Rev A
Installation
2—5
2.3.1
Modulation Compensator
The Modulation trim-potentiometer, (see Section 2–6, Modulation Compensator
Settings), compensates for slight variations in deviation sensitivity with frequency.
Set the trim-pot dial according to the following graph:
These compensator settings are approximate. Each mark on the potentiometer
represents about 1.8% modulation compensation. For more exact settings, see
Section 5.2.2, Composite Output.
Replace the top cover before operating the transmitter.
2.3.2
RF Tuning Adjustments
All the RF stages are broadband to cover the 88 to 108 MHz broadcast band. The RF
amplifier stages require no tuning.
Note:
If you requested it, the FSK chip on the RF Exciter Board has been
pre-programmed for your operating frequency. This chip is
replaceable. Should you need to change the location of your
translator, contact Crown Broadcast for a replacement chip with your
new FSK ID. To disable auto ID, remove the jumper from the auto ID
location on header HD2 on the RF Exciter Board.
Illustration 2–6 Modulation Compensator Settings
FREQUENCY
(MHz)
85
Mod.
(%)
0
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100 101 102 103 104 105 106 107 108 109 110
5
10
15
20
25
30
35
40
45
50
55
60
Mod.
(%)
0
5
10
15
20
25
30
35
40
45
50
55
60
