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Copyright © 2004 CBTricks.com
Pride DX300
CHAPTER 3
Another set of contacts on the
(RL1)
4PDT relay switches the cathode circuit of the tube to ground when the
amplifier goes into the "on the air" condition. When not transmitting, two 18K, 2W resistors
(R46, R47)
provide a
cathode blocking bias that prevents the tube from pulling current. The two 270ohm, 2W resistors
(R48, R49)
that
are in series with the cathode line provide some additional bias during the
TUNE
mode, causing a loss in power
gain and making it easy to tune up at lower power. These resistors are shorted out by a section of the
TUNE/STANDBY/OPERATE
switch when in the
OPERATE
mode.
Figure 3-41 Cathode Circuit
The
(RL2)
DPDT relay on the main R.F. board is used solely for switching the receiver preamp in and out of the
antenna circuit. It is controlled by both the
RECEIVE
switch on the front panel and the grounding contact on the
(RL1)
4PDT relay.
Figure 3-42 Receiver Preamp Circuit
Содержание Amp Series
Страница 1: ...PRIDE DX 300 Service Manual Amp Series Copyright 2004 CBTricks com Version 1 0...
Страница 19: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 0 Low Voltage Supply PCB...
Страница 20: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 1 High Voltage Supply PCB Board 1...
Страница 21: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 2 High Voltage Supply PCB Board 2...
Страница 22: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 3 Wattmeter PCB...
Страница 23: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 4 RF Input and Control PCB...
Страница 24: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 5 Safety Interlock PCB...
Страница 25: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 6 PCB Trace Layouts...
Страница 26: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 PCB Trace Layouts Cont...
Страница 27: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 7 Chassis Layouts Front and Rear...
Страница 28: ...32 Copyright 2004 CBTricks com Pride DX300 CHAPTER 5 5 8 Chassis Layouts Top and Bottom...
Страница 38: ...32 Copyright 2004 CBTricks com...