Heathkit IM-2264 Digital Multimeter (DMM): History, Restoration, Demonstration, Theory

This video completes my series of documentaries on Heathkit's lineup of digital multimeters (DMMs). I have managed to collect, restore and make documentaries on all of their models.

In this video, I give the same documentary treatment to the IM-2264, which was the top-of-the-line DMM Heathkit made in the years leading up until they exited the kit business.

Because my earlier documentary on the similar IM-2262 covers all of the same circuit theory as this model, with the exception of that required for the added features, I have deliberately avoided repeating that level of detail herein. If you find my brief overview of circuit theory common to both models to be insufficient, feel free to watch the circuit theory section in my IM-2262 video.

Contents of this video:
00:00 Introduction and history
07:44 Internal views & exploration
32:30 Overview and front panel controls
36:58 Making an AC power adapter for this unit
39:56 Restoration
46:50 Re-assembly
51:29 Obtaining suitable test leads
52:28 Beauty Shot
52:39 Demonstration
1:12:13 Schematic diagram & circuit theory (focus is on added features)