Hytera MD78X, Руководство по обслуживанию, Страница: 270 / 519

Tuning Description
UHF3 (350
–
400 MHz)
52
Items Method
2. Set HP8921 to output an unmodulated RF signal with a value of “-70
dBm/Frequency (current channel frequency)”.
3. Press the Enter key on the keyboard to confirm your settings.
4. Click the “Save” button on Tuner to save the existing value to the radio.
Receive Oscillator
Voltage
1. Connect the radio to HP8921 via the antenna connector, and set HP8921
to RX test mode.
2. Open the Tuner software and go to “TUNE_DATA -> RX -> Receive
Oscillator Voltage” in the left navigation tree.
3. Set HP8921 to output an unmodulated RF signal with a value of “-47
dBm/Frequency (current channel frequency)”.
4. Click the “Save” button to save the existing value to the radio.
8.2.2
Testing the Radio
After tuning all the items of the radio, you need to test the digital RF signal of the mobile radio via
Aeroflex 3920 (Digital Radio Test set).
Transmitting
Step 1
Connect the mobile radio to Aeroflex 3920 via the antenna connector.
Step 2 Open the Tuner software and go to “TEST -> TX -> Transmit BER (0.153)”.
Step 3
Select the channel to be tested and select the corresponding power level (High Power or Low
Power) in “Parameter” on Tuner.
Step 4 Click the “Transmit On” button on Tuner.
Step 5
Set the parameters on the Aeroflex 3920 as follows:

Frq: Be consistent with the TX frequency of the channel to be tested.

STD IB 511: .153
Step 6
Observe the “avg” value of “UUT TX Bit Err” parameter in “UUT Measurements” module of
Aeroflex 3920, which is the average bit error rate of the tested channel during transmitting.
The radio is operating properly when the Aeroflex 3920 parameters are as follows:

FSK Error:
≤
5%

Symbol Clock Err:
≤
100 Hz

Signal Power: 3.9
–
4.5W

Magnitude Error
: ≤
1%