Uploaded February 2025 | Updated September 2026, 1 week ago

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In this video, I document the Heathkit model ID-4850, and by extension the somewhat less capable model IC-4802, which were Heathkit's only digital oscilloscope offerings to be designed and manufactured in-house. I had built and owned one of these ID-4850's in the year 1987, and used it extensively for a few years for the purpose of capturing waveforms on equipment for which I was tasked with writing technical manuals. I later sold mine original ID-4850, but recently purchased the one shown in this video from an eBay seller.

In the video, I cover the instrument's history, I give an internal and external overview, I demonstrate it in operation in both modes of operation (connected to an analog oscilloscope and connected to a computer), I give a look through the two manuals, and finally I give an extensive presentation on the circuit theory of operation while perusing the schematic diagram.

Timeline Table of Contents:
00:00 History
05:40 Overview of Front Panel
09:49 Initial Test & Demonstration Connected to an External 'Scope
12:22 Internal View
25:01 Demonstration, Connected to a Computer
34:53 Cleanup for Display
35:41 Power-Up Sequence
36:15 Beauty Shot
36:35 Assembly Manual (overview)
49:12 Operation Manual (overview)
1:02:54 Schematic Diagram & Theory of Operation