Transformer question

[lpd]

Output transformer question here guys. I have an Allan Old Flame Super Reverb clone with Thordason Meissner opt. Only one secondary is connected which is green. The other two secondary colors are green with a yellow stripe and white. Anyone here know the impedance of these taps?

Thanks

[maxkracht]

Without desoldering anything and doing proper measurements, you can probably do a quick and dirty resistance test If you already know what the impedance of the current tap is. You can assume the options will be 2,4,8,16. The numbers will be pretty small (.5 - 2 ohms ish), but you should be able to get a relative number. More resistance = larger tap. If your meter doesn't go that low, you can add a small resistor in series to get it in range, these are relative numbers after all.

[alkuz1961]

You can get quite reliable data for the output transformer if you apply a AC voltage to the primary winding, measure the voltage on the secondary windings, and determine the transformation coefficient.

[lpd]

Thanks guys!

[dorrisant]

You can get quite reliable data for the output transformer if you apply a AC voltage to the primary winding, measure the voltage on the secondary windings, and determine the transformation coefficient.

What he said.

[Stevem]

If the amp still works and the OT is still in the amp just run a text tone thru it and read the ac output voltages and you will find out what you want to know.

Since you're talking about a SR clone amp I will assume you will find that the OT has 2,4 and a 8 ohm taps.

The OT will sounds its best and live a longer life it it’s being driven hard if you run it on its highest impedance tap!

[alkuz1961]

You can get quite reliable data for the output transformer if you apply a AC voltage to the primary winding, measure the voltage on the secondary windings, and determine the transformation coefficient.

What he said.

Was that a question? Okay, I'll explain. The mains voltage in the wall outlet is 230 (or 115) volts. The output transformer is designed for a much higher voltage of the anode circuits, and can easily accept the mains voltage. We connect the transformer to the outlet, measure the voltage at the input and then take turns making measurements on the output windings. In this way, we can determine the transformation coefficient. All other data can be obtained by calculations.
Btw, In the same way, you can presence of problems in the windings of the transformer. If there are any problems it will heat up quickly enough.

[dorrisant]

No question... you stated fact and beat me to it. Sorry, American colloquialism.