I know I said I wouldn't do anymore serious testing until I'd built a new PC, but I just couldn't help myself. Over the last few days I have been active on 20m with reasonable success.

After experimenting with different settings on the computer soundcard and the audio levels on my interface, I came to the conclusion that running the sound output from the PC at 100% for both the master volume and PCM volume was a bad idea.

I can't say why this didn't occur to me before especially considering I'd noticed audio distortion on other computers when listening to music with the levels at 100% - I'd always reduce them slightly with significant improvement. So it was, that after various tests I came to settle on the master volume at 90% and the PCM fader at approximately 50-60%. Further adjustments would then be made at the soundcard interface.

The other conclusion I came to - and this is almost certainly ludicrously obvious to all seasoned PSK operators out there - is that adjustments to the audio level need to be made after each change in frequency made on the computer. The higher the audio tones (higher frequencies) the louder the audio going in to the radio needs to be. When changing to lower frequencies, the audio volume needs to be reduced to maintain the same power level.

Now I've made these discoveries, I've had a lot more fun! Since I had today to myself, I decided to make it a radio day and have been pretty much stuck to the keyboard calling CQ and answering the calls of others. I'm still limited to around 10w of power since higher levels continue to interfere with the keyboard; but - and here is another revelation that will be obvious to the old-timers - power isn't everything.

To give an example of the success I have had today, I have made contacts with operators in Spain, Sweden, Italy, Poland, Slovakia, Ukraine and Russia. Perhaps that doesn't sound too remarkable, but considering my balcony mounted whip aerial I'm very pleased. To top it off though, according to the PSKReporter map, which I monitored throughout the day, my signal was reported as being heard in Canada! That is something I'm really pleased about.

What I do find strange though is this keyboard interference. All day I have been transmitting with 10w of power - sometimes creeping up to 14w. The keyboard has been fine. A key may occasionally not respond but it was easily workable. However, about half an hour ago when working RX6BH in Russia, the keys became very unresponsive making typing during transmission a nightmare - it was slower than transmission rate of PSK31! I'm not sure why this would be. Nothing had changed. The power level was peaking at 10w initially, and I even reduced it slightly to no effect.

Actually, I'm wrong. Something had changed. I'd switched on the lights in the flat. Could that be what makes a difference?

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Tags: amateur radio, psk31