COMPONENT MAINTENANCE MANUAL
1152682
Page 105
Oct 27/06
© Honeywell International Inc. Do not copy without express permission of Honeywell.
23-24-02
(b)
Test Procedures
1
Connect the transmitter unit BNC output port to the spectrum analyzer using a
co-axial cable (preferably low-loss) of known db loss and place the 30 dBm
attenuator in between so that the power rating of the spectrum analyzer is not
exceeded, resulting in damage to the equipment.
2
Set the spectrum analyzer as follows:
•
Center Frequency: 121.5 MHz
•
Span: 1 MHz
•
Resolution Bandwidth: 100 kHz
•
Video Bandwidth: 100 kHz
•
Sweep Rate: 50 ms
•
Max Hold A: On
•
Reference Level: 10 dBm
3
Activate the transmitter unit by moving the switch on the transmitter unit from
the OFF position to the TX position.
4
Capture the 121.5 MHz signal on the analyzer, use the PEAK SEARCH to
locate the spectral peak and read the displayed amplitude on the analyzer
screen. Determine the actual 121.5 MHz signal power output by adding the
following together:
•
the amplitude measured on the analyzer
•
the 30 dBm loss of the attenuator
•
the previously measured loss of the coaxial cable(s)
•
the Spectrum Analyzer Correction Factor for this frequency
a
The Spectrum Analyzer Correction Factor can be found on a label
attached to the spectrum analyzer. If no such label is found, refer to
section 4 of RESCU 406 AF User Guide and Reference Manual 6C-520,
to determine the correction factors.
b
Record this value as the 121.5 MHz output power, which shall be greater
than +20.0 dBm.
5
Repeat this procedure for the 243 MHz signal, changing only the Centre
Frequency setting on the spectrum analyzer to 243 MHz. Make sure the
Spectrum Analyzer Correction Factor for 243 MHz is used. All other settings
remain the same. Record the value for the 243 MHz output power, which shall
be greater than +20.0 dBm.
6
Place the switch on the transmitter unit back to the OFF position.
