NTX VHF FM Series Remote Mount Transceiver
SM28 Installation and Operation Manual
May 9, 2012 Rev: 5.00
Page 2-4
ENG-FORM: 805-0100.DOTX
CONFIDENTIAL AND PROPRIETARY TO ANODYNE ELECTRONICS MANUFACTURING CORP.
2.3.7 Post-Installation
Checks
2.3.7.1 Voltage/Resistance
Checks
Do not attach the transceiver until the following conditions are met.
Check the following:
a) P101
pins
<5>
and
<6>
for +28 Vdc relative to ground.
b) P101
pins
<8>
and
<20>
for continuity to ground (below 0.5
Ω
).
Ensure that the antenna is disconnected for the following test or erroneous readings may be
obtained.
c)
Radio coax connector for continuity to the antenna coax connector (shield and center
conductor) and for open circuit from the center conductor to ground and open circuit from the
center conductor to the shield.
2.3.7.2
Power On Checks
a)
Install the transceiver and power up the
ship’s
systems. Turn on the control head.
Check the operation of all front panel controls. Adjust brightness and volume levels as
required.
b)
Check all transmit and receive functions. Ensure the RX/TX status indicator lights green when
keying the radio to transmit and amber when receiving.
c)
Check the SCAN function.
Note:
You may be unable to hear the received audio if the tones do not match those set in the radio.
To avoid any confusion, set the tones to OFF (via the Status Edit mode) during scanning so
that all channels will be heard.
d)
Check the antenna feedline at the R/T with a through-line wattmeter and suitable frequency
elements to ensure correct antenna matching. Reflected power in excess of 25% represents a
serious problem, and should be investigated carefully, or serious RFI and system interference as
well as possible radio damage may result. A VSWR measurement over 3.0:1 represents a
significant loss in signal power to the antenna. Check that forward power is to specifications over
the frequency band of the radio.
2.3.8 Post-Installation
EMI
Tests
The purpose of this test is to identify any interference that the transceiver may cause with existing
aircraft systems. The transceiver should be tested in accordance with the Installation Approval Test
Procedure (see section 2.5) and the test results documented on the record sheets.
