What the H*%L is this?

[dedrekon]

I figured somebody on this forum could tell what this thing is, I've owned it for years.

Vincent

[barnstmr]

Re: What the H*%L is this?

It is a variable resistor. Something very similar is used to "parallel" alternators on twin Cessna's.

[flyguy]

Re: What the H*%L is this?

Man that thing is old. Believe the name is rheostat. Was used in school laboratories and test labs. It is a wire-wound resistor that is set up so you can use it as a voltage divider. I suspect the support cylinder is made of ceramic so you can heat it up and not burn it up. Suspect the wire is nichrome--the ones I have seen were. Will light up like a electric stove coil if you get carried away (that is why the wire is black).
Hook 12 volts across the coil, set the slider to the middle and you get 6 volts, and a warm room, Chuckle.

Could use it to compare 1 thru 9 volt analog meters ( with a pointer, remember) with a more precise meter when you only have a 10 volt source.
Darryl

[DPKII]

Re: What the H*%L is this?

Yep, a rheostat (variable resistor). Basically a wire wound resistor with a moveable tap-slider. By the marking on the knob my guess would be zero to fifty ohms. Test it with a Ohm meter across the end terminals or hook it to a battery in series with a light bulb. Moving the slider will vary the current making the bulb brighten or dim. Be carefull not to set it for a low resistance with a high capacity battery or as stated - High current - the wire will glow possibly ruining the resistor.
Thanks,

David

[N74DV]

Re: What the H*%L is this?

that's one old wirewound resistor! any interest in selling it? I collect things like this

[perryv1]

Re: What the H*%L is this?

My guess is that it isn't a very high current resistor,the size of the winding tells me it wont last long at anyting above 10 amps or so.Still, its really cool.
PV

[Bird]

Re: What the H*%L is this?

I had something like that on a crystal radio set and seeing that it was made by zenith I would be inclinded to say it was used for a radio