A friend lent me his Collins TCS-12 transmitter so I could make this video. I had a good look around this well-built TX. Join me for a look, if you will.
The Collins TCS-12 is a particularly interesting piece of American Second World War military radio equipment. Manufactured by the Collins Radio Company of Cedar Rapids, Iowa, it was designed for the US Navy and became well regarded for its robust construction and performance.
It is a proper piece of vintage military radio engineering, built to withstand demanding conditions aboard ships and in mobile installations.
History and purpose
The TCS series was developed for the US Navy during the early 1940s. The equipment was intended for:
- PT boats and other small naval craft.
- Landing ships and landing craft.
- Shore communication stations.
- Mobile military communications.
The TCS-12 was manufactured during approximately 1941–1945. Collins also used other manufacturers, including Magnavox, to help meet wartime production requirements.
Technical specifications
| Specification | Details |
|---|---|
| Manufacturer | Collins Radio Company |
| Model | TCS-12 |
| Transmitter designation | COL-52245 |
| Frequency coverage | 1.5–12 MHz |
| Frequency bands | 1.5–3, 3–6, 6–12 MHz |
| Transmitter valves | 7 |
| CW output | Approximately 25 watts |
| AM output | Approximately 10 watts |
| Operating modes | AM voice and CW |
| Frequency control | VFO or crystal |
| Construction | Heavy metal chassis |
These are the commonly published original specifications. Actual performance depends on the particular transmitter and its condition.
The transmitter
The transmitter is a substantial piece of equipment, weighing approximately 49 lb (22 kg). It uses seven valves, including 1625 output valves, and has a built-in variable frequency oscillator (VFO). It can operate using:
- Continuously variable VFO control.
- Crystal-controlled frequencies.
- Amplitude-modulated speech.
- Continuous-wave Morse transmission.
One particularly interesting feature is its push-pull modulator arrangement, which provides proper anode modulation for AM transmission.
The matching receiver
The matching receiver carries the designation CMX-46159. It covers the same 1.5–12 MHz frequency range and uses a seven-valve superheterodyne circuit. It has provision for both crystal-controlled and variable-frequency operation. The transmitter and receiver were designed to work together as a complete communications station.
Power supply
The original equipment required several different DC voltages:
- 12 volts for valve heaters and associated circuits.
- 220 volts DC for receiver and transmitter circuitry.
- 400 volts DC for the transmitter's high-voltage supply.
The original mobile power arrangements used motor-generator units, known as dynamotors, to generate the necessary high voltages from a 12-volt supply. There were also alternative power arrangements for fixed installations.