WD-11

The WD-11 vacuum tube, a triode, was introduced by the Westinghouse Electric corporation in 1922 for their Aeriola RF model radio and found use in other contemporary regenerative receivers (used as a detector-amplifier) including the Regenoflex and Radiola series.

The WD11 and "RCA-11"^[1] (and later simply named "11" by RCA^[2] and Philips/Miniwatt^[3]) have the following characteristics:

Socket:	UV4 (also known as WD-4-Pin)
EIA/RETMA base diagram:	4F
Description:	Detector Amplifier Triode
Filament:	Directly heated 1.1 V	0.25 A
Plate (anode) voltage:	90 V	135 V maximum
Grid voltage:	−4.5 V	−10.5 V
Plate current	2.5 mA	3.0 mA
Plate resistance:	15.5 kΩ	15 kΩ
Amplification Factor (mu):	6.6	6.6
Transconductance (gm or S):	0.425 mA/V	0.44 mA/V
Power output: (Po):	0.007 W	0.04 W[4]
Grid-plate Capacitance (Cga):	3.3 pF

1. RCA Receiving Tube Manual RC-13. 1937. p. 98.
2. RCA Receiving Tube Manual RC-14. 1940. p. 157.
3. "Miniwatt" Technical Data (6th ed.). Australia: The "Miniwatt" Electronics Division of Philips Electrical Industries Pty. Limited, N.S.W. 1958. p. 56.
4. "WD 11". Retrieved 7 January 2013.