On Fri, 11 Jun 2010 11:06:13 -0500, Jim Yanik wrote:

did you check the ESR of the electrolytics,particularly those around
your IC?

All checked good, but were replaced anyway (they were off-brand Chinese
things that I've seen fail in the past).

Thus far I've replaced:
TEA1522
Optocoupler
Shunt regulator
One shorted diode in the 5V loop. Looked good on the meter in-circuit,
took it out of circuit and my DMM and the Atlas DCA reported it as dead-
shorted.

I've checked the resistors around the shunt regulator and the TEA,
they're fine. All the other stuff around the TEA looks good, but still
noting... "Beam me up, Scotty, there's no life out here."

I'm getting sorely tempted to disconnect the secondary diodes for all but
the 5V rail, then reconnect them one by one...

--
Phil.

http://www.philpem.me.uk/
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