It is the solder connections - the new ic just runs a bit cooler. Part of
Pioneer's fix was to add a special "socket" for the new IC, but there were
problems with this.

Desoldering the IC for replacement is a problem. I use a Denon desoldering
tool, which I have discovered is no good for this job. The required
desoldering equipment is surely not cost-effective for most of us.

Mark Z.

--
Please reply only to Group. I regret this is necessary. Viruses and spam
have rendered my regular e-mail address useless.


"Ampdoc" wrote in message
. ..
You need to replace IC9374 and change the position of the 2 zero-ohm
resistors. It's not a bad solder connection, it's a faulty ROM, the data
in
the ROM tells the DSP IC what to do. The new part is a flash EEPROM, thus
the need to change the jumper resistors. Sometimes resoldering makes the
ROM
work a little while, but it's due to the heat. You can warm up the IC with
a
heat gun and produce the same effect. My last couple of posts on this unit
didn't show up, so here's another try.


--
Jammy Harbin
J & J Electronics, Inc.
227 S. 4th St.
Selmer, TN 38375
731-645-3311
"Jeff" wrote in message
...
Mark,

Thanks for the quick reply!

After I posted my earlier message, I found a discussion in the newsgroup
about the VSX-29TX, which is basically the same model. I think you
helped
whoever asked back then also...

Anyway, that discussion set me on the right course (check the DSP
board).
I
discovered that there is audio present at the board's input, but not its
output. Fortunately, Pioneer did a nice job silk screening the board --
all
the connectors are labeled in a way that makes sense.

I poked around and managed to get the thing to work a few times, in less
than the usual warm-up time. I then looked at the address (or data --
I
don't know) pins on the large PLCC part with my scope (is this the SRAM?
It's Toshiba and marked like a memory) and noticed that it looked like
the
DSP is resetting a few times per second, rather than executing
continuously
as it should.

If the PLCC device is indeed the SRAM to which you're referring, I can
probably resolder it. If it's the DSP, then I'm in trouble! I don't
think
I have any chance resoldering that.

Thanks again!

Jeff

"Mark D. Zacharias" wrote in message
...
There is a known problem on these - a RAM IC needs resoldering. Expect
a
recurrence after a year or so. Not for the novice - the foil runs at
the
IC
are too easily damaged. It is on the DSP board, but the board is no
longer
available - since Pioneer went through all of them for this problem.
For
a
while Pioneer was exchanging the receiver for a newer model - but I'm
pretty
sure that program would have ended by now.

Mark Z.

--
Please reply only to Group. I regret this is necessary. Viruses and
spam
have rendered my regular e-mail address useless.


"Jeff" wrote in message
...
I have a Pioneer VSX-27TX receiver that works fine in all respects
except
that it takes about 20 minutes before audio can be heard from any of
the
outputs (main or surround.) During the 20 minute "warm-up", the
display
is
active and all control functions of the receiver seem to work. I
can
use
the tuner, select inputs, enable/disable surround modes, use the
remote
control, etc. Also, signal is present at the tape output during
this
time,
but not at the preamp outputs.

Once 20 minutes (or so) has passed, the audio almost suddenly starts
playing.

Whatever is wrong, it seems to be temperature related, as the
"warm-up"
time
is shorter if I cycle power after the receiver has been on for a
while.

Has anyone seen similar behavior from this unit? Any tips as to
what
might
be wrong? Does anyone have a schematic for this model?

Thanks,

Jeff