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 Return to top of page · Post #: 1 · Written at 12:36:59 AM on 3 October 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1407

The model number escapes me at the moment.
The output transformer was open circuit, the original had the usual two input wires but had three output wires, one of which went to ground along with the speaker wire and the third one went to a 25μF electro which was connected to a valve ( negative feedback?), of cause the new transformer only had two output wires, so how would I wire it up? , does the third wire somehow connect to one of the others? , I get sound but low volume. Will try and find the model number.


 
 Return to top of page · Post #: 2 · Written at 12:51:48 AM on 3 October 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1407


 
 Return to top of page · Post #: 3 · Written at 7:49:43 AM on 3 October 2019.
BurntOutElectronics's Gravatar
 Location: Melbourne, VIC
 Member since 2 October 2019
 Member #: 2392
 Postcount: 15

I mean you could try connecting the electrolytic to one of the other two wires and see how much proformance is gained. Did the centre tap go to ground?


 
 Return to top of page · Post #: 4 · Written at 11:18:22 AM on 3 October 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 3711

I think one needs a number: Some of the amplifiers using 6BM8 and such were "Ultra Linear" And the three wires were the primary side. 25μF & low voltage sounds like cathode.

Thinking aloud not, the place for negative feed back.


 
 Return to top of page · Post #: 5 · Written at 7:41:40 PM on 3 October 2019.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 1407

Yes the centretap went to ground +speaker wire.


 
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