▼ Menu

U149

Sensibly equivalent to:
7Y4 U82
See also:
Pioneers of HT Rectifiers
    
Extras ▼

 

The U149 full wave rectifier is almost identical to the American Type 7Y4.
The maximum reservoir capacitor is 40 µF and the minimum series resistance, for current limiting, is not given in the literature.
The two anodes mounted one above the other on the common cathode.
The anodes are asymmetric in shape and the lower is rotated by 180 degrees relative to the upper anode.
The wide glass tube envelope is 28 mm in diameter and, excluding the B8B base pins, is 55 mm tall.
References: Datasheet & 1040. Type U149 was first introduced in 1950.

 

Pin Connections
B8B
1
2
3
4
5
6
7
8
h
-
a(2)
-
-
a(1)
k
h

 

Absolute Maximum Operating Conditions
Rectifier
Vh
Ah
Va
mAa
6.3
0.5
325
70
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated January 20, 2018.
shape:wide.glass.tube construction:all.glass type:rectifier.fw age:1940.1950 base:b8b heater:6.3v pins:8 pin:1.h pin:2.- pin:3.a(2) pin:4.- pin:5.- pin:6.a(1) pin:7.k pin:8.h
Return to Main Index