Sequence Of Adjustments; Item 1: Vctcxo - Ericsson EF738 Service Manual

Service Instructions

Sequence of Adjustments

Item 1: VCTCXO

Purpose:
Checking and, if necessary, calibrating the reference frequency generator for the
synthesizers
Test method:
Radio test set in TX mode, measured with a frequency counter
Input signal:
None
Measurement point:
Transmitter frequency at antenna connector
Limit:
890.0125MHz ±200Hz
Procedure:
1. Turn on the transmitter (TP-2:2)
2. Disable the AFC (TP-15:0)
3. Check the frequency error
4. If the transmitter frequency is not within 890.0125MHz ±200Hz;
enter VCTCXO calibration (TP-18:)
5. Press M + # to enable the calibration
6. Use # and * buttons to change value and press M + S to store the new value
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