User's Guide

DANIELS
ELECTRONICS LTD
TM
CI-PM-3 Paging Modulator Instruction Manual 3-5
Steps 8 and 9 apply to Daniels UHF transmitters.
8. Monitor TP12 with an oscilloscope.
9. Adjust the PLL CAL potentiometer R101 until the voltage measured at TP12 is over 2.7 volts.
You should observe a clean DC voltage when the PLL locks in. Any voltage below 2.7 volts
results in a badly distorted 10 MHz square wave.
10. Replace shunt jumper JU6-A.
3.11 Data Delay Setup
1. Enable the DATA DELAY option by installing Power Enable surface-mount jumpers JU38
And moving the two DATA DELAY shunt jumpers of JU36 to the DELAY (vertical) position.
2. Set front panel switches SW2 (MODE) to SETUP, SW3 (SET MOD) to 2 LEVEL, and SW4
(SET DEV) to “Continuous Bit Stream” (refer to SW4 DETAIL in Figure 6-1).
To calibrate the positive and negative edge delay:
3. Set the oscilloscope for 1.0 V/Div (vertical) and 0.5 µs/Div (horizontal). Select channel 1 as
trigger input and set Trigger Slope to positive.
4. Monitor the data signal at TP9 on channel 1 of the oscilloscope.
5. Monitor and record the period of the data delay pulse at TP7 on channel 2 of the oscilloscope.
6. Set Trigger Slope to negative.
7. Continue monitoring the data signal at TP9 on channel 1 of the oscilloscope while monitoring
the period of the data delay pulse at TP7 on channel 2.
8. Adjust R95, DELAY SYNC, until the period of the data delay pulse measured at TP7 is
identical to that measured in step (5) above.
To set the delay resolution (output frequency of Programmable Counter U22):
9. With surface mount jumpers JU31A, JU32A and JU33A installed, monitor the frequency of the
signal at TP8.
10. Adjust tuning capacitor C55 for a frequency of 1.0 MHz (+/- 10 Hz) at TP8.