2-4
VHF Amplifier Instruction Manual VT-3 132 - 174 MHz
2.5.3
VSWR Overload
The VSWR overload circuit protects the VT-3/150 Amplifier from excessive antenna VSWR by
reducing the amplifier's gain (output power) when an overload condition occurs. The VSWR
overload circuit (R14, R37, R39, R40, U2a, and Q6) is an extension of the VSWR sense circuit and
operates the same as the VSWR sense open collector circuit. The VSWR Overload Adjust
potentiometer (R37) reduces the voltage level of the VSWR Alarm Setpoint. The voltage set by
R37 is the compared to the output power alarm setpoint by op-amp U2a which then drives
transistor Q6. When transistor Q6 turns on, signaling an overload condition, resistor R14 is
grounded which reduces the output power setpoint. Reducing the output power setpoint lowers the
VT-3/150 Amplifier's gain and protects the amplifiers from excessive current draw resulting from
high antenna VSWR.
The VSWR overload circuit's range of adjustment depends on the setting of the VSWR Alarm
Adjust potentiometer (R36). The VSWR overload transistor Q6 can be activated at the same point
at which the VSWR alarm becomes active or the VSWR overload circuit can be disabled by turning
R37 completely counterclockwise.
Содержание VT-3/140-SWA2
Страница 20: ...4 2 VHF Enhanced Transmitter Instruction Manual VT 3 132 174 MHz This Page Intentionally Left Blank ...
Страница 22: ...5 2 VHF Enhanced Transmitter Instruction Manual VT 3 132 174 MHz This Page Intentionally Left Blank ...
Страница 28: ...vi Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...
Страница 62: ...4 2 Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...
Страница 64: ...DEDANIELS ELECTRONICS 5 2 Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...
Страница 74: ...DEDANIELS ELECTRONICS 5 12 Transmitter Main Board Instruction Manual This Page Intentionally Left Blank ...
Страница 106: ...6 2 Audio Processor Board Instruction Manual This Page Intentionally Left Blank ...
Страница 110: ...ELECTRONICS LTD DANIELS TM 7 4 Audio Processor Board Instruction Manual This Page Intentionally Left Blank ...
Страница 114: ...8 4 This Page Intentionally Left Blank ...
Страница 120: ...9 10 This Page Intentionally Left Blank ...
Страница 123: ...ELECTRONICS LTD DANIELS TM Audio Processor Board Instruction Manual 9 13 This Page Intentionally Left Blank ...
Страница 126: ...ELECTRONICS LTD DANIELS TM 9 16 Audio Processor Board Instruction Manual This Page Intentionally Left Blank ...
Страница 128: ...10 2 Audio Processor Board Instruction Manual This Page Intentionally Left Blank ...
Страница 134: ...This Page Intentionally Left Blank ...
Страница 150: ...DEDANIELS ELECTRONICS 4 4 VHF Amplifier Instruction Manual VT 3 132 174 MHz This Page Intentionally Left Blank ...
Страница 152: ...4 6 VHF Amplifier Instruction Manual VT 3 132 174 MHz This Page Intentionally Left Blank ...
Страница 157: ...VHF Amplifier Instruction Manual VT 3 132 174 MHz 6 1 6 REVISION HISTORY ISSUE DATE REVISION 1 Jul 97 First Issue ...
Страница 158: ...6 2 VHF Amplifier Instruction Manual VT 3 132 174 MHz ISSUE DATE REVISION ...
Страница 168: ...1 6 Enhanced AM FM Synthesizer Instruction Manual OS R T 3 A H 29 470 MHz This Page Left Intentionally Blank ...
Страница 178: ...2 10 Enhanced AM FM Synthesizer Instruction Manual OS R T 3 A H 29 470 MHz This Page Intentionally Left Blank ...
Страница 186: ...3 8 Enhanced AM FM Synthesizer Instruction Manual OS R T 3 A H 29 470 MHz This Page Intentionally Left Blank ...
Страница 222: ...5 16 Enhanced AM FM Synthesizer Instruction Manual OS R T 3 A H 29 470 MHz This Page Intentionally Left Blank ...
Страница 228: ...iv VHF Transmitter Channel Designation Tables VT 3 132 174 MHz This Page Intentionally Left Blank ...
Страница 236: ...1 8 VHF Transmitter Channel Designation Tables VT 3 132 174 MHz This page intentionally left blank ...
Страница 261: ...VHF Transmitter Channel Designation Tables VT 3 132 174 MHz 5 1 5 REVISION HISTORY ISSUE DATE REVISION 1 May 98 Issue 1 ...
Страница 262: ...5 2 VHF Transmitter Channel Designation Tables VT 3 132 174 MHz This Page Intentionally Left Blank ...