Federal Signal Corporation Personnel Alerting System, Installation And Operation Instructions Manual

Page: 72 / 84

PRE-OPERATION CHECK-OUT AND TEST
72
6.3 Radio Transceiver Adjustment
Procedure
Note: This procedure previously
completed at factory. Only readjust if
radio re-alignment is required or if the
radio is being installed in the field.
A. Qualifications:
Requires a properly trained Radio
Technician.
B. Equipment Required:
1. Service Monitor
2. Oscilloscope
C. Setup:
Connect the radio to the service
monitor.
D. Receive Audio Adjustment
1. Using service monitor, modulate the
correct RF signal into the receiver with a
1kHz tone at 3kHz deviation. If
bandwidth is 12.5, then modulate at
1.5kHz deviation. (If using private line,
add 0.75kHz private line deviation to the
signal.)
2. Adjust the level at TP10 (2005141
controller card) for 1V
p-p
using the REC
gain adjustment R59 (2005141
controller card front panel).
E . Transmit Deviation Adjustment
1. Simultaneously press buttons 5 & 7
on the 2005141 controller card. This will
cause the controller to transmit for
approximately 8 seconds.
2. Measure the deviation level using
service monitor.
3.
Adjust the TX level (2005141
controller card front panel) for 3kHz
deviation. If the bandwidth is 12.5kHz,
then adjust for 1.5kHz deviation (If using
private line, add 0.75kHz private line
deviation to the signal.)
Note, slightly higher S/N levels can be
obtained by increasing the RF
modulation levels to 4 and 2kHz
depending on the channel spacing. Do
not exceed these deviation levels. All
sites in the system should be set to the
same modulation level.
6.4 600 Ohm Level Adjustment
Procedure for Communications
Note: To use the 600 ohm input for
receive audio, a jumper must be across
pins 2-3 of JP8. JP8 is located internally
on the main controller card.
1. RX Adjustment
a. Ensure Base Station TX level is
adjusted properly. Nominal base
station TX level would be 1V
p-p
or
approximately 0dB.
b. Transmit a tone from the Base
Station.
c. Ensure tone is not clipped by
viewing waveform with an
oscilloscope.
d. Adjust the level at TP10 (2005141
controller card) for 1V
p-p
using the
REC gain adjustment R59 (2005141
controller card front panel).