>
>On Sun, 6 Jul 97 08:36:33 -0700 Rich Measures <measures@vc.net> writes:
>>>After 25+ years that capacitor has a history of going bad. Simply
>>replace
>>>it. I replace it as a mater of course whenever I get a SB-220 in for
>>>service.
>>>
>>>73...Carl KM1H
>>>
>>25 years is pretty typical for the life span of 85=BA ...
- ok, so the option keys don't work on this server.
>>C-rated =
>>electrolytics. For even longer life, a 105=BAC-rated electrolytic =
>>would be appropriate. I would be inclined to covert the mickeymouse =
>>half-wave rectifier to a full-wave bridge whilst I had the soldering =
>>iron out.
>
>I believe the early originals were 65C rated (old brown wrapper) and
>later 221's used a blue 85C which I have yet to see go bad. I simply use
>22MF/160V 85C from Mouser...they will outlast the owner.
>Nothing wrong with the half wave rectifier in the 220...works
>fine...lasts a long time. I dont believe in making extra work for myself
>particularly for no good reason.
>
>73....Carl KM1H
>
For adding a step-start relay and high speed switching, a FWB is
indicated. Half-wave rectification causes DC to unhappily flow in the
transformer. Adding 3 more diodes and ungrounding the 80v winding is
easy/inexpensive.
Rich---
R. L. Measures, 805-386-3734, AG6K
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