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VMS4

Sensibly equivalent to:
AC/SGVM AS4125 CV1165 MVSPen VP4
See also:
Some Important British Valves - M-OV's Screened Grid Valves
    
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The VMS4 variable μ screened tetrode design dates from 1931. It was designed for RF and IF amplification in broadcast superhet receivers. This exhibit is a later example employing the shouldered envelope to allow for a mica sheet to provide support at the top ov the envelope. The first VMS4 valves followed the pattern of the first single ended SG valves in having a waist above the base cap that extended to the point where the screen grid began within the glass. Thus it could be mounted horizontally through a metal plate or chassis for maximum screening. See S215.
The printed Osram name.
The classic envelope is 45 mm in diameter and, excluding the B5 base pins, is 119 mm tall.
References: Datasheet & 1005 Type VMS4 was first introduced in 1931.

 

Pin Connections
B5
1
2
3
4
5
tc
g2
g1
h
h
k
a

 

Absolute Maximum Operating Conditions
Tetrode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
4.0
1.0
200
80
0.0
14.0
3.0
0.45M
2.4
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated March 07, 2015.
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