Checking out some recent acquisitions - #11 - Almost a Heathkit Blue Box, the IM-1210 Meter.
Friday, August 7, 2026 at 07:04:23
Here’s another one of Heathkit’s plastic boxes from the 1970s. This one is the older brother to the Heathkit IM-1212 NIXIE meter, the one that was provided as part of Heathkit’s electronic labs for you to build and maybe understand how it works. Maybe…
Here’s the IM-1212 if you’d like to see what that one looks like, and you’ll certainly notice some similarities in the circuitry: https://wereboar.com … aking-it-work-again/
This one is updated to use LEDs, as by the time this was made NIXIE tubes were obsolete and getting harder to find. It has the same issues as the older one, however, that of being as stable as the drug dealer down on the corner of 6th and Walnut…
So let’s check it out. Here’s the front, it’s a good looking unit and has the same ranges as the older one.
The top, bottom, and back…there’s not much to say about those.
The device has a polarized grounded cord, which someone cut off the ground prong. Don’t do that!
Here’s the inside. Same parts with a different layout, including the calibration voltage on a tag. I’ll pull a manual to see where everything is and see if it will calibrate (at some point, not today!)
So, does it work? Yes.
That’s supposed to be 14.6VDC, so it’s off. Surprise, right?
This one will probably show up later as a one-off calibration, stay tuned!
Next part of this series: Coming sometime?
Previous part of this series: https://wereboar.com … -the-it-5283-tracer/
References
Assembly and theory manual: https://wereboar.com … ssy%20manual.pdf.zip