3 rssi system level tuning – Motorola PR400 User Manual

Page 48

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August, 2004

6881096C24-A

5-14

Radio Alignment Procedures: Receiver Tuning

3.

Set softpot to its maximum value to mute the radio.

4.

Adjust the softpot value by using the slider, keying in the edit box or using the spin controls. Press
ENTER to confirm the selection or use the spin controls. Do this until the radio is totally unmuted.
Verify the squelch closing by inputting a signal level of 4 dB lower than that of the 10 dB SINAD
level.

5.

Repeat Steps 2 through 4 of Manual Squelch Tuning, for frequency points F2-F7.

6.

Press Program to commit the softpot values into the radio.

7.

Exit the Squelch Tuning function.

5.5.2.2 Auto Tune

When you press the Auto Tune button, the radio automatically returns an optimum squelch value.

After you press the button, the radio may need time to produce an optimal setting for the squelch
attenuation. The following steps describe the auto tune process:

1.

Select current frequency point (F1 being the first), then press Auto Tune.

2.

Repeat Steps 3-4 of the Manual Squelch Tuning section for frequency points F2-F7.

5.5.3

RSSI System Level Tuning

1.

Under the Rx Align menu, select RSSI Tuning (

Figure 5-11

).

2.

Inject an on channel signal to the radio at -47 dBm at the frequency listed. Modulate the signal
with a 1 kHz tone at 60% deviation (3 kHz) to verify that the radio is receiving the desired fre-
quency. RSSI tuning is only done at 25 kHz channel spacing.

3.

Change the level to the defined dBm level in the softpot box. (-115 dBm or -105 dBm).

4.

Press the Update button for the softspot to be tuned to the RSSI value correlating to the applied
level. The programmed RSSI value will be displayed.

Note: Proceed with caution since this procedure automatically programs the softpot value

into your radio.

Note: Auto Tune will automatically update your radio’s codeplug. Please be careful when

using it.

Figure 5-11. RSSI Tuning

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