WhitakerAudio AM/FM Stereo Tuner 2012, Сборка и руководство пользователя

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Because of the special structural arrangement of the 6BE6, a change in signal grid voltage
produces little change in cathode current. Consequently, an RF voltage on the signal grid
produces little modulation of the electron current flowing in the cathode circuit. This feature is
important because it is desirable that the impedance in the cathode circuit produce little
degeneration or regeneration of the signal frequency input and intermediate frequency output.
Another important feature is that, because the signal grid voltage has little effect on the space
charge near the cathode, changes in AVC bias produce little change in the oscillator
transconductance and in the input capacitance of grid #1. There is, therefore, little de-tuning of the
oscillator by AVC bias.
The 6BE6 operating characteristics curves with self-excitation are diagrammed in Figure
10.6. E
k
is the voltage across the oscillator coil section between the cathode and ground. E
g
is the
oscillator voltage between the cathode and grid.
Table 10.3 Key Parameters of the 6BE6
General Characteristics
Heater (ac/dc) 6.3 V, 0.3 A
Heater-cathode voltage
Peak value ±200 V max.
Average value 100 V max.
Direct interelectrode capacitance, unshielded (approx.)
Grid #3 to plate 0.30 pF max.
Grid #3 to grid #1 0.15 pF max
Grid #1 to plate 0.01 pF max.
Grid #3 to all other electrodes 7 pF
Grid #1 to all other electrodes 5.5 pF
Plate to all other electrodes 8 pF
Grid #1 to cathode and grid #5 3 pF
Cathode and grid #5 to all other electrodes except grid #1 15 pF
Converter, Maximum Ratings (Design-Maximum Values)
Plate voltage 330 V
Grid #2 and grid #4 (screen grid) voltage 110 V
Grid #2 and grid #4 (screen grid) supply voltage 330 V
Cathode current 15.5 mA
Plate dissipation 1.1 W
Grid #2 and grid #4 (screen grid) input 1.1 W
Grid #3 voltage
Negative bias value 55 V
Positive bias value 0 V
Heater-cathode voltage
Peak value 200 V
Average value 100 V