"RDC" wrote in message
...

I have an RX-570 here that keeps popping the outputs and have no clue
where the SM Transistors are to defeat the BLOW Line in it. According
to another post I read, Q7401 and Q7406 are the SMTs in question, but
they're not on the amp boards, are invisible or I'm going blind. The
entire amp module is brand new, so you can imagine I was pretty
suprised (enraged really) when I fired it back up and it killed the
thing. I had a 100w light bulb in there to keep it from self
destructing as well, but it didn't help.

I want to rule the entire amp module out, since it was new and still
got toasted. I replaced the outputs and the 220ohm resistors are all
still good on it. But now really have no clue where to start looking
externally for whatever is kicking the "protection circuit" (term used
very loosley) on. Every other one I've ever messed with had open
resistors or shot outputs and that repair alone fixed them up, but this
things deciding to be a nightmare. If you have any ideas or info I thank
you a ton in advance.


--
RDC

The surface-mounts are there - they are just hard to find. A nagnifying
glass helps to find the board markings.
These units can be blown by a bad cassette motor or any power supply voltage
being low.
When you find 7401 and 7406, short the E-B junctions.

Mark Z.