Anyone familiar with Heathkit®?
From 1947 to 1992, the U.S. based Heath Company produced electronic kits for everything you can imagine: radios, TVs, computers, robots, ham gear, and electronic test equipment. Yes, you guessed it – they also produced kits for oscilloscopes! [Flash news – Check out Chuck Penson’s latest book, exploring Heathkit’s history of Test Equipment production. It’s a great read!]
My Grandpa purchased one such scope, the Heathkit OR-1, around 1960. He wanted to kick off a new career in electronics repair, and the ‘build-your-own-equipment’ approach to training was in full bloom at the time. Also, since this was before the era of cheap overseas manufacturing, he could buy a Heathkit far cheaper than an assembled scope.
Heathkit OR-1 manual – a work of art
Unfortunately, Grandpa’s electronics career never really took off. But decades later, he introduced me to his gorgeous oscilloscope, and boy – did that kick MY career off! Much later, the OR-1 came to live with me. (You can read a bit more about my affinity for this scope in my History page.)
The problem is, I have too many oscilloscopes. But I don’t have enough Oscilloclocks. What more fitting way to keep Grandpa’s legacy alive, than to retrofit his Heathkit?
Special features
Circle Graphics (see my earlier post) makes for smooth, graceful characters constructed entirely from lissajous figures! Never before has an oscilloscope looked so utterly delightful.
The horizontal sweep frequency fine adjustment knob, conveniently located smack in the middle of the front panel, functions as the single control for the Oscilloclock. (A video showing what this control does is up on my YouTube channel.)
Eventually I might make an acrylic case, to show off not only the CRT but also Grandpa’s soldering prowess. In preparation for that, I’ve made sure that all the tubes (valves) still light up when you turn the original power switch on. What a beautiful scene!!
The 5ADP2 CRT in the OR-1 is decidedly unattractive compared to other tubes I used in the Model 1 and the Prototype. It is also technically inferior, not having post-deflection acceleration. However, it has one redeeming feature – a P2 phosphor! This phosphor gives just a hint of blue, and it has a simply divine after-trace of just the right length to create soft, flowing figures while still maintaining reasonable sharpness and clarity. (Visit my earlier post for more info on the phosphorescence phenomenon!)
The Oscilloclock boards are mounted on attractive acrylic back-planes and are easily accessible from the side and top. Image size and position adjustments can be made with the case on. The case can be easily removed to reprogram the clock:
The OR-1 happened to have a trimmer control at the back, so I tucked this control inside the unit, leaving a nice big hole – perfect to mount the socket for the Garmin GPS unit. This baby never loses track of time!
Like what you see?
If you have a cherished oscilloscope that you wish to preserve in entirety, but also want to put to practical use in your workshop, office, coffee shop, or museum, converting it to an Oscilloclock is a nice idea!
However, the conversion process depends heavily on the oscilloscope you have, and your preferred approach. There is no single ‘cookie-cutter’ step list, although the Oscilloclock boards are designed to be relatively flexible.
To see some construction highlights from this conversion, be sure to visit Making the Heathkit Oscilloclock!
Lastly, a note regarding Heath Company: As far as I can tell from their web site, they are in business again, and are even planning to re-start kit production! They of course own the Heathkit logo and trademarks referred to in this article. It is my hope that rendering their logo on the Oscilloclock will not offend them.