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From: legg <legg@nospam.magma.ca>
Newsgroups: sci.electronics.repair
Subject: Re: Is it a capacitor, is it a resistor?
Date: Fri, 15 Mar 2024 10:23:18 -0400
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On Thu, 14 Mar 2024 20:56:32 +0000, liz@poppyrecords.invalid.invalid
(Liz Tuddenham) wrote:

>I was asked to repair a Pioneer QX-949 quadraphonic tuner/amplifier.  It
>is a complex beast and one channel had gone down to almost nothing.
>Luckily the service sheet was available and I traced the fault to the
>board which houses the tone controls and filters.
>
>The gain is in two stages with the tone controls around the second
>stage.  On one of the channels, the voltages on the single transistor
>for that stage were all wrong.  After lifting the transistor off the
>board, it became apparent that the base bias was far too high and the
>finger of suspicion pointed to the inter-stage coupling capacitor
>feeding in leakage current from the preceding stage.
>
>I tested the capacitor, which was marked "4.7".  It read exactly 4.7k in
>both directions on an ohm-meter !!!


Used to keep a special box for spectacularly wrong parts, but never 
found a situation where their re-use was justified, even as a joke.

Everybody takes themselves so seriously these days. At least each 
part had a story behind it . . . .

RL