Amateur radio has a long history of building. Whether from the earliest days of the hobby where nearly every component had to be constructed or modified slightly to convert a landline Morse component into wireless service all the way to the present with the plethora of kits from various manufacturers, radio amateurs have been building their own equipment. Sometimes building is a means to save a bit of money up front; other times building is required because the new idea doesn’t exist in hardware (or even software) yet. Many times building is done for the pure pleasure of the activity. I probably fall into the last category.
My journey into the home construction phase of amateur radio began with the Heathkit HD-1416 code oscillator in early 1982. This led to the Heathkit SW-717 shortwave receiver not long after. Later I added a digital clock to the lineup capable of 24 hour display, the HW-8 QRP transceiver, and HW-5400 HF transceiver with associated power supply by early 1984. Later years saw construction of various homebrew items and partial kits such as the Idiom Press Super COMS 3 Morse keyer, several repeater controllers, a 30m QRP transceiver and most recently the partial kits of an Elecraft K3 HF/6m transceiver and its companion P3 panadapter. Building of some form has been a part of my amateur radio experience from well before I was first licensed.
Some months ago I was rummaging through my old bedroom at my folks place and found the first kit I ever built, the Heathkit HD-1416 code practice oscillator. A code oscillator doesn’t do much except produce an annoying tone in response to input from a Morse Code hand key. That was the point, to allow for practicing sending Morse Code without using a transmitter of any sort. In a classroom setting an instructor can use one to send practice text to the students and at home the student can practice Morse Code by hearing his own sending and trying to make sense of it!
After a bit of cleanup and replacing the dead battery, which, thankfully, did not leak after all these years, the oscillator began squeaking with the first key closure! The oscillator itself is housed in a rigid plastic case and has provisions for using headphones (presumably to preserve family peace) and a volume control.
The key is demonstrably cheap! The main lever is made of soft stamped steel and is prone to flexing should the spring tension be set too tightly. The pivots are not adjustable and only have the most crude plain bearings. This is not a key one should use for a QSO lasting more than 10 to 15 minutes. For its intended purpose it is adequate.
My scribbling of my Novice callsign on the key support was none too professional! Also, the block is far too thick for comfortable use. It was what I found laying around at the farm at the time. I would learn over time that an inch thick board was a bit too high.
The circuitry is not complicated which is essential for a first time kit builder. I don’t recall doing much soldering practice before I built this kit. Evidently I must have done well enough as nearly 31 years later it still works.
The blue potentiometer on the near side sets the tone frequency from quite low to squeaky high. The battery and speaker holder bracket is nicely designed. Originally, the battery rested on a couple of strips of foam the remnants of which can be seen at the end of the battery on the circuit board. Otherwise, the speaker and board have survived well after all these years.
Finally, it really was time to change the battery. I have no idea how old it is, possibly from the mid ’80s at the latest would be my guess. I was concerned that it might have leaked. Fortunately, it did not and any damage was averted.
For me, this humble kit gave me the confidence to continue building kits of various levels of complexity and provided hours of enjoyment in the years to come. It also led to doing a bit of breadboard experimentation with LEDs and ICs in following years. I was also well prepared for electronics lab work in tech school several years later where building a couple of kits and then troubleshooting them was required.
The Heathkit manuals are legendary for their complete assembly guide and being nearly free of errors. Some modern kits do have manuals that rival the Heathkit manuals of yore while some others are little more than construction notes and a parts list. With a little practice any level of kit can be built and the reward is firing it up for the first time, and also 31 years later!