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eu.thundernews.com
Posted: Thu May 01, 2008 3:45 pm
Guest
Hi, I am planning to restore the above as I can get hold of the components.
The radio receives lw/mw and 6 sw bands.

It was working ok and then the volume suddenly dropped to about half that it
should be, the potts have been cleaned and are not noisy.

The radio picks up all the channels it did previously but it is quiet and
turning the volume pott up or down does pretty much nothing.

Could anyone point me in the general direction of which component/s to look
for as the culprit/s?

Any help would be massively appreciated.

I will post the schematic on alt.binaries.schematics.electronic entitled
'Pye P35 Schematic'

Thanks for any help guys.
Don Bruder
Posted: Thu May 01, 2008 4:44 pm
Guest
In article <c_pSj.1458$Cr1.1372@newsfe18.ams2>,
"eu.thundernews.com" <blib@blop.flob> wrote:

Quote:
It was working ok and then the volume suddenly dropped to about half that it
should be, the potts have been cleaned and are not noisy.

The radio picks up all the channels it did previously but it is quiet and
turning the volume pott up or down does pretty much nothing.

Could anyone point me in the general direction of which component/s to look
for as the culprit/s?

Based on what you're describing, the first place I'd look would be the
heater of the output amp tube. Betcha a nickel the filament died...

--
Don Bruder - dakidd@sonic.net - If your "From:" address isn't on my whitelist,
or the subject of the message doesn't contain the exact text "PopperAndShadow"
somewhere, any message sent to this address will go in the garbage without my
ever knowing it arrived. Sorry... <http://www.sonic.net/~dakidd> for more info
Stephen J. Rush
Posted: Thu May 01, 2008 8:37 pm
Guest
On Thu, 01 May 2008 14:44:40 -0700, Don Bruder wrote:

Quote:
In article <c_pSj.1458$Cr1.1372@newsfe18.ams2>,
"eu.thundernews.com" <blib@blop.flob> wrote:

It was working ok and then the volume suddenly dropped to about half
that it should be, the potts have been cleaned and are not noisy.

The radio picks up all the channels it did previously but it is quiet
and turning the volume pott up or down does pretty much nothing.

Could anyone point me in the general direction of which component/s to
look for as the culprit/s?

Based on what you're describing, the first place I'd look would be the
heater of the output amp tube. Betcha a nickel the filament died...

If the audio output tube died, you'd get no sound at all, not about half-
volume. It's not uncommon for old carbon resistors to increase in
value. Coupling capacitors develop leaks, but that usually causes
obvious distortion. The nice thing about troublshooting tube gear is
that you can measure resistors in-circuit (With the power off!). If you
have the schematic, it probably gives DC voltages; knowing which voltage
is out of spec you can usually deduce which component might be bad.
 
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