I was asked by a friend what this could be?
He is a hobbyist train fanatic - this is a part on a 1950's engine (model train) and has voltage wires coming in and then leading out to other parts.
My guess was a splitter of sorts but if anyone here has any pearls to offer, he would be very grateful for any guidance.
thx..dB
He is a hobbyist train fanatic - this is a part on a 1950's engine (model train) and has voltage wires coming in and then leading out to other parts.
My guess was a splitter of sorts but if anyone here has any pearls to offer, he would be very grateful for any guidance.
thx..dB
Going to guess tapped wirewound resistor. Other guess would be selenium bridge rectifier.
If it measures like a resistor you are good. If it looks like a rectifier, do not power it up. Burning selenium rectifier vapors have some health hazzards.
If it measures like a resistor you are good. If it looks like a rectifier, do not power it up. Burning selenium rectifier vapors have some health hazzards.
If that's in a model train, it is almost certainly a selenium bridge rectifier. Lionel and other toy trains used AC on the track, but had DC motors, so they needed a bridge rectifier to convert the AC to DC. You may also find a "reversing unit" inside, which is a solenoid operated, rotating DPDT switch that would reverse the polarity to the DC motor when the AC power was briefly interrupted. Crude, but clever.
These rectifiers don't last forever, and as mentioned above, can emit harmful vapors when they fail. I don't know what collectors are doing to replace these, but due to the popularity of the hobby, I bet someone has come up with a drop-in replacement. That terrible cloth-covered wire should be replaced, too. I get scared just looking at it! But of course, if this will just be a static model, then do nothing but sit back and enjoy.
These rectifiers don't last forever, and as mentioned above, can emit harmful vapors when they fail. I don't know what collectors are doing to replace these, but due to the popularity of the hobby, I bet someone has come up with a drop-in replacement. That terrible cloth-covered wire should be replaced, too. I get scared just looking at it! But of course, if this will just be a static model, then do nothing but sit back and enjoy.
It's common practice to replace the selenium rectifiers that were traditionally used to power the bias supply in old tube amplifiers with a silicon bridge, with perhaps a series resistor to knock down the bias voltage a trifle to a level similar to that generated by the original selenium part. The resistor may also be a good idea when replacing the selenium rectifier in the model train with a silicon alternative, unless you like your trains to run a little faster, as the silicon bridge will have a lower voltage drop than the corresponding selenium part - its dynamic impedance is also likely higher than a .silicon rectifier (translation - a selenium bridge will act more resistive than a corresponding silicon diode bridge).
Looks more like a ww resistor to me, selenium rectifier would likely have equally spaced sections