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THE AM BULLETIN BOARD => Technical Forum => Topic started by: K1JOS on May 07, 2024, 10:04:02 AM



Title: KWS-1 Tracing Signal Advice
Post by: K1JOS on May 07, 2024, 10:04:02 AM
My KWS-1 generally works well but requires a very high knob setting on Carrier Level (9 /10) to get correct drive for tuning/loading in CW to full output. All resistance/voltage checks closely match the manual.  I have isolated the problem as signal loss to the 6CL6 driver pair grids.  I checked PTO output which is very good.  So, problem is somewhere between the 250kc oscillator and 2nd amplifier (V203).  I tried to follow the signal in CAL emission mode from the osc through each stage with a scope 10x probe (10M/11pF) but it loads down the circuit.  It may be my technique of using tube extenders on two tubes between each stage.  I tried to get under the chassis but the stage compartments in the KWS-1 are just too tight to get a scope probe onto tube pins or the deeply embedded domino mica caps.  Any suggestions for cobbling together a better scope probe to do the job?

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