Andy et al
Is that 6dB down on mean power ? As PSK31 has a peak to mean ratio of
exactly 3dB I suspect the extra power reduction is to get the transmitter
into a suitable linear region.
It's a different TX, a PA strip from the transverter output of the IC735
which I have modified to give an output down there. The PA is a hybrid of
David's design and my topband FET linear with a pair of IXFH75N10 at 24V. It
produces 250W key-down (PEP) and obviously shows less average when sending
PSK31 due to the holes in it! Do you intend to use BPSK or QPSK? Any other
parameters I should set? I have copied several stations on 80 so the RX
works OK. I will put out some calls down the bottom of the band, about
136.2, at around 8pm for the rest of the week. I will listen co-channel.
Any reports gratefully received.
73, Dave G3YXM.
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