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Old 23rd Aug 2019, 10:23 pm   #14
Herald1360
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Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 16,535
Default Re: ALBA model 70 Radiogram nothing happening at gram socket.

Whatever you connect to the gram input has to have dc continuity (like a magnetic pickup's coil) or else the biassing for V3 will be all over the place with its grid floating......


Could this be the problem?


Try connecting a 100k resistor across the gram input and coupling the signal via a 1u capacitor and see what happens.
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