▼ Menu

EH90

Sensibly equivalent to:
6CS6
See also:
Valves and their Habits - Locked Oscillator Discriminator - New Mullard Television Valves - Valves for Dual Standard TVs Advert - EH90 Locked Oscillator and PL500 Advert
    
Extras ▼

 

The EH90 is an indirectly heated heptode mixer from the 1950's. In the early 1960's Mullard designed circuits for the EH90 so it could act as an FM demodulator for 6 MHz inter-carrier sound.
This exhibit from Mullard features the later yellow paint to mark the envelope. See Mullard for why the yellow paint was used.
See EH90 for full details.
The side view of the anode shows the wire grids.
The thin glass tube envelope is 17 mm in diameter, and excluding the B7G base pins is 46 mm tall.
References: Datasheet & 1040. Type EH90 was first introduced in 1954.

 

Pin Connections
B7G
1
2
3
4
5
6
7
g1
k,g5
h
h
a
g2,g4
g3

 

Absolute Maximum Operating Conditions
Heptode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
6.3
0.3
100
30
-1
0.75
1.1
1M
0.95
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated September 07, 2016.
Return to Main Index