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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

How to check output transformers ?

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I've been given a pair of output transformers by a friend. Is there a quite easy way to test them ? I've no oscillope at home, just a dmm. All procedures I found on the web take for granted that the xformers are still on the amp.

They're quite small, coming from a stereo amp with just a pair of EL84. There are four wires coming out of each xformer.


Btw, would someone know from which brand are tubes with this marking ? :

An externally hosted image should be here but it was not working when we last tested it.
 
Ex-Moderator
Joined 2003
I'm afraid your output transformers are traditional 3W single-ended transformers and are probably terrible. On the other hand, if you want to experiment and learn, then they are ideal. Try looking at the Mullard 3-3 circuit. The winding with the higher resistance is the primary, and goes between HT and anode. The (much) lower resistance winding is the loudspeaker output (probably 4 Ohm).
 
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