Heathkit VTVM IM-18

Time to pull the old VTVM off the shelf and see if it’s worth refurbishing. Bad news…..!

[@HighCompressionII]

Do yourself a favour, Replace the 4 resistors between the batt cup and the 12au7 valve socket, (150k x 2, 220k, 27k) use 1w metal film. Also, replace 12au7 with 600-900v MOSFETS, use 22k gate stopper, source to K, gate to G, and drain to A Build up on B9A valve plug base, plug in, and there ya go. It'll be much more stable, and instant on for DC ranges.

[@HighCompressionII]

Ah well, I just watched the end... Shame the meter coil is dead. Maybe you could repair that wire break, give it a try--nothing to lose, it's buggered anyway!

[@timtimeprojects3576]

I like the way you think.

[@marcuscheko3264]

well dang !!!! was hoping id get to watch a repair on something this morning ...maybe next time ....ive got to look at a heathkit 1480 i think its a coax remote switch

[@timtimeprojects3576]

Sorry, there hasn’t been any good deals around for old stuff. I’ll keep looking for something to work on. Good luck with your switch.

[@mgillard96]

Hey Tim and others, would replacing the power supply be the fix? What exactly is broken here? Mine has the same problem of flashing on plugging it in after a power outage. Is it something in the power circuitry or the supply itself?

[@fredcooper2063]

....Aw, real shame!! I have just about refurbished the self same meter, & its now working just fine!!! Mine just now has only a cracked meter glass, don't suppose you would be interested in selling your meter glass?? { They ain't too easy to find, these days!!?? } Cheers, Fred G4ZWI

[@timtimeprojects3576]

Unfortunately mine too has a crack in the upper right corner. Even so it would probably cost a lot to ship across the pond.