig
Managed to find six spare reed relays that look as if they may be suitable for LF antenna switching . The reed connection points are well separated from the coil connections by about 10mm in air with
A few people have commented to me about the annoying attachment that appears at the end of messages from this account. Some are even woried about its implications to themselves ! It is placed there b
I am particularly interested in these low frequencies, especially as 137 and 73 have become just DXCC and CW operators bands. I was considering applying to our licensing agency for a narrow allocatio
It would be unfortunate to limit ourselves to just use of these two relatively simple pieces of DSP software which at the end of the day are really just narrowband power detectors in not that narrow
Moving from LF to MF for a bit, here's a problem for the topband operators and loading coil winders. At the weekend I made a loading coil to resonate the LF Tee antenna on topband. 34uH was needed an
Well, Gamal and Paul between them hit on the solution. It definitely appears to be proximity effect causing extra losses for the Litz wound coil. I re-measured both at 80kHz and the Litz one came out
If anyone wants to experiment with simple DSP techniques beyong just plugging in Gram etc, or even wants to try some programming without having to learn Windows API calls and how to use the soundcard
I have not played with Spectran yet, but on the question of dot length...... The optimum dot will depend on the FFT and integration time of the software. Ideally the dot length will be a multiple of
Don't joke ! I have seen a genuine proposal / request for licence (and it was not an April fool) for a spread spectrum radio system that transmits data as very fast short pulses over a wide band to r
Andy G4JNT -- The Information contained in this E-Mail and any subsequent correspondence is private and is intended solely for the intended recipient(s). For those other than the recipient any disclo
Last night I tried to make a Dopplergram trace of a carrier transmitted from Marco in a bandwidth of 0.12 Hz. On looking at the plot this morning I'm not too sure what to make of it an whether the re
I got the impression that carrier has only appeared recently - withn the last couple of months anyway, but my memory is probably fading with age ! I spotted it since It was sitting only a few 10s of
I was receiving Marco's carrier during the night tests at 20 - 30dB above noise in a 2mHz bandwidth at a distance of 927km. Daytime was 10 - 15dB lower. In a Spectran bandwidth of 0.03 Hz that will c
I think most modern transceivers derive all their internal frequencies from one master oscillator. The IC746 uses a 30 MHz device which at extra cost can be replaced by a small 1-2ppm ovenned oscilla
