>Recently we had an SB-200 which suddenly refused to work. I'm not clear as
>to the exact symptoms as I wasn't there at the time. Previously the unit
>had performed flawlessly for some years after being upgraded with the entire
>suite of "Harbach mods ".
>
>While looking at it for signs of trouble I found one resistor (R7) on the
>PW-200 power supply board that was definitely "charred" ... however after
>removing it I found it still showed continuity with 900 Ohms resistance (R7
>is a 910 Ohm, 2 W). I think that this resistor provides the ALC bias
>voltage.
>
>When I removed the 572 B tubes (both GE) I noticed that one of the tubes
>had an "object" rattling around inside, completely unattached to any of the
>tube's internal structure. ... ...
What is the resistance of the filament in this tube?
tnx, Jim
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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