Talk:EL84

7189A
Dont forget the 7189A Tabby (talk) 22:20, 12 December 2007 (UTC)

Frame output?
What's a "frame output"? I suspect a translation from...something. --Wtshymanski (talk) 22:04, 24 June 2023 (UTC)


 * Frame output is the power device driving the vertical deflection coils in a CRT based display. It's partner is the line output which drives the horizontal deflection. 86.177.26.80 (talk) 16:04, 25 June 2023 (UTC)
 * Thanks. My elderly copy of Newnes' "Electronics Engineer's Reference Book" did not explain this alternative to what I knew as "vertical deflection". --Wtshymanski (talk) 01:15, 29 June 2023 (UTC)
 * ... and now it's gone from the article anyway. --Wtshymanski (talk) 01:19, 29 June 2023 (UTC)
 * It is not immediately clear which are the UK terms versus the US terms. In the 1950's, the UK used 'horizontal' and 'vertical' while the US used 'line' and frame'. Somewhere around the mid 1960's the two switched sides. Thank heavens the CRT is obsolete effectively resolving the problem. 86.177.26.80 (talk) 13:54, 30 June 2023 (UTC)

EL84, PL84 and EL86
This section has been removed as uncited.

Best research I can come up with is that the PL84 was specifically designed as a frame output pentode, and its design is based on the EL84, not that it is a variation of it. The EL86 was specifically designed for use in transformerless output stages. I can find no evidence that it is a PL84 with a 6.3 volt heater though as the characteristics are similar (but not the same) it is not impossible that the PL84 influenced its design as both appear to be designed for a lower anode voltage and higher current than the EL84.

Mazda Belvu did produce a 6.3 volt version of the PL84 but identified it as EL86F to distinguish from a real EL86 though it is however classed as an AF power output pentode but with no mention of its use in transformerless output deigns. 86.177.26.80 (talk) 16:40, 25 June 2023 (UTC)