magnatone 213 finished - vibrato doesn't work

[dinkotom]

finished it yesterday, sounds fine, but no vibrato What are the first things to check? I already swapped few tubes, tried Workman FS 1205, FS 1226 and Zenith 63-10281 varistors. Any help appreciated.
Thanks,
Dinko

[Robert M. Martinelli]

Hi,
if the vibrato doesn't work either your osc tube is not working or the signal does not make it through.

If you have a scope you can check the osc waveform, if you don't, try to measure the DC voltage across the 270K osc anode resistor, the voltage should swing some in sync with the osc speed.

If the osc works, try to follow the signal path ( e.g. the vibrato cancel jack could be shorted to ground )...

HTH

Best regards

Bob

[dinkotom]

Fixed it - I had soldered a 2.2nf cap to speed pot instead of 22nf - works fine now!