One channel on stereo amp blows filter cap on negative rail
Tiger Luck wrote:
snip
The grounds are intact. By that I mean to say that point in the CB
where
electrolytic caps C312 and C313 are grounded is continuous with the
ground at the
power supply filter caps. Chassis is the same. All points which are
supposed to be
grounded are continuous as read by an ohm meter.
Those little 100uF caps are _not_ the main 'lytics. The mains would
likely be 1000uF to 10000uF (or possibly even more) and be located
near the main bridge rectifier - which is on the _rest_ of the
schematic along with the power transformer.. I think you'll find the
main negative bus 'lytic to be open or dried out so that you're
putting LOTS of ripple current on those littlle 100uF caps. Those
100uF caps are just local 'clean up' caps and can't handle the load.
G²
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