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previous: Mike O The tremolo on my 68 SR does not se... -- 1/22/2000 8:54 AM View Thread

Re: Tremolo on SFSR

1/22/2000 1:00 PM
Randy Jamz
Re: Tremolo on SFSR
'Fixing' an amplifier via email ain't easy, but let me give you a quick list of things you can do to not only get on the right track, but be half way along!  
1)Resolder everything that can't outrun you.  
2)Place an analog voltmeter on the tremolo tube's plate.  
3)With the tremolo 'on', your voltmeter should 'swing'.  
4)If you ain't swinging, take a decade box and bridge every cap and resistor in the tremolo feedback circuit until the plate voltage shows a swing. You should be able to make the swing faster and slower with the 'Speed' control.  
5)Once you are swinging, as long as the opto-isolator is OK, your tremolo should be fine. Poor lead layout may cause chirping. Hope this helps, good luck!