▼ Menu

W149

Sensibly equivalent to:
7B7
    
Extras ▼

 

The W149 is a variable μ amplifier pentode. It was most probably used as as an AGC controlled RF or IF amplifier in superhet receiver.
The visible cylinder looks to be the screen and not the anode.
The wide glass tube envelope is 29 mm in diameter and, excluding the B8B base pins, is 56 mm tall.
References: 1040.

 

Pin Connections
B8B
1
2
3
4
5
6
7
8
h
a
g2
g3
s
g1
k
h

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
6.3
0.15
250
100
-3
8.5
1.7
0.75M
1.75
Updated January 23, 2018.
shape:wide.glass.tube construction:all.glass type:pentode age:1940.1950 base:b8b heater:6.3v pins:8 pin:1.h pin:2.a pin:3.g2 pin:4.g3 pin:5.s pin:6.g1 pin:7.k pin:8.h
Return to Main Index