Wally wrote:
I've got a dead Mission Cyrus Two amp, which was inherited from a
mate a couple of years ago. On looking inside, it appears that there
are two TO220 packages which have had the tops blown off them, along
with an 8-pin IC. The part numbers, as best I can make out, are...

TDB 0137 SP
LM 317 SP
LF 353 DP

The 317 is a voltage regulator, and I'm guessing that the 0137 is the
negative equivalent of the 317. Does that sound right? I think the
353 is an op-amp. The resistors adjacent to the TO220 packages still
produce readings, so I'm assuming that they're okay. I haven't
powered it up to see if the PSU is okay, and I haven't tested any
other components (like o/p trannies).

I'm wondering if changing the blown devices might just effect a
repair. Before I get the soldering iron out, does anyone have a
schematic for this amp, or know where I can get one?

You can replace the TDB with the easier to find LM337. It soulds like a
nasty short somehwere to blow the regulators or more likly giving them a
rather high voltage to try and regulate. I would give the PSU a good
checking over before you blow another pair! The op-amp would require a +ve
and -ve supply so probably died before the regulator gave up!

Will