VHF Tranceiver
Figure 006A
R 1EFF : 051-099, 106-149, 201-299, 301-399, 1 23-12-00Page 23 1401-499, 1Aug 01/05 1 1 1CES 1
VHF Tranceiver
R Figure 006B
R 1EFF : 151-199, 1 23-12-00 Page 24
1 1 May 01/05
1 1
1CES 1
R **ON A/C 051-099, 106-149, 201-299, 301-399, 401-499,
1 VHF transceiver face
_
The face features :
(Ref. Fig. 006A)
-Two jacks (PHONE and MIC)
-
A TEST pushbutton switch
-
A red/green warning light: LRU STATUS
-
A red indicator light: CONTROL FAIL
-
A red warning light: ANTENNA FAIL
-
A handle
-An identification plate.
**ON A/C 151-199,
1 VHF transceiver face
_
The face features :
(Ref. Fig. 006B)
-two jacks (PHONE and MIC)
-
a self-test pushbutton
-
a LCD screen to display messages in simple language in one of four modes (normal operation, BITE display, maintenance, S/W loading).
-two pushbutton switches.
-a handle
**ON A/C 001-049, 101-105,
2 VHF transceiver back
_ The back comprises three connectors to enable connection with:
-
The automatic test circuits (Top Plug TP)
-
The peripheral systems (Middle Plug MP)
-
The antenna and the power supply circuits (Bottom Plug BP).
R **ON A/C 051-099, 106-149, 151-199, 201-299, 301-399, 401-499,
2 VHF transceiver back
_ The back comprises three connectors to enable connection with:
-vendor specific test-equipment (Top Plug TP)
-
The peripheral systems (Middle Plug MP)
-
The antenna and the power supply circuits (Bottom Plug BP).
1EFF : ALL 1 23-12-00Page 25 1 1 Aug 01/05 1 1 1CES 1 **ON A/C 001-049, 051-099, 101-101, 201-203,
(2) Characteristics The VHF transceiver complies with the standards defined in ARINC 716. The transmission and reception of coded messages between the various control units (CFDIU, RMP) comply with ARINC 429. The transceiver operates within the frequency range between 118.000 and 136.975 MHz with 25 KHz spacing between channels (it has a possibility of 760 channels).
R **ON A/C 102-149, 151-199, 204-299, 301-399, 401-499,
(2) Characteristics The VHF transceiver complies with the standards defined in ARINC 716. The transmission and reception of coded messages between the various control units (CFDIU, RMP) comply with ARINC 429. The transceiver operates within the frequency range between 118.000 and 136.975 MHz with 8,33 KHz spacing between channels (it has a possibility of 2278 channels).
**ON A/C ALL
(3) Operation
**ON A/C 001-049, 101-105,
(a) General operation The transceiver consists of five sections:
-Transmit/Receive (T-R) switch and filter
-Receiver
-Receiver/synthesizer
-Transmitter synthesizer - I/Q modulator - I/Q modulator filter
-Transmitter.
In Receive mode:
The VDR (VHF Data Radio) RF module amplifies and converts RF
signal received by the antenna into intermediate frequency (I-F)
and analog signals to make it processed by the digital-signal
processor (DSP) of the main processor module.
In Transmit mode:
The RF module modulates the analog signals provided by the DSP
section onto RF signals for transmission through the antenna.
1EFF : ALL 1 23-12-00Page 26 1 1 Aug 01/05 1 1 1CES 1 The main processor module sends selection voltage to the transmitter and control signal to the receiver synthesizer to control the transmit/receive switch and filter. The received signal in the transmit/receive switch and filter is checked by the main processor preselector tune coming through the receiver. Channel spacing selection and DSP automatic gain control (AGC) from the main processor module control IF and audio outputs produced in the receiver. The synthesizer data from the main processor controls the receiver synthesizer and the transmitter synthesizer. The receiver synthesizer data from the main processor provides the first local oscillator (L.O) frequency output to the transmit/receive switch and filter. After the VDR detects that the microphone is in the transmit position for a duration longer than 30 seconds, 1KHz interrupted tone (1/2 second on, 1/2 second off) is emitted for five seconds via the audio/sidetone output. After a total of 35 seconds, the VDR turns off the transmitter and the 1KHz interrupted sidetone. To reactivate the transmitter, the microphone PUSH-TO-TALK button must be released and then rekeyed. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：A320飞机维护手册 AMM Communications 通讯1(68)
