>
>At 06:04 AM 10/2/2001 -0700, 2 wrote:
>
>> >Tom gets the troubleshooting prize for this problem.
>>
>>// Agreed
>>
>> >After pulling the caps,
>> >I checked the equalizing/bleeder resistors and found one open! It looks
>> >absolutely perfect, no signs of physical damage such as heat, cracks or
>> >scrapes. I'll need to get a replacement, then see if the cap is damaged
>> >beyond use. It's doubtful at best.
>
>
>Thinking back a number of years, I had exactly the same experience with the
>equalizers in my Viewstar amp. Two of them were open, with absolutely no
>visual evidence that anything was wrong. These were 10 watt Ohmite Brown
>Devils
// An apt name.
>- decent quality wirewounds by most standards. The resistors
>"looked" like new. In my case, the capacitors were fine despite the open
>resistors.
>
// If this situation had gone on for long, two of the filter capacitors
would have been long gone.
cheers, Phil
>
>> >
>> >Thanks again for all the feedback. It's been an education beyond the
>> initial
>> >problem.
>> >
>>// Unreliability is why we do not proffer wire-wound resistors for
>>electrolytic capacitor equalizer/bleeder service. Although lower value
>>wire-wound resistors are fairly reliable, as you have apparently
>>discovered, such is not the case with higher-value units.
>>- My guess is that the capacitor that had the open bleeder has white
>>deposits around the pressure vent. and/or shows higher leakage @450v.
>>Replacing the entire string of capacitors with new, 105ºC units might be
>>best. I would also replace the wire-wound equalizer resistors with MOF
>>resistors because they are more stable & more reliable. /sources:
>>Mouser Electronics -- 800.346.6873. Digikey -- 800.344.4539/
>>
>>cheers, Mark
>>
>>- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
>>end
>>
>>
>>--
>>FAQ on WWW: http://www.contesting.com/FAQ/amps
>>Submissions: amps@contesting.com
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>>Problems: owner-amps@contesting.com
>
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
end
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