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Output transformer Question

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The amp is a Leak(British company)Amplifier from about 1960.See Schematic.I am restoring this but when I measured the output resistance this is the readings I got.First don't the reading seem low for a output transformer and second,why is the center tap not equally resistance from the ends. I thought at first that the output transformers were bad but they are both identical.Why is't the center tap in the middle of the transformer?
 
On a cheaper (less interleaved) transformer, it can simply be because the turns get longer as you get further from the core. Each side has the same number of turns, but the ones further from the bobbin are longer and thus have higher resistance.

I do not see a schematic.
 
An externally hosted image should be here but it was not working when we last tested it.
I,m trying to upload from my computer
 

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Bandersnatch said:

2k CT to 600 CT is a 1.83 step-down. Or for headphones...:) The frequency response is a bit light( 50 to 10k cps. )


My eyes see it as 9000 ohms CT. This is a mil. spec. transformer and 50-10,000 ~ is what the Government needed and wanted to see written on the part. It's been my experience with transformers like this that the bandwidth could be considerably more. Especially at less then rated power.

Victor
 
Tweeker said:
On a cheaper (less interleaved) transformer, it can simply be because the turns get longer as you get further from the core. Each side has the same number of turns, but the ones further from the bobbin are longer and thus have higher resistance.

I do not see a schematic.

It can be done to get both sides of the CT the same length( with the same turns count, and thus same resistance). It is not a function of interleaving, but of interleaving for that end. I suspect that focusing on better couplilng instead of equal resistance is a better idea. Compared to the Dynaco/Acrosound style it is easy to get closer to equal length/equal resistance halves with more complex interleave.
cheers,
Douglas
 
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