In article , Dave Plowman (News)
wrote:
I've never seen an AM8/16 so have no idea what changes the BBC people
may have made. I can't tell if the 'quawk' is due to a protection
circuit rattling on and off, bursts of RF instability, or what. Might
be fixable by a bigger output inductor or a cap in just the right
place. But where?...

Thought I'd made it fairly clear. If you remove the power to the
crossover PCB while leaving the amp powered up, you get the squawk.
Leave the power off that PCB, and the Quad part powers up and off
normally.

OK. Then maybe a circuit on the *input* of the 405 that duplicates what it
sees from the output mute on the 34 might help? IIRC this just clamps the
signal line to ground using a bipolar.

Jim

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