Tennelec

Tennelec was a US electronics company founded in the early 1960s by Edward Fairstein Edward Fairstein websitein Oak Ridge, Tennessee. The company came to prominence producing instrumentation for nuclear studies and later, programmable scanning radios.

The TC-200 amplifier was a successful early design that established Tennelec as a leader in the nuclear instrumentation field. Following on the heels of the TC-200 success, the company developed additional components necessary for precise nuclear measurement, including detectors and particle counters.

Tennelec also manufactured innovative scanning radios in the 1970s. The first programmable radio scanner, designed by Peter Pflasterer, was the Tennelec MCP-1.

Prior to the MCP-1, scanners were manually programmed by inserting a series of hand-cut crystals tuned for different frequencies. The scanner would then switch between the frequencies, stopping when the user pressed a switch.

With the MCP-1 the user selected the frequencies they wanted to monitor by setting them up using binary coded decimal entered via sixteen switches on the front panel. The system could cycle through the selected frequencies until stopped. The advantage was that the system could be set up to monitor different sets of frequencies, police one night, fire departments the next.

The scanner was released at the Winter 1976 Consumer Electronics Show in Chicago. The system was a hit, and was soon picked up for Radio Shack. To help users get started, Radio Shack also purchased thousands of copies of Police Call, a guide to various radio frequencies. Two similar models followed, the MS-1 and MS-2.

Partly due to poor quality control of their scanner line, Tennelec filed for bankruptcy soon after introducing their latest radio models. By this point other manufacturers, in particular SBE and Regency and Electra, had already introduced their own programmable models.