Dad’s Shop: Part 2, the Heathkits

We of course did a lot of woodworking and other non-electronic work in the shop, but when it comes to electronics, the projects that stick out most in my mind are the Heathkits. My dad, like many others, took advantage of technical training programs available through the GI Bill to people who had served in the military. He had been educated in tube electronics at U.S. Army Signal school in Fort Monmouth, New Jersey, where (among other things) he assembled and disassembled a typical superheterodyne tube radio as part of the training. As a result of this, he had excellent soldering and debugging skills, and he later applied for a correspondence course to learn about servicing color TVs. The great thing about these courses was that, as part of your training, they would send you the pieces of a TV kit to assemble bit by bit, and at the end of the course, you would have a color TV you could use in your house—for free!

There have been many companies over the years that sold electronic kits. Before manufacturing became largely automated, driving down assembly costs, putting together your own electronics by soldering parts and connecting pieces could save you money over buying something that had already been fully assembled. Kits like Eico, Paco, and Allied Radio Knight Kit were popular and frequently appeared in many hobbyist and electronics catalogs. By the time I was old enough to build my own kits, this business had mostly dried up (to my disappointment), but we still had the fruits of several kit-building exercises in our house. These were all Heathkits—arguably the king of electronic kit companies. Their catalogs were filled with pages and pages of TVs, radios, stereo systems, speakers, ham radio gear, and test equipment. As a kid I would pore over these pages dreaming about all the cool stuff I could build, though the number of kits listed in the catalogs I had was a fraction of what it had been in Heathkit’s heyday. As my dad likes to say, Heathkits were not cheap, but they were high quality and often featured advanced features that would be even more expensive in a commercially-built product. Plus, they came with detailed and easy to follow build instructions that not only took you through (hopefully) successful construction, but also guided you through troubleshooting any issues that occurred, and even gave you some electronics theory in the process.

We had three Heathkits in our house, all painstakingly assembled by my dad from thousands of discrete components: two color TVs (GR-180 and GR-2000) and a stereo (the famous AR-15). For the smaller color TV and the stereo, my dad built beautiful walnut enclosures. The cabinet for the stereo also held a turntable and included room to store LP records. I still have this cabinet, along with the turntable and most of my parents’ records, but the AR-15 in the cabinet is a different one that my uncle put together (my dad kept his original stereo to use in a different enclosure). I remember that both TVs had a great picture, in part because the Heathkit manuals also told you how to perform the periodic service adjustments that all TVs at the time required for the best possible picture (Heathkit TVs actually came with several thick books of construction, alignment, and electronic theory information). As I got older, I became fascinated with these procedures and would align the TV once or twice a year, far more than it probably needed, but I didn’t care—it was fun to see the results of my work and know that every time I watched the TV, the clear, sharp picture was due to my adjustments.

Christmas 1974 at our house, showing the Heathkit GR-180 color TV with custom-built walnut cabinet!

As the TVs aged, some of the components began to fail. Usually the fix was quite simple, involving the replacement of one part at a cost of around a dollar or less, and this often required a visit to our local Radio Shack or to Superior Electronics, a parts store in Madison that had a wider selection of discrete components. Superior no longer exists, but I’m very lucky to have an amazing parts store, Anchor Electronics, close to where I live now. Anchor is even better than Radio Shack ever was because you can inexpensively buy many different kinds of components in low quantities.

The kits my dad built were quite reliable. On the rare occasions when one of the TVs (or possibly the stereo) went on the fritz, my dad would bring it down into the shop, open the case, and sit me down for a lesson. I recall him always asking me, “What do we check first?” And the answer was always, “The simplest thing.” Make sure the fuse or circuit breaker isn’t blown, and make sure the plug is in good shape. Next was usually a visual inspection—components that go bad will often get very hot before a fuse blows or someone notices a burning smell and turns off the equipment. Often it’s easy to spot a blown component and associated burn marks. From there, we pulled down and dusted off the Heathkit manual(s) and started following the troubleshooting guide, which was organized by symptom and helped you isolate failures to a particular circuit board and, often, to a specific component. Sometimes when components start to fail, they become sensitive to heat, and I remember using a can of freeze spray to squirt suspected components while listening to the radio or watching the picture on the TV. If a hot component was the issue, the effect of the spray would be dramatic (often the problem disappeared completely), which never failed to fascinate me—”Spray it again, Dad!”

One of my crowning glories in electronics debug came when I was a senior in high school. By this point, friends and family knew of my interest in electronics and I was regularly getting donations of non-working equipment with a friendly “If you can fix it, you can have it!” I had dreams of setting up a complete entertainment center in my room, and these dreams came one step closer to reality when my dad brought home a 25” Heathkit GR-370 color TV. He had gotten the TV from a coworker, who had almost fully assembled it but then gotten stuck at one of the initial power-on stages when he couldn’t get a picture (before modern digital TVs, TV screens displayed snow when there was no channel tuned in, this one was just a black screen). I had the TV set up in the shop and regularly headed downstairs after dinner and homework to do some detective work, often with my dad assisting me and making suggestions.

After some false leads and dead ends, I went over the troubleshooting section of the manual from the start again and determined based on what I already knew that the problem had to be on one particular circuit board (there were 9 modular circuit boards, each performing a different function, that plugged into the back of the TV chassis). I took out this board and went back to my old standard, the visual inspection. One of the parts on the board was a transformer, which could be installed in two different orientations but would only work in one. All of the circuit boards in the TV were silkscreened to indicate where the components went, and if a component could only be installed in one particular orientation, there was usually an indication on the silkscreening. This transformer was no different—in big letters at one corner of the silkscreened transformer outline, it said “DOT,” indicating that there was a paint dot on the transformer that should align with the DOT on the circuit board drawing. Sure enough, there was a green dot on the transformer in the proper alignment, but something about the dot looked odd. It was very faint, and the plastic under the dot was rough, almost as if this was where the plastic injection had occurred in the mold. On a hunch I looked on the other corner of the transformer and there was a red dot that looked more substantial, like it had been painted on. Curious, I went back to the build instructions for the circuit board, and clear as day in the step-by-step assembly checklist, it said “Install the transformer with the red dot aligned to the silkscreen diagram.” Eureka! The color of the right dot was probably an easy detail to overlook after hours of soldering part after part, one at a time. I desoldered and removed the transformer, flipped it around so the red dot (not the green one!) was aligned to the silkscreen, and reinstalled it. It’s hard to describe the euphoria of solving a tough electronics problem, but when I turned on the TV and heard the whoosh of high voltage and saw the screen light up with snow, I pumped my fists in the air and immediately ran upstairs to tell my dad—all those years of helping him debug and fix Heathkits in the shop had paid off!

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