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Old 10th Nov 2021, 10:51 am   #23
Phantomrose1999
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Join Date: Mar 2008
Location: Melbourne, Victoria, Australia
Posts: 261
Default Re: Grundig TK27 - Low audio output

Some good news, finally got time to play again today, and i dropped the PCB down and measured all voltages around the EL95, and they were all a little high, but very close to the specs..

So while it the PCB was down, i touched the head signal wires and there was a loud buzz much louder than then original low volume problem...hmmmm

So while it was vertical, i managed to get a tape on, hold the reels from falling off and press play !! and WOW ! it was normal, with enough volume to cause heavy distortion when turned up.. So this meant when the PCB was down it played loudly.

Next i put just the PCB back and it still played fine, then started putting the metal shield on and my friend noticed some spacers were longer then others and i have them randomly.

So, we put the long spacers on the righ, and the shorter spacers on the left, and did up all the screws and its playing like it left the factory !!!

Seems i had fixed the original problem of low voltage with the missing transformer wire, and putting the PCB spacers incorrectly also caused low volume.. maybe it was oscillating and that killed the audio volume.. I was going to put a CRO on it, but no needed now.

It puts out around 2.5W like most of the EL95 units and i think it will sound good with an external speaker.

Next will be a record test.. then it gets posted to youtube..ha. (if it can record that is)
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