| CV51 tuning indicator
 |
This valve measures 102x40mm
overall and has an octal base with one pin omitted. |
The markings 48P51 appear on
the side of the valve. The prototype for this valve is E1320.

| Heater voltage |
6.3V |
| Heater current |
0.3A |
| Max anode voltage |
250V |
| Max target voltage |
250V |
| Pin |
Function |
| 1 |
n/c |
| 2 |
Heater |
| 3 |
Anode |
| 4 |
Target |
| 5 |
Grid |
| 6 |
no pin |
| 7 |
Heater |
| 8 |
Cathode |
|
 |