I have an unknown transformer question. As you can see, the secondary is made up of two yellow, two orange, two red and one black. There is continuity between orange, red and black, not yellow. Voltage readings are:
Yellow - 15v
Orange - 56v
Red - 96v
Assuming the black wire is a center tap, I get ~26v on each orange and ~46v on each red. So, what is the black wire?
Tom
Yellow - 15v
Orange - 56v
Red - 96v
Assuming the black wire is a center tap, I get ~26v on each orange and ~46v on each red. So, what is the black wire?
Tom
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If you are using a meter with high input resistance you are probably measuring leakage between the windings. I suggest you put a 10K Ohm resistor across the meter probes to shunt away the miniscule leakage currents, and then measure again from black to each of the other secondary wires. If the reading is zero the black is probably an electrostatic shield that should be grounded.Assuming the black wire is a center tap, I get ~26v on each orange and ~46v on each red. So, what is the black wire?
OK, it seems one of the windings is red - orange - black - orange - red. ie. 46 Volts aside of the CT, with taps at 26 Volts. From either red, do you read ~20 Volts to one orange and ~72 Volts to the other orange?Glenn, I tried the 10k resistor and it's still the same thing. The black seems to be common to both the red and orange wires.
Good. Yes, black is CT. Here is an example of generating two different positive DC supplies. Overlay the same design with reversed diodes to add negative supplies, relative to the CT.Yes, that's exactly what I get when I measure from any red to the orange wires. I think it may have come out of one of those all-in-one integrated amp things. So, no matter which color I end up using, (red or orange), I should treat the black as a center tap?
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I think it may have come out of one of those all-in-one integrated amp things.
You're on the right track here, 1980s-early 90s with a cd player on the bottom and record player ontop if I remember correctly.
Chip amp.
These transformers I usually throw away because their windings are really just 'odd', but good luck finding a nice chip amp and cd transport project to put it to good use on.
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1980s-early 90s with a cd player on the bottom and record player ontop
Yeah. I found it at the landfill in the electronics bin. I was just looking for parts. It had a nice, big heatsink in it and Toshiba 2SC3281's and 2SA1302's.
Tom
Ok. Here are the DC resistance values:
Black to Red 1 = .4
Black to Red 2 = .4
Black to Orange 1 = .3
Black to Orange 2 = .3
I hope that's what you meant by DC resistance readings.
Tom
you have one nice traffo there....
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