12BY7A

The 12BY7A  (European: EL180) (P/N 154-047,154-0047-00) is a miniature 6.5 W power pentode vacuum tube.

Both the 12BY7 (1951) and the slightly improved 12BY7A (1954/1955) are all-glass types with a B9A (Noval) miniature 9-pin base and share the EIA 9BF pinout with a number of other miniature pentode tubes of the era.

Aged/Checked/Matched Pair Details
Used in	Tek Part#	S/N Range
531, 533, 535, 536, 541, 543, 545, 555	157-0053-00	?
106	157-0115-00	Note 1

Note 1: Made obsolete soon after the number was allocated.

Reference:

Tube aging procedure / Selection and checking procedure

Data sheets and Links

9BF socket diagram

• General Electric 12BY7A data sheet
• 12BV7, 12BY7, 12BY7A @ Wikipedia
• 12BY7 / 12BY7A / EL180 @ radiomuseum.org

Used in

• the output stage of the 1121
• the first stage of the 535, 545A, and 555

Some instruments using part 12BY7A

Instrument	Manufacturer	Class	Model	Description	Introduced
106	Tektronix	Pulse generator	106	Pulse generator	1966
163	Tektronix	Plug-in	163	Pulse Generator Module	1952
3A75	Tektronix	Plug-in	3A75	4 MHz amplifier plugin	1964
3B5	Tektronix	Plug-in	3B5	Automatic time base plug-in	1966
524	Tektronix	Oscilloscope	524AD	TV waveform monitoring scope	1953
531	Tektronix	Oscilloscope	531	10 MHz oscilloscope	1954
533	Tektronix	Oscilloscope	533	15 MHz oscilloscope	1958
535	Tektronix	Oscilloscope	535	10 (15) MHz dual-timebase scope	1954
535	Tektronix	Oscilloscope	535	10 (15) MHz dual-timebase scope	1954
536	Tektronix	Oscilloscope	536	11 MHz X–Y oscilloscope	1957
541	Tektronix	Oscilloscope	541	30 MHz oscilloscope	1955
543	Tektronix	Oscilloscope	543	30 MHz oscilloscope	1958
545	Tektronix	Oscilloscope	545	30 (33) MHz oscilloscope	1955
545A	Tektronix	Oscilloscope	545A	30 (33) MHz oscilloscope	1959
549	Tektronix	Oscilloscope	549	30 MHz storage oscilloscope	1965
555	Tektronix	Oscilloscope	555	Dual beam 30 MHz scope	1959
75	Tektronix	Plug-in	75	4 MHz amplifier plug-in	1961

Pictures

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  RCA/Tektronix 12BY7As

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  RCA/Tektronix 12BY7As

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  RCA/Tektronix 12BY7As