- 2025
- Apr
- 22
The Heatkit AF-1 Analog Frequency Meter, Part 11 - Wrapup and final thoughts.
This was an interesting device - not in the circuitry, as there was nothing in here that’s really unusual, but in the device itself. This was sort of a “because we can” device that was rapidly made obsolete by changing technology, and something that would have been difficult to calibrate without some sort of advanced tech. Regardless, it’s a rather unique piece that I’m happy to have in my collection.
What is there really to say about this device? Not much. It was a straightforward rebuild, and other than finding an actual schematic for the device, presented no issues other than the mystery of the potentiometers. That was apparently noticed by the original builder as well, seeing as how they had been changed for parts that were far in excess of the specified values.
A note on the schematics: Heathkit published a book of devices with schematics, and this is where the one you’ll find online came from. It’s a pre-print, and is wrong. If you have one of these, you’re well served by going to ManualMan and getting the manual for the device. But if you can’t get that, here’s what I found during the rebuild:
That’s about it. The device itself has a display spot on the shelves, but it’s not necessarily the most useful thing - especially considering that I used a modern counter to align it! But still, it’s a piece that reminds us that technology changes, often times quite rapidly.
The entire series:
The Heatkit AF-1 Analog Frequency Meter, Part 1. https://wereboar.com … quency-meter-part-1/
The Heatkit AF-1 Analog Frequency Meter, Part 2 - Testing. https://wereboar.com … eter-part-2-testing/
The Heatkit AF-1 Analog Frequency Meter, Part 3 - Schematic Corrections. https://wereboar.com … hematic-corrections/
The Heatkit AF-1 Analog Frequency Meter, Part 4 - Parts. https://wereboar.com … -meter-part-4-parts/
The Heatkit AF-1 Analog Frequency Meter, Intermission. https://wereboar.com … -meter-intermission/
The Heatkit AF-1 Analog Frequency Meter, Part 5 - A different approach. https://wereboar.com … -different-approach/
The Heatkit AF-1 Analog Frequency Meter, Part 6 - The power supply. https://wereboar.com … -6-the-power-supply/
The Heatkit AF-1 Analog Frequency Meter, Part 6b - Testing the power supply. https://wereboar.com … ng-the-power-supply/
The Heatkit AF-1 Analog Frequency Meter, Part 7 - Rebuilding the filter. https://wereboar.com … building-the-filter/
The Heatkit AF-1 Analog Frequency Meter, Part 8 - Rebuilding the rest of it. https://wereboar.com … ding-the-rest-of-it/
The Heatkit AF-1 Analog Frequency Meter, Part 9 - Testing the rebuild. https://wereboar.com … testing-the-rebuild/
The Heatkit AF-1 Analog Frequency Meter, Part 10 - Final assembly and test. https://wereboar.com … l-assembly-and-test/
The Heatkit AF-1 Analog Frequency Meter, Part 11 - Wrapup and final thoughts. You’re reading it now!
Next up is a PACO G-30 RF signal generator, one of many cheap devices of it’s kind from the 50s. Stay tuned!
Previous part of this series: https://wereboar.com … l-assembly-and-test/