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Old 11th Nov 2021, 7:06 am   #27
Phantomrose1999
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Join Date: Mar 2008
Location: Melbourne, Victoria, Australia
Posts: 289
Default Re: Grundig TK27 - Low audio output

Quote:
Originally Posted by DMcMahon View Post
Voltage measurements (DVM) for comparison on my TK 27L were :-

Main HT +261V (Playback), +268V (Record) with 100Hz (10mS) ripple 4.5V p-p

HT on other side of filter resistor R17 (2.7K) = +236V, 40mV ripple.

Main HT with EL95 removed +282V

Main HT with no valves fitted +294V

David
While checking the lack of an oscillator with my CRO, i measured the following ripple as well.

HT straight from the rectifier, 5.52v, about 100hz.
HT 120mV P-P after the filter resistor, also about 100hz


Back to chasing why no oscillator..
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