Wednesday, July 09, 2014

Heathkit VC-2 Voltage Calibrator

I picked this up at OSU last winter, finally got around to checking it out a bit. I’m not really sure what this is specifically useful for. It outputs a square wave of a settable voltage. I’d love a scan of the manual as I haven’t found one on the internet.DSCF2694 DSCF2695 Benny the Beaver.DSCF2697 The peak volts scale is obscured by a replacement graduated dial.DSCF2699 DSCF2700 Set up on the bench.DSCF2704 DSCF2705 4.26V when set to 4V…DSCF2707 DSCF2708 9.36V when set to 8. I’m guessing that the dial is not graduated correctly. Why is it there then? Who knows.DSCF2710 DSCF2713 DSCF2714 An internal potentiometer.DSCF2716 DSCF2719 The internals are typically simple and beautiful for the age.DSCF2724 Removed the aftermarket dial face. Have to give it to my friend SpudDSCF2725 DSCF2726 With the dial removed it seems more accurate?DSCF2728 DSCF2729 Almost spot on…DSCF2731DSCF2730  Not so much at the .1V multipler,DSCF2732 DSCF2733 Nor at the 10x multipler at 1V(x10=10V)DSCF2735 DSCF2736 At 2Vx10 I get 22.6V, so there’s a pretty consistent extra 2.6~ volts.DSCF2737 DSCF2739 But at 5Vx10, I do get almost 50 volts.
I don’t think this was meant to be a precision reference, although I may be wrong. I could play with the internal potentiometer I suppose. Anyway, a neat thing.

1 comment:

Renal Circle said...

I might try and I will look for a manual for you...

Seems it was intended to output a highly accurate and stable voltage in the form of a square wave to calibrate other diagnostic tools like a scope. Also assume that you needed to leave it on a bit to let it warm up as it used tubes.