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help for the color-blind guy trying to test a PAS transformer

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I unhooked all leads from the PCB. On the PA-211 transformer, I see a total of 7 leads:
--three tan-colored leads coming out of three nodes at one side of the unit
--two very dark, potentially black leads
--two lighter, possibily red or gray leads
Thinking the darkest (black?) must be the AC in, I connect 120VAC to them then measure AC voltage across the two lighter (heater?) leads. I'm only showing in the neighborhood of .4 VAC when I'm thinking I should be seeing more like 12 VAC
Same thing goes for the "tan" leads. Reading across any pair of them shows less than a volt, which I'm thinking oughta be in the much higher voltage (at least 500?) range.
This transformer came out of a working unit and is assumed good. What am I doing wrong here?
Thanks!

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i think I have it correct now...but - BillyBuck 21:11:09 01/25/07 (0)
But when I connect the PAS to a 70, I get moderate AC buzz before power is applied to the PAS and then very LOUD buzz when power is applied. Buzz is equal in both channels, doesn't follow volume knob, selector switch, etc. so I'm thinking I need to be looking at the power supply. All tubes, including rectifier, are new. Any pointers?
Re: help for the color-blind guy trying to test a PAS transformer - egilbert 21:48:19 01/24/07 (0)
Mine is wired like this:
Looking from the back of the pas dark wires to the right light wires to the left.
The dark side:
The bottom wire (looks Black) to AC (White wire).
The middle wire (looks Black) to AC (Wired to Switch, then to black AC wire).
The top two (Look blue-ish-green) go to the diodes or selenium rectifier.
Light Wires:
Top wire goes to pin 1 on 12X4 tube.
Middle wire goes to pin 6 on 12X4 tube.
Bottom wire goes to the quad cap, I have 4 separate caps and it goes to the negative side of my caps.
You can find the pas manual on Joes home page to compare wiring and voltages.
Hope this helps.
It can be handled easily with an ohmmeter. - Bill Thomas 21:28:20 01/24/07 (0)
Rather than taking a chance by applying 120 V.A.C. to a winding that is designed for only 10 Volts, why not try using your ohmmeter? There are three windings; the Primary, the 10 V.A.C. Secondary, and the High-Voltage Secondary which is center-tapped. First, try to identify the 10 V.A.C. Secondary. It will have the lowest resistance and it will have no continuity with any of the other windings. The Primary will have a significantly higher resistance, but no continuity with any other windings. This will leave three wires which *should* have the highest resistance. Measure between any two of the three wires and note the reading. Then measure between one of these two wires and the remaining wire. If the resistance readings are the same, then the common wire you measured from in both tests is the center-tap. The other two wires are the ends of the High Voltage winding. If the readings differ greatly, the higher resistance reading would indicate the ends of the High Voltage Secondary winding. The remaining wire would be the center tap.
This is a LOT safer than applying 120 Volts to an unknown winding. If you made a mistake and hit the 10 Volt winding with 120 Volts, the Primary winding would be at 1440 Volts. The High Voltage winding would be over 7,300 Volts! (That is, if the 10 Volt winding survived being hit with 120 Volts!)
Try the Ohmmeter method. It's a LOT safer!
Bill

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