Mullard have designed their PY301 in smaller type than the equivalent U191 on the envelope. This suggests the PY301 was a copy of the U191.
This valve is a television efficiency diode. The function of the device is to enable the stored energy of the line scan coils to be returned to the supply rail during flyback.
The valve is rated at 5,000 Volts (PIV) and a peak current of 600 mA. The valve is unusual in that the top cap is taken to the cathode. This means a 5,000 volt heater cathode insulation.
The wide glass tube envelope is 28 mm in diameter and excluding the IO base pins it is 74 mm in length. Standard octal GT size.
Pin Connections
IO |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
tc |

|
- |
ic |
ic |
- |
a |
- |
h |
h |
k |
Absolute Maximum Operating Conditions
Diode |
Vh |
Ah |
mAa |

|
19.0 |
0.3 |
120 |
This exhibit was last updated on 06 February 2003 |
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