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Bill
 
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Hi Michael
You could have use 2SA1943/2SC5200 for the above output transistors
these are direct replacements for
for your information these are available at www.electronica-usa.com
B. Poulos

wrote:
Thanks to the new Google's "feature" preventing me from adding to
the original thread (no "reply" allowed after 30 days) I'll have
to start a new one.

Around May 19, I posted the above request for subs for outputs for
the Pioneer VSX-454 surround receiver. Jurb gave a technique for
replacing the outputs with 220 ohm resistors across the B-E pads
to check the drivers without blowing up more output transistors.
I tried his technique, and it worked. No DC on output, tried
headphone jack. I have an old pair of 600 ohm Sennheisers, so no
problem driving them. I was surprised how alike the two channels
sounded, considering one channel was missing its output stage.

Anyway, I ordered the new transistors from B&D. They had Toshiba
2SC3281s but a sub for the 2SA1302. The hardest part was then
getting the 2 flameproof resistors & fuse I needed, as B&D
didn't sell them and I no longer had enough to meet MCM's minimum
order. I needed an 8 amp 5x20 mm fuse, the biggest I could find
was 6.3 amp at Radio Shack, and I got the resistors at an
electronic/industrial surplus store. All the 150 ohm flameproofs
they had were 1 watts, luckily enough room on the board to fit them
- originals were 1/4 W. After seeing them light up orange when
the amp first blew, I wasn't going to use regular carbons in there.

The receiver's been working now for about 3 weeks - I just wanted to
make sure the repair held up before posting this follow up.


Mike
WB2M