RETMA tube designation

The Radio Electronics Television Manufacturers' Association was formed in 1953, as a result of mergers with other trade standards organisations.

It was principally responsible for the standardised nomenclature for American vacuum tubes.

American made tubes bear a RETMA designation to allow for easy cross-referencing. The RETMA tube designation does not incorporate the purpose of each tube in the designation. The Anglo-European Mullard-Philips tube designation does include tube use information in the designation.

In the case of a CRT, the second figure group indicates the type of phosphor the tube face was coated with.

Additional letters:

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