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

Power Transformer Question

Got this PT below, as you can see it has 2 235v @ 60ma winding. Can I connect terminals 3 and 4 to create a center tap for a 235-0-235v @ 160ma?

Also the input is 115V @ 50Hz how will this be effected by a 60 Hz input.

Wanting to use it for a preamp.

BL
 

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When connecting terminals 4 and 5 to form a center tap, if the voltage then between terminals 3 and 6 is small and not ~470VAC, remove the connection and jumper instead terminals 4 and 6. Now check for 470VAC between terminals 3 and 5.

It will perform better at 60 Hz than at 50Hz.
 
Got this PT below, as you can see it has 2 235v @ 60ma winding. Can I connect terminals 3 and 4 to create a center tap for a 235-0-235v @ 160ma?

Also the input is 115V @ 50Hz how will this be effected by a 60 Hz input.

Wanting to use it for a preamp.

BL
Connecting T3 and T4 together will short out that winding and destroy the transformer. Connect terminals T4 & T5 together to get a CT. If you get no voltage across the pair of windings, then reverse the polarity of just one of the two windings; either one will do.
 
Blind Lemon,

Before making any connections on the secondaries, I suggest to connect
the primary to 115VAC and measure the AC voltages on all secondaries,
especially compare the voltages on 3-4 and 5-6 windings.
I find it suspicious that 3-4 depicted with 4 "turns" and 5-6 depicted
with 3 "turns"...
Also, make sure that your transf is not buzzing with only primary engaged.

<Would it still only handle 60ma with using it as 235-0-235 because its
in series not parallel?> -Yes.