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7R7

Sensibly equivalent to:
CV900
    
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The 7R7 is a screened pentode and double diode. This is the classic valve design for AGC rectification, signal detection and first audio amplifier. The alternate use for the pentode is as an IF amplifier as it is of a semi variable-μ type.
The 14R7 has a 12.6 Volt heater.
Made in England by STC under the Brimar brand name.
The wide glass tube envelope is 28 mm in diameter, and excluding the B8B base pins is 56 mm tall.
References: Data-sheet & 1040. Type 7R7 was first introduced in 1942. See also 1942 adverts.

 

Pin Connections
B8B
1
2
3
4
5
6
7
8
h
a
a(d2)
a(d1)
g2
g1
k
h

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
6.3
0.3
250
100
-1
6.2
1.6
1M
2.3
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated August 06, 2020.
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