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QP22BSensibly equivalent¶ to:See also:
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The QP22B is a wonderful valve. It is a battery double pentode, designed for quiescent push pull class B audio amplification. The total power output is 1 Watt and was aimed at driving a loudspeaker, quite a luxury when battery powered.The valve can be operated with automatic bias obtained from a resistor in the common HT negative lead. Such a resistor should be bypassed at signal frequencies by a 50 µF capacitor. For minimal distortion the total anode current (both anodes) should not fall below 3 mA and the screen grid supply should be 120 Volts.The classic envelope is 38 mm in diameter and, excluding the B7 base pins, is 94 mm tall.References: 1043. Type QP22B was first introduced in 1938. See also 1938 adverts. |
Pin Connections
| 1 | 2 | 3 | 4 | 5 | 6 | 7 |  g1(2) | g1(1) | a(1) | f | f | g2 | a(2) |
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Absolute Maximum Operating Conditions¶
| Vh | Ah | Va | Vs | Vg | mAa | mAs | Pout |
| 2.0 | 0.3 | 135 | 135 | -11.7 | 3.8 | 0.5 | 1.33W |
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Updated December14, 2012.
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