The B65 is an audio double triode with a 6.3 Volt heater. The B36 is the same valve except for the 12.6 volt heater.
The Osram paper label.
The wide glass tube envelope is 28 mm in diameter, and excluding the IO base pins, is 71 mm tall.
References: Datasheet & 1040. Type B65 was first introduced¶ in 1948.
Pin Connections
IO |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |

|
g1(2) |
a(2) |
k(2) |
g1(1) |
a(1) |
k(1) |
h |
h |
Absolute Maximum Operating Conditions¶
Triode |
Vh |
Ah |
Va |
Vg |
mAa |
ra |
gm |

|
6.3 |
0.8 |
250 |
-0 |
3 |
7.7k |
1.6 |
Thanks to Frank Philipse for supplying the above PDF datasheet
|