WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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20 W Stereo Audio Amplifier
10.1.3 6CA4
The 6CA4 is a 9-pin rectifier tube used in power supplies for a variety of products having
moderate dc requirements. The pin layout is shown in Figure 10.5. This tube, like other power-
handling devices, should be adequately ventilated. Typical rating chart is shown in Figure 10.6.
Grid #1 (control grid) voltage –33 V
Peak AF grid #1 to grid #1 voltage 67 V
Zero signal cathode current 62 mA
Maximum signal cathode current 95 mA
Effective load resistance (plate to plate) 12.5 k
Ω
Maximum signal output 18.5 W
Note:
1 Obtained from taps on the primary winding of the output transformer. The taps are located on each side
of the center tap (B+) so as to apply 50% of the plate signal voltage to grid #2 of each output tube.
Table 10.2 Key Parameters of the 6973
Figure 10.5 Terminal pinout of the 6CA4.
Figure 10.6 6CA4 rating chart.