Couple of problems with this substitution... the bp1 has a 14 pin base vs 11 pin for the kp1.
The neck of the bp1 is fatter, and may not fit in a kp1 neck clamp. I don't have any electrical data, but since the bp1 is shorter than the kp1, it
may offer less deflection sensitivity. In a TV-37, you might not get a full sized picture.
3BP1 (14 pin)
14,1 Heater
2 Cathode
3 Grid
5 Focus
9 Anode
7,8 vert deflection
10,11 horiz deflection
3KP1 (11 pin)
11,1 Heater
2 Grid
3 Cathode
4 Focus
7 Anode
8,9 vert deflection
5,6 horiz deflection
This article shows a 3RP1 (12 pin) in a TV-37:
http://www.electronixandmore.com/tel...lot/index.html
Here is my TV-37 with a 3KP1 substituted for a 3KP4 (best choice, if you can find one):
Good luck,
jr