Vintage Ballantine Labs 643 Decibels AC Volts 1-10 0-20 VOLT Meter UNIT #300

on top marked SPECIAL PRODUCTS ENGINEERING.

LIGHTS UP NO FURTHER TESTING DONE.   HEAVY.

GOOD CORD, FROM HAM RADIO ESTATE .  APPEARS COMPLETE, NO PROBES.

THE STRAP is not broken, but has cracks from age.  I would not pickup by the strap.  dry rotted.

see tag:   Electronic Voltmeter model 300   - Ballantine Laboratories.

might be military era , not sure.   see all pictures.  big unit , about 12 inches tall.

I played with knobs, did not react, but might need a signal input.   no probes. no directions.

as-is, as found, thank you