The BL63 is an indirectly heated glass unmetallised double triode. Of low impedance with one grid taken to the top cap.
It was supplied to the UK RAF during the 1940'S for use in the R1155 receiver that was fitted to Lancaster and other aircraft. Its output fed the twin-needled Visual Indicator and one of these instruments was usually fitted on the top of the cockpit instrument panel.
Nowadays it is used in audio equipment as a non-direct replacement for ECC32’s although the in circuit current is slightly different and the pin out is different.
Testing the BL63 can be complicated due to disparity. Testing data given below.
CHARACTERISTICS
Heater voltage 6.3 V
Heater current 1.27 A
DIMENSIONS
Maximum seated height 116 mm
Maximum diameter 45 mm
Base Octal
Net weight 50 g
PIN CONNECTIONS
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
T/C
|
No connection
|
Heater
|
Anode 2
|
Cathode 2
|
Grid 1
|
Anode 1
|
Heater
|
Cathode 1
|
Grid 2
|
RATINGS
Maximum Operating conditions
Vf
|
Af
|
Va
|
Vg
|
m/Aa
|
ra
|
gm
|
µ
|
6.3
|
1.27
|
250
|
-16
|
7
|
2860
|
4.2
|
12
|
Typical Operating conditions
Vf |
Af |
Va |
Vg |
m/Aa |
ra |
gm |
µ |
6.3 |
1.27 |
150 |
-12 |
7 |
2860 |
2.5 |
12 |
TESTING CONDITIONS
Vf |
Af |
Va |
Vg |
m/Aa |
gm |
6.3 |
1.27 |
200 |
-12 |
12 |
2.5 |
Before the test adequate time should be allowed for the test chassis to attain a constant temperature. Testing should be applied to each half of the valve.
|