I have a loud buzzing on key down at times. It is not transmitting then. If I power off and on it usually goes away and sounds ok on my receiver. The finals have been replaced and power is about 4.5 watts. SWR is about 1.4 and battery is 12v. It’s random. It’s easier to fix if something stays broken. Microcontroller issue? I might have a spare but this was built several years ago. The fact that it just makes a loud buzzing sidetone with no iambic keying even though it’s selected puzzles me. After rebooting it usually works. Another transistor in the keying circuit questionable? Waveforms looked ok. May need to look again.
73s John N4HNO
