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Vintage threads from the first ten years

previous: carl 74 sfdr converted to bf. Has the c... -- 1/16/2000 4:36 AM

Re: SFDR ticking

1/17/2000 8:46 AM
Steve A.	Re: SFDR ticking Carl: Dan Torres quoted from Fender Service Bulletin #9 in one of his VG articles: In addition to redressing the vibrato leads away from the tone controls and filter leads, a 0.01uF/600v cap to ground from the plate of the second vibrato stage should cure the ticking. This cap is soldered to the junction between the 10M screen resistor and the opto, and is grounded with that stage's cathode resistor and bypass cap. (An earlier fix from Fender was to put a cap across the 10M screen resistor; that cap should be removed.) The bulletin also suggests that you "bunch together" the leads going to the vibrato tube. Hope that helps! Steve Ahola

1/17/2000 8:46 AM

Steve A.

Re: SFDR ticking

Carl:

Dan Torres quoted from Fender Service Bulletin #9 in one of his VG articles: In addition to redressing the vibrato leads away from the tone controls and filter leads, a 0.01uF/600v cap to ground from the plate of the second vibrato stage should cure the ticking. This cap is soldered to the junction between the 10M screen resistor and the opto, and is grounded with that stage's cathode resistor and bypass cap. (An earlier fix from Fender was to put a cap across the 10M screen resistor; that cap should be removed.) The bulletin also suggests that you "bunch together" the leads going to the vibrato tube.

Hope that helps!

Steve Ahola