Hytera MD652, Руководство по обслуживанию

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VHF1 (136
‐
174 MHz)
Tuning Description
43
Items Method
value in the dialog box on Tuner until the frequency deviation is 5k±20 Hz .
11. Press the Enter key on the keyboard to confirm your settings.
12. Click the “Transmit Off” button.
RX Section
Front-end Filter
1. Connect the antenna connector of the radio to HP8921.
2. Connect the Audio Out port of the radio to the Audio In port of HP8921,
and set HP8921 to RX test mode.
3. Set the HP8921 parameters as follows:
Output RF signal: -118 dBm/Frequency
Modulation frequency: 1 kHz
Modulation deviation: 3 kHz
De-Emphasis: 750 us
4. Observe the value displayed on the HP8921 and adjust the vernier until
the SINAD value is more than 14 dB .
5. Set the HP8921 parameters as follows:
Output RF signal: -25 Bm/(Fr22.425 MHz)
6. Observe the value displayed on the HP8921 and adjust the vernier on the
Tuner until the SINAD value is less than 14 dB .
7. Press the Enter key on the keyboard to confirm your settings.
Front-end Gain
8. Connect the antenna connector of the radio to HP8921, and set HP8921 to
RX test mode.
9. Set the HP8921 to output -70 dBm/Frequency unmodulated RF signal.
10. Press the
Enter
key on the keyboard to confirm your settings.
Receive Oscillator
Voltage
11. Connect the antenna connector of the radio to HP8921, and set HP8921 to
RX test mode.
12. Open the Tuner software, go to “TUNE_DATA -> RX -> Receive Oscillator
Voltage” in the navigation tree on the left.
13. Click the “Save” button to save the existing value to the radio.