Problem: Sansui 9090 Protector Light Flashing Red
Sorry, just get a bit weary of the clueless uninitiated who come onto this
group, wanting to know "what always goes wrong" and too cheap to pay to fix
the stuff. They are much more likely to damage the equipment or create a
safety hazard, though the concept of a "Darwin Award Winning Moment" does
appeal to me as it pertains to these people.
Mark Z.
"Rep" wrote in message
om...
Message like the one you have below implies that you have way too much
lead in your system! You forgot to include wear a mask, do your
soldering on a ventilated system and wash your hands after.
"Mark D. Zacharias" wrote in message
. earthlink.net...
OK, I've been waiting to post this. Here it goes:
First, learn some electronic theory and fundamentals, so that you will
not
injure or kill yourself, and so you will know a bad part when you find
one.
It is critically important to understand theory of operation and
signal-flow
if you are to have any hope of repairing most equipment.
Buy a relatively inexpensive digital multimeter, probably at Radio
Shack.
An oscilloscope would also be most useful; a decent used one can usually
be
found for 100.00 or less.
Learn the appropriate safety considerations for using the tester and
'scope.
There are special considerations for working on most televisions and
other
equipment not using a built-in isolation transformer. Most servicers use
an
isolation transformer for any AC-powered unit under test.
Learn how to use the multimeter to measure resistance, voltage, and
current.
Learn how to use the oscilloscope to observe and analyze waveforms.
Buy a soldering iron, solder, and desoldering equipment.
Learn how to solder and unsolder without damaging the circuit board.
Find a source for replacement parts. Most suppliers have about a 15.00
minimum order.
Order the replacement parts and install them.
Clean the circuit board where you were soldering. Treat the job as if it
were going to be inspected afterwards and graded for neatness.
Visually inspect the piece for any other problems or safety issues.
NOTE:
You are personally responsible for any safety problems you cause, or
those
which you
SHOULD have noticed and failed to correct. So if you work on a TV and it
burns down your friend's house in the middle of the night
because
of something you missed or that you caused, they can sue you, even years
later.
At this point you can just replace a blown fuse, if any, plug the unit
in,
and hope your new parts don't just fail again because you missed
something
or installed a part incorrectly. (Or you could use an AC variac to bring
up
the line voltage slowly while measuring voltages etc. MCM sells one for
90.00)
Check for normal operation. Watch for any signs of overheating, hum,
smoke,
etc and be prepared to shut down quickly.
Test for longer-term operational stability, check for neatness of lead
dress, re-assemble the rest of the way, making sure not to pinch any
wires
etc. Make up your mind to re-assemble the piece exactly as it was. If
there'
s screws left over, you did a sloppy job.
Final test the piece, and satisfy yourself that there is no possibility
of
leakage current between any exposed metal and the AC line. There are
several
ways of doing this. Please refer to the manufacturers' service data or
your
textbooks.
Decide how to politely tell friends, family, freeloaders and cheapskates
that you must charge appropriately for your work.
Welcome to the exciting world of electronics repair.
Mark Z.
"Sofie" wrote in message
...
George:
Based on your original posting, a manual and a schematic are NOT going
to
be
much help to you...... it will only be of most use to an experienced
and
knowledgeable tech with the proper test equipment, tools, replacement
parts,
etc. In fact, most techs will repair this kind of problem without
the
manual and schematic.
The Sansui 9090 is a very nice old and powerful receiver and is worth
repairing. Take it to a repair shop BEFORE any failed, botched or
aborted
home repair attempts and at the very least get a repair cost estimate
so
you
can make an INTELLIGENT repair decision with facts instead of internet
guesses.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------------
Today I turned on the Sansui 9090 and the flashing red protector
light
next to
the power button continuously flashed and the stereo never did go
on.
The tuner
seemed to be picking up signals, as evidenced by the signal
meter,
but
the
sound output meters registered zero and no sound came from the
speakers.
Usually
the light flashes red for a few seconds, turns green and then the
tuner
and
stereo activates. Can someone tell me what the cause might be and
if
there is a
simple fix I don't have a manual for the unit, and have no idea
what
the protector light is
for. Can someone tell me where to obtain a manual?
Thanks.
George
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