Down the Rabbit Hole
Building a solid state DC converter to power a 1950’s era mobile tube transmitter. The build uses an NOS Triad TY-83 toroidal transformer and high-power germanium transistors – the best available power conversion tech in the late 1960’s and early 1970’s.
Using several 20-foot 2 by 4’s that were left behind by the construction crew, and adding four 8-foot 4 by 4’s for mounting posts, there was enough lumber to build two 36-foot tilt-up masts. Spaced 150-feet apart, they supported a multi-band Zepp antenna center-fed with open-wire line.
I was having a lot of fun with the restored Ten Tec Omni (series C), but like all of the older Ten Tec radios, the Permeability Tuned Oscillator (PTO), aka VFO, left a little to be desired. Back in the day, when I bought my first Ten Tec, these PTOs were considered very good — but time marches on and we’ve gotten used to smoother and more stable VFOs. An upgrade would be nice.
In part one of this restoration, we tackled the Ten Tec Omni C’s two most glaring problems: garbled signals on receive and blowing fuses when the radio was switched to the 30-Meter band. I could now receive and transmit signals in almost all the band switch positions, albeit with varying sensitivity and power output. It had been quite a chase so far, and the remaining repairs would prove equally challenging.
I purchased a Ten Tec Omni Series C transceiver about a year ago for my collection. At the time, I was in the middle of several other projects, and didn’t get to it until just recently. I had been using an Omni D, but it still needs work and I thought the “C” would be a nice upgrade.
In the last post, I described a used Ten Tec Triton IV and addressed the most immediate issues. I also mentioned making a cosmetic restoration, but after using it in the shack for an evening, it was apparent there were other problems. The “Offset Tuning” (OT) LED didn’t work, and more seriously, the transceiver didn’t always mute in transmit. Strange sounds issued from the speaker at times.
eBay has provided a lot of entertainment (and used equipment!) over the last few months, and after the purchase and restoration of a Ten Tec Century 21, I started looking for a Triton IV. This was the first radio I purchased new in 1978. I really enjoyed it and wanted to own one again. It didn’t take long. I ended up having two in the shop at almost the same time — one for my shack, and one for a fellow ham.
Over the years, Ten Tec has released a surprising number of CW (continuous wave or Morse Code) Keyers for Amateur Radio use. There have been two basic designs, single paddle and double or imabic paddle models. Released in about 1975, the Model 670 is a single paddle version, intended for use with the Century 21 CW transceiver.
The Ten Tec Triton I/II transceivers were released in the mid-1970’s and marked a milestone in High Frequency (HF) radios. With coverage for the 80, 40, 20, 15 and 10-meter amateur radio bands, 50 to 100 watt output on SSB and CW, they may have been the first affordable, fully solid-state models.
Restoring the Freshman Masterpiece AM radio was a lot of fun, but using batteries wasn’t. They’re convenient for testing, but expensive for regular use. The “B” battery alone uses ten 9-volt batteries, and that’s over $20 per set. There are battery simulators available for old tube radios, but they’re not cheap either, and where’s the fun in just buying a plug-in power supply? Wouldn’t it be cooler to use solar power and a 12-volt rechargeable battery?