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// Workers AI · dad joke modeWhat did Fetron say to Fetron? Fetron-ically yours.

From Wikipedia, the free encyclopedia

The Fetron was a range of solid-state, plug-compatible replacements for vacuum tubes (valves).

Fetrons were manufactured by Teledyne Semiconductor from 1967; primarily as a low-maintenance and low-power swap-in to replace vacuum tubes, which were becoming increasingly obsolete and difficult to source with the widespread use of solid-state electronics. They were used in large numbers in telephone exchanges.[1][2] Vacuum tubes use significant amounts of power to maintain operating temperature, and large installations had substantial air-conditioning requirements; replacing them with fetrons was expected to reduce cooling and maintenance costs.[3]

A typical fetron consisted of a cascode configured pair of JFETs, some simple RC networks to control the device characteristics, and a fuse. The device was mounted in a metal tube with a base that has the same pin-out as the vacuum tube that it replaced.

Use

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Fetrons were used to upgrade oscilloscopes and similar test equipment.[4] They were used in specialist audio amplifiers such as the Mesa Boogie Mark Series.

Fetrons occasionally appear on eBay and similar, and are collected by vintage radio enthusiasts.

Other manufacturers

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Western Electric produced the conceptually similar Hybrid Integrated Network devices, which were used in their own telephone equipment.[1]

References

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  1. 1 2 Storr, Phil. "The Fetron". Archived from the original on 2 March 2016. Retrieved 26 June 2016.
  2. ↑ Palix, Olivier. "TR1011". Radiomuseum. Retrieved 26 June 2016.
  3. ↑ FETRON solid state vacuum tube replacement (PDF). Teledyne Semiconductor. 1973. Archived from the original (PDF) on 27 February 2016. Retrieved 26 June 2016.
  4. ↑ "TUBESTERS by Skytec and FETRONS by Teledyne Semiconductor" (PDF). qsl.net. Retrieved 26 June 2016.