Fetron
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[edit]
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[edit]
Western Electric produced the conceptually similar Hybrid Integrated Network devices, which were used in their own telephone equipment.[1]
References[edit]
- ^ a b Storr, Phil. "The Fetron". Archived from the original on 2 March 2016. Retrieved 26 June 2016.
- ^ Palix, Olivier. "TR1011". Radiomuseum. Retrieved 26 June 2016.
- ^ FETRON solid state vacuum tube replacement (PDF). Teledyne Semiconductor. 1973. Archived from the original (PDF) on 27 February 2016. Retrieved 26 June 2016.
- ^ "TUBESTERS by Skytec and FETRONS by Teledyne Semiconductor" (PDF). qsl.net. Retrieved 26 June 2016.