I spend some time to improve the transmitter.
Low pass filter for14 MHz and 18 MHz caused too much attenuation of the signal. So I rebuild I. Using a different design and component values. Now it works fine.
CW while key was up resulted in a signals at -40 dbc. This was cause by the sideband oscillator.
I have changes the software and hardware to turn it off this oscillator during CW TX.
Now It works fine.
SSB signal sounds clean although I think it can be improved by optimizing the compression level in the speech processor.
Output for 80 and 40 meter can be improved. I may have to rebuild the low pass filters. But also the driver can be improved. At keydow it produces 3 watt on 80 meter. After a second it drops to 2 Watts. Same thing happens on 40 meter. This must be investigated.
It looks the microphone wiring picks up too much signal when an antenna is connected.
This signal is rectified and is audio then, that causes oscillation. Microphone input circuit must be adapted. adding some filters may do the trick. I have to test
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