|
Marconi MKT4 pentode.
 |
This 7 pin valve measures 132x55mm
overall. The 5 pin example measures 110x45mm overall and has a side connector on the base.
|
The 7-pin example is a pentode with the suppressor grid
connected internally to the cathode. However the Osram data indicates
it is a beam tetrode, a fact verified by examination of the 5-pin
example.
| Heater voltage |
4V |
| Heater current |
1A |
| Anode voltage |
250V |
| Anode current |
32mA |
| Screen voltage |
225V |
| Screen current |
4mA |
| Control grid voltage |
-13.5V |
| Amplification factor |
3 |
| Power output |
2.5W at 10% distortion |
| 1 |
Heater |
| 2 |
Cathode + suppressor grid |
| 3 |
Anode |
| 4 |
n/c |
| 5 |
Control grid |
| 6 |
Screen grid |
| 7 |
Heater |
| 1 |
Anode |
| 2 |
Control grid |
| 3 |
Heater |
| 4 |
Heater |
| 5 |
Cathode + beam plates |
Side
cap |
Screen grid |
|
 |
Data provided by Nick Vernon; 5-pin valve donated by Leo Lyndon, Radio and TV
Engineer, 1923 - 2006.
This file was last modified
15:51:06, Saturday November 12, 2011
