Re: Questions on 160/80 metre AM transmitters.
I can remember back in my days as a field installer, we were installing a North West regional system going from the Cheshire Plains up to Carlisle, Storno 19 inch base stations, there were meant to be spectrally clean to -90dBc.
The customer rep armed with a spectrum analyser parked out side a site and reported to me they were not meeting the figure, I asked how he was measuring it, 'with a whip on the analyzer'. An hour later I was on site with a big notch filter to remove the fundamental from the input, harmonics were then better than spec. I do think you are correct in that to get a clean signal I have to have a clean drive to the PA.
I will look at having the VFO run at 80m switchable if possible, or just leave it as a Top band set.
I can have a play with it as I still have to do NET, STBY and TX switching at some point on it, I am looking for a small ish rotary that has a widish wiper to give 3 active positions. Think I will head to Lincoln in a week's time to the rally.
Other then that, it can still make a good pantry TX just off the bulb and keeps the useable RF within the house.
Adrian
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