Dataradio Paragon, Техническое руководство

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120 20170-204a Paragon
PD
Technical Manual
50
6.4.3 Exciter Module (T881,T857 or T837)
Note 1: Refer to (T881), Figure 32 (T857) and to Figure 36 (T837) for locating tuning controls and com-
ponents.
Note 2: When the synthesizer is unlocked, the front panel green LED called "Supply" will flash indicat-
ing that it needs re-tuning.
Warning: The LED will also flash when the unit is in setup mode while connected to the
PGM800win program.
6.4.3.1 Initial Setup
1. Shut down power to the base station.
2. Prepare the multimeter to DC Volts.
3. Remove the exciter (T881, T857 or T837) module from the base station rack frame.
4. Remove the exciter top cover (nearest the handle).
5. Connect a 3 feet long double shielded cable (N-M to BNC-M) between the IFR T/R output and
the exciter antenna connector.
6. Connect the Paragon
PD
Extender Rail Kit to the empty chassis exciter slot.
7. Apply power to the base station.
6.4.3.2 Synthesizer Alignment
Single channel: Connect the multimeter to either side of L309 (T881) or the long lead of L1 in the VCO
(T857 and T835) (this measures the synthesizer loop voltage).
1. T881 (800/900 MHz) Tune VCO trimmer CV300 for a synthesizer loop voltage of 10V DC.
2. T857 (UHF) Tune VCO trimmer C6 for a synthesizer loop voltage of 10V DC.
3. T837 (VHF). Tune VCO trimmer CV1 for a synthesizer loop voltage of 9VDC.
Multiple channels (adjusting as shown for single channel above):
1. T881 (800/900 MHz) Adjust the VCO loop to 10V using the middle frequency channel.
2. T857 (UHF) Adjust the VCO loop to 10V using the middle frequency channel.
3. T837 (VHF) Adjust the VCO loop to 9V using the middle frequency channel.
All channels should lie within the upper and lower limits of 16V and 3V respectively for the
T881 and T857 or within 13V and 5V for the T837.
Note:
Normally, the fast TX key option is installed and the synthesizer is always energized. In
the case where that option was not fitted, key the transmitter by pressing the front panel
Carrier button to make the above adjustment possible.
6.4.3.3 TX Frequency Error Adjustment
1. Apply the following settings to the IFR:
-
Receiver mode
- IFR RX frequency to match the main radio TX frequency
- IF Filter set to 30KHz