120 20191-001
Paragon-III
Technical Manual
27
5.2.2.5 RSSI Adjustment
-
Caution: mis-adjusting RSSI may reduce the Paragon-III's Parallel Decode (PD) performance.
-
BDLC-III must be connected to the radio chassis assembly during this process.
1.
T885-xx-0200 (700MHz) receivers:
-
Refer to Figure 20 - T885-0200 Receiver Tuning Controls location
-
Apply an on-channel signal from the RF generator at a level of -110 dBm modulated by a 1 kHz tone at
a deviation of ±6kHz.
-
Adjust RV 345 (RSSI level) for T885 to give 2.0V RSSI output at SK330 pin 2 or on backplane J1
(RX1) or J5 (RX2) pin 5 when measured with a voltmeter (See Figure 13 - 280 03425-001 Radio back-
plane for test point location).
The following RSSI graphics are given as general information only.
Refer to factory technical support
only
if RX data performance degradation is noticed combined with
something that does not look like those RSSI curves.
Figure 19 - T885, Typical RSSI Curve: volt to dBm
5.2.3 Exciter Module (T881-xx-0200)
Note 1: Refer to Figure 21 (T881).
Note 2: When the synthesizer is unlocked, the front panel green LED called "Supply" will flash indi-
cating that it needs re-tuning.
Warning:
The LED will also flash when the unit is in setup mode while connected to the PGM800win program.
5.2.3.1 Initial
Setup
1.
Shut down power to the base station.
2.
Prepare the Multimeter to DC Volts.
3.
Remove the exciter (T881) module from the base station rack frame.
4.
Remove the exciter top cover (nearest the handle).
0
1
2
3
4
5
6
7
-120 -110 -100 -90 -80 -70
dBm
Voltage
