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Part 4: Transmitter RF Levels and checks
This section shows the typical RF levels expected throughout the transmitter path
and the expected control voltages for both the UHF and IF synthesisers. A block
diagram showing the locations of the RF measurement points is shown in figure
4.1.
Part 4.1 : Transmitter Testing Set-up
To check the transmitter the following conditions have to be set:-
1. Set the d.c. power supply to 3.8volts.
2. Using the GSM/PCN test jig power up the hhp and via the keypad enter the
following menu options to put the hhp into receive mode:-
•
Press "B"- (TX Options).
"Suspend Mode
Function Id"
This message indicates that the hhp has entered engineering test mode.
•
Press "A or B"
according to which tx frequency band is required.
Option A = GSM900
Ones and Power Level: 5)
Option B = GSM1800
Ones and Power Level: 0 )
The HHP is now set to Normal transmit burst on channel 62 or 699 on power
level 5 or 0 respectively.
• The Transmitter parameters can be altered by another sub menu, these
being:-
A. Change Channel
B. Change power level
C. Set modulation type ( 0's, 1's or random)
Once this key is pressed the hhp should display:-
(ARFCN:62, Transmit burst type:Normal, Modulation:
(ARFCN:699, Transmit burst type: Normal, Modulation:
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