User's Guide

DANIELS
ELECTRONICS LTD
TM
3-4 CI-PM-3 Paging Modulator Instruction Manual
5. Set SW3 (SET MOD) to 2 LEVEL, and SW4 (SET DEV) to the Data “1” (top) position. For
a VHF system adjust R5 (2-LVL +Dev) for +4.8 kHz deviation (4.8 kHz above center
frequency). For a UHF system adjust R5 for +4.2 kHz deviation.
6. Change SW4 (SET DEV) to the Data “0” (bottom) position. For a VHF system adjust R6
(2-LVL -Dev) for -4.8 kHz deviation (4.8 kHz below center frequency). For a UHF system
adjust R6 for –4.2 kHz deviation.
7. Set shunt jumper JU23-B.
8. Change SW3 (SET MOD) to 4 LEVEL. Adjust R4 (4-LVL -Dev) for -1.6 kHz deviation.
9. Change SW4 (SET DEV) to the Data “1” (top) position. Adjust R3 (4-LVL +Dev) for +1.6
kHz deviation.
10. Set SW3 (SET MOD) to 2 LEVEL. Set SW4 (SET DEV) to the center position. Adjust R23
(BP DEV ADJ) for maximum deviation of +/-4.8 kHz.
3.10 PLL Setup
CI-PM-3 PLL adjustments are factory set. It is strongly recommended that they not be altered.
The following procedure applies only if field adjustment is required:
1. Install Power Enable surface mount jumpers JU37, JU39, JU56 and JU59.
2. Ensure front panel SW1 (FREQ REF) is set to EXT, and shunt jumper JU6-A is removed.
3. Set shunt jumpers JU23-A and JU41-A (or not installed).
4. Connect the 50 Ohm output of a high stability, 10 MHz reference to front panel REF IN SMA
connector J3. Ensure the output level of the external reference is between 0.5 to 2.5 V rms.
Steps 5 through 7 apply to Daniels VR-3/150 transmitters.
5. Measure and record the voltage at TP13 with the DMM.
6. Measure the voltage at TP12 with the DMM.
7. Adjust PLL CAL potentiometer R101 until the voltage measured at TP12 matches the voltage
measured in step (5) above within ± 0.2 Vdc. Note that when the PLL locks in, the voltage at
TP12 will also lock in to within ±0.2 Vdc of the voltage at TP13. At this point further
adjustment of R101 will not change the value unless it is brought out of lock.