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Testin a speaker and output transformer Trutone A2-G
#1

Hello guy's,
Have a Trutone A2-G teledial floor model radio that I am having issues with.
Suspecting maybe speaker or output transformer.
This speaker has a 5 pin connector, so I am not sure how to check it with my ohm meter. Used to 4 oin connectors.
Problem I am having is volume issues. Plays fine at lower volumes and goes south after mid range on the volume control.
Has been recapped and the transformer was replaced by previous owner.
Cadohm resistor is replaced as well as a handfull of resistors.
How do I check the speaker and output transformer on this 5 pin connector.
Tubes have all been verified as OK on my tube tester(Hikcock).
Checked voltage on rectifier tube and it is checking about 285v.
Checked on speaker socket and its about the same.
Idea's without getting to technical?
murf
Hey Murf, this shouldn't be too difficult if it happens all the time. I'm assuming this is the 1938 Wells Gardner A2 with the Truetone label. You haven't said if you have any test equipment but if you can inject an audio signal either with an audio signal generator or your finger touching a small screwdriver at each grid point of the audio path you should be able to locate the culprit. I'm pretty sure if the output transformer has problems it wouldn't give the symptoms you describe.

So, tune in a station, if you place the vol control at the point where sound quits then touch the 6J7 grid cap at the top of the tube and you get an output noise from the speaker then the problem is the volume control. (Maybe it should be cleaned). I'd put my money (2 cents) it's the control.

You can also go the other direction. Start with the 6F6 output tube grids but they are harder to get to.




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