Tram D201 meter spike in ssb transmit

[klj2497]

I followed the spike when i key up on ssb from v701 pin #4. mod. B+ to the orange wire coming from the t600 transformer. it also spikes on the white wire from the transformer. The resistors dont seem to stop the spike going to v701 pin#4. Im wondering if the t600 is bad, or can something else be wrong.

 

[klj2497]

I checked my other tram d201 it also has a little spike on ssb keyup. I noticed when i purchased the problem tram that the L 700 air duct, had been cut and resoldered missing 2 coils. When i looked online i found a picture of the mod on another post . I think it supposed to increase ssb. Im wondering if this could cause the excessive spike on keyup.

 

[klj2497]

Im still trying to chase this down. have replaced the relay, the modulation transformer, v700, and v701. I still have a stray shock of output, before the little spike in voltage that happens at keyup.

 

[Dmans]

klj2497,
Have you changed all of the electrolytic capacitors in this unit?
There is typically a low current draw when in receive mode. When transmitting there is an instant demand for more current/voltage to the output tubes and modulator section. Sounds like a weak or lower than normal value electrolytic capacitor somewhere.

73
David

 

[klj2497]

I did change all of the can capacitors when i purchase a capacitor, and a resistor kit from ebay awhile back, I also put in new c624 and c5 capacitors. I wonder if one of them may be bad, or it may be one of the old caps that wasnt in the kit.