[dagskarlsen]

If you have got 70 volts an the line with receiver in on hook posision the magneto is right. The internal ringer should ring when you crank the magnot according to that diagram. White and red to one terminal, green to another on the magneto, the third terminal is not in use. When you go off hook, the crankig should be harder, and you should hear it in the receiver. The old transmitters (microphones) was not depending on polarity, and worked well on 1.5-4.5 Volts depending on the make. For electronic replasements , the voltage may be higher, and poarity may matter.

I,m not sure of the model, but this one has an Anti-sidetone circuit, and those were late at North American magneto telephones.