▼ Menu

UCH81

Sensibly equivalent to:
10C14 19D8 X119
    
Extras ▼

 

The UCH81 is a triode oscillator and heptode mixer for use as a frequency changer in superhet receivers. This exhibit is British Made.
The 100 mA heater is designed for universal mains sets, and this is why the anode voltage is 200 maximum.
The mesh screen hides most of the details but through the cap can be seen the triode section at the top. Also visible is the screening plate that shields pin 6 - the main anode.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 60 mm tall.
References: Datasheet & 1040. Type UCH81 was first introduced in 1953.

 

Pin Connections
B9A
1
2
3
4
5
6
7
8
9
g2,g4
g1
k,g5,s
h
h
a(h)
g3
a(t)
g1(t)

 

Absolute Maximum Operating Conditions
Heptode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
19.0
0.1
200
119
-2.6
3.7
8.1
1.0M
0.78

 

Absolute Maximum Operating Conditions
Triode
Va
Vg
mAa
100
0.0
13.5
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated January 29, 2016.
Return to Main Index