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From: liz@poppyrecords.invalid.invalid (Liz Tuddenham)
Newsgroups: sci.electronics.repair
Subject: Re: Is it a capacitor, is it a resistor?
Date: Sat, 16 Mar 2024 20:44:58 +0000
Organization: Poppy Records
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Chuck <chuck23@dejanews.net> wrote:

> 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 !!!
> 
> Was it a light blue Sanyo?

It was indeed!


-- 
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk