190-01182-02
GTR 225/GNC 255 TSO Installation Manual
Rev. F
Page 6-12
Table 6-11 COM RX Squelch Selections
[1] Software version 2.10 or later.
Table 6-12 COM RX Squelch Settings
[1] The COM RX squelch range (0-100) is a non-linear response.
[2] Many typical installations have the auto squelch set to close at approximately -101 dBm.
6.4.3.3
COM Information Page
The COM INFORMATION page shows the COM board software version, software part number, hardware
version, boot version, boot P/N, FPGA version, and FPGA P/N.
Figure 6-17 COM Information Page
Selection
Description
BASIC
The COM RX SQUELCH value is applied to all frequencies.
ADVANCED [1]
The COM RX SQUELCH values can be set for low, mid, and high
frequencies. The COM RX SQUELCH value is linearly interpolated for
frequencies between the low (118.000 MHz), mid (127.000 MHz), and high
(136.975 MHz or 136.990 MHz for 25kHz and 8.33 kHz spacing,
respectively) frequency values.
SPACING
The COM RX squelch values are adjusted separately for 25 kHz and
8.33 kHz spacing.
SQUELCH (BASIC)
LOW, MID, HIGH
(ADVANCED)
The COM RX squelch is adjustable in the range of 0 to 100. The default
value is zero. Decreasing the value will allow the squelch to be broken with
low signal levels. Increasing the value will require higher signal levels to
break squelch.
COM RX Squelch Setting
[1]
Original
Calibration
Approximation
Expanded Calibration
Approximation
0 [2]
Auto Squelch Open
-99 dBm
-105 dBm
Auto Squelch Close
-101 dBm
-107 dBm
75 [2]
Auto Squelch Open
-97 dBm
-99 dBm
Auto Squelch Close
-99 dBm
-101 dBm
100
Auto Squelch Open
-93 dBm
-93 dBm
Auto Squelch Close
-95 dBm
-95 dBm
