I fixed the problem with the RIT. It was wired incorrectly.
The TX/Rx leds now work for both 80 and 20 meter. These too were wired incorrectly.
Somehow I made shortcircuit somewhere. This blew a BD137 power transistor.
Fortunately I had a few more in the junk box.
At 80 meters I was able to get a bit more than 10 Watts CW. SSB however was at 3 Watt max.
I have checked all circuits. They seem ok. I fixed it by making a small mar 4 based amplifier. Now I get 10 Watt PEP out. Current is 3 Ampere at 13.8 Volt
On 20 meter it does not work that well. Output is 3 Watt PEP. The input signal is according to spec.
Looking at the signal levels in the PA module it seems that I cannot input more signal.
More signal will cause an distorted output signal. It should be possible to get 10 watts at 20 meter though. I have another power module without transistors. I will try 27 MHZ transistors instead of the BD137. I hope that does the trick.
One of the remaining problems is the enclosure. I need to make a cover for the top left right and the bottom. I hope I can get some aluminum cheap.
Vraagje, waar heb je die MAR versterker tussen gezet. Direct achter de 9MHz balansmodualator of verder op in het circuit Ik ben zo'n ding aan het restaureren. De microfoontrap kan je niet eindeloos opschroeven meer komt er toch niet uit behalve vervorming. Wil de balansmodulator uitrusten met moderne shottkeydiodes, misschien ook nog een verbetering.
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