▼ Menu

Z77

Sensibly equivalent to:
6AM6 6F12 8D3 CV138 CV4014 EF91 HP6
See also:
EF91 - not the valve that won the war - Television RF Valve Development - Valves and their Habits - Valves for Bands III, IV & V - Physical Society Exhibition 1947 - Olympia Show 1947 - GEC CV4005 U78, CV4014 Z77 & CV4062 N78 Advert - The EF91 and the Blue Band
    
Extras ▼

 

The Z77 from M-OV was another designation for the ubiquitous EF91 of the late 1940s and here it carries the professional GEC label.
The GEC brand label. Above the top mica is a screen and also heat dissipating fins on the control grid supports.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 46 mm tall.
References: Data-sheet & 1040 Type Z77 was first introduced in 1947. See also 1947 adverts.

 

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

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
6.3
0.3
250
250
-2
10
2.5
1M
7.6
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated December14, 2020.
Return to Main Index