User manual

Table Of Contents

5-14 Section 5: Module Configuration

Moseley SL9003Q 602-12016 Revision G

5.6.2. Changing Frequency — RX

The carrier frequency of receiver may be changed via the front panel within a 20 MHz

range without internal adjustment or realignment.

This is accomplished as follows:

1. Power-up the unit and navigate the LCD screens as follows and press enter:

CONFIGURE

QAM Radio Launch

Freq

QAM RADIO RX Config

MHz944.5000

2. Using the cursors, change to the desired frequency. Press ENTER. The unit

should continue to indicate AFC LOCK (green) on the front-panel.

3. The receiver synthesizer AFC voltage will change depending on the frequency

programmed from the front panel. This voltage will typically be between 1.0 Vdc

to 2.4 Vdc for the 944 MHz to 952 MHz band. Navigate the LCD screens to

monitor the AFC voltage as follows:

STATUS

QAM Radio Launch

VDCAFC

SYNTH LOCK

4.5

100

Note: Earlier generations of the SL9003Q required an internal adjustment on the

Receiver Module to center the AFC voltage. These units can be identified when

changing the frequency by 5 MHz will cause the RX AFC to loose lock. With these units

the Receiver Module was placed on an extender card and to access the RX AFC

adjustment. Depending on the “direction” that the frequency was moved, the voltage

might read either 0.00 or 9.99 VDC. While monitoring this voltage, the user would adjust

the RX AFC on the Receive Module (using a very small flat blade screwdriver) until the

voltage read 4.5 +/- .25 VDC.