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Re: 1959 Fender Bassman 5F6-A Power output??'s

7/6/2004 5:44 PM
Wild Bill	Re: 1959 Fender Bassman 5F6-A Power output??'s What Speed said... As well, it's cheap insurance to replace all the bypass caps across the cathode resistors in the preamp stages. These often get forgotten but they are electrolytics after all and will dry up over the years just like their bigger cousins in the filter section. When they dry up the sneaky thing is that they don't short, they just sit there and do nothing! What they are supposed to do of course is provide an AC signal bypass. With no bypass action the gain of the stage is much reduced, which might account for the low power you measure. Everything looks good but there's insufficient drive coming from the preamp. .02 ---Wild Bill

7/6/2004 5:44 PM

Wild Bill

Re: 1959 Fender Bassman 5F6-A Power output??'s

What Speed said...

As well, it's cheap insurance to replace all the bypass caps across the cathode resistors in the preamp stages. These often get forgotten but they are electrolytics after all and will dry up over the years just like their bigger cousins in the filter section.

When they dry up the sneaky thing is that they don't short, they just sit there and do nothing! What they are supposed to do of course is provide an AC signal bypass. With no bypass action the gain of the stage is much reduced, which might account for the low power you measure. Everything looks good but there's insufficient drive coming from the preamp.

.02

---Wild Bill

Replies:

Paul Bamberg Thanks guys for the timely response... -- 7/6/2004 7:18 PM