Pictures and info supplied by napervillesoundtech:
I was working in an old wiring closet in a school, and came across this. They gave it to me, along with another weird board (another set of pics). I am not sure what it is. The shaft tightens with a little bolt and can be raised and lowered. It also looks like it has some sort of capacitors on it. I have not plugged it in; however, I did drag it back to my shop and test it with an ohmmeter. There is a complete circuit through everything. I just thought you might get a kick out of seeing it.
Thanks Ben. [This message has been edited by Trumpy (edited 03-02-2006).]
Great to see this old stuff, my guess is that it is probably 1920's. I have to agree with the other comments that it is probably from a science class and used for showing students what a variable inductor does and a capacitor in series with an electrical lamp circuit. What are the voltages from the lamps ? 110 Volts or different ? It looks like there are 3 capacitors on top of each other in parallel. they may have been used as singles too to show the different brightnesses of the lamp with different cap. values.
The product of rotation, excitation and flux produces electricty.
#152910 - 03/04/0602:12 PMRe: Frankenstein's been robbed!!
If I were a physics tteacher, I'd want to use this in the lab. But first I'd enclose it in a clear plastic box to avoid the shock hazard. The variable inductor's control handle would poke thru a hole in the top of the box so the students could safely play with it. And that cap probably needs to be replaced.
#152912 - 03/04/0610:10 PMRe: Frankenstein's been robbed!!
The caps are surrounded by a thin metal shield, which has a thick coating of black paint on it. I think if I pull that shield off, I may be able to see the values on the caps. I too am a little curious as to how well this works.