"Mark D. Zacharias" wrote in message
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"Arfa Daily" wrote in message
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"Waylon" wrote in message
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My Onkyo TX 3000 stereo receiver went on the blink and I've had it in a
local
repair shop for the past 3 months. The problem with the device is this.
When you
push the on/off switch, nothing happens. Usually, once you turn it on,
it will
be about a 2 or 3 second delay, you will hear a click sound and it
powers up.
Well, that don't happen. Al the lights comes on, but that click sound
never
materializes and NO SOUND. Anybody go a clue and is 3 months typically
TOO Long
for a shop to take to repair???

I would suspect that the person who landed the job of looking at it, has
' lost his way ' a bit on it. It happens to us all sometimes, and it's
usually the slightly more obscure makes of this type of high end
equipment, that it happens on.

Basically, the failure of the unit to come on with the normal relay
click, means that the system control micro, is detecting some kind of
fault condition. This is what is being looked for by the system control
during that few seconds between you hitting the switch, and the relay
closing to complete the power up sequence. Often, it will be an output
stage problem, but this is where the fun and games can start. This kind
of problem can literally soak up hours of bench time, particularly if the
unit has discrete component output stages, and you don't have a
schematic.

Having realised that you have spent half a day, and got nowhere, the
tendency is to cast it aside to get on with some jobs that will put food
on the table. You always promise yourself that you will look at it again
on Friday when you're less stressed, and in the meantime, will try to
obtain a service manual. Unfortunately, it never works like that, and
this week turns into next week, and then next month until it becomes an
embarrassment, and you start to dread the owner ringing up about it. Any
other professionals reading this will know exactly what I'm talking
about. I'm willing to bet that every one of us has been there at some
time ...

I would suggest that you approach the shop where it is, and ask nicely
what the problem is. Suggest to them that if they are having too much of
a problem with it, that they just put it back together, and let you have
it back, as three months is not acceptable. If it's not fixed just
because they can't fix it, they shouldn't charge you anything. Most of us
who are reputable, work on a no fix no charge basis.

If the scenario is as I've described, they will probably appreciate your
direct approach and understanding. Providing that the person looking at
it is not a nonno, then as a fellow engineer, I have sympathy with him.

Arfa


I'm pretty sure this model is a bit old to have a
microprocessor-controlled protection circuit. More likely just an analog
DC detect / overcurrent detect circuit.

As far as "no fix no charge" is concerned, in my shop the initial
check-out fee is non-refundable except in extraordinary circumstances.
Three months time unable to fix might not qualify, but three months
getting a runaround would, in my opinion.

Mark Z.


Yeah, I know what you're saying, Mark. It's always a difficult one as to
whether there should be a standard charge applied to a no-go repair. I tend
to work along the lines that if it can't be fixed because there is no
service info available, and I've spent time trying to work around that fact,
then it is chargeable at the base examination rate. Likewise, if it can't be
fixed because of lack of spares. But, except in some special circumstances,
if I can't fix it simply because I personally can't get to the bottom of the
problem - and no matter how good we think we are, it happens to us all
occasionally - then I don't feel that it is justified to charge the owner
for my lack of ability in his particular case. I'm probably too soft for my
own good, but I always think that if the owner had taken it to my mate down
the road, he would have been able to fix it. ( he probably wouldn't 'cause
I'm better than him ( !! ) ) but still, the thought is always there.

The trick is to realise early on when you are beat, and not to waste so much
time, but none of us likes to admit defeat, and the answer is always just
two more voltage checks away, isn't it ... ?

And yes, you're probably right about the protect circuit. In fact now I come
to think of it, I have a dim recollection of having one of these, or a
similar vintage Onkyo, come across my bench some long time ago, with a
similar problem. It turned out to be the delay cap on the protect IC ( one
of those little 9 pin SIL things ) that was the problem. It had leaked, and
the electrolyte had attacked the timing resistor that was nearby. Cleaning
up and replacing those two items cured it.

Arfa