Oricom DTX4200 Operating Instructions Manual page 25

The VSWR and Power test can vary depending on installation
conditions. If TPI feature is turned off in the settings menu, the TPI
indicator will show 5 bars during TX.
If an incorrect or no antenna is connected and power output is less than
3.5W, "ANT-X" will be displayed when TPI feature is turned on or off.
When "ANT-X" is displayed, the radio has enabled protection mode and
reduced RF output.
Treble
Allows adjustment of the level of higher audio frequencies of the radio
speaker in 8 steps, use channel selector to select desired level.
Correct Antenna install with 5W
VSWR 1.2 with 4.5W
VSWR 2.6 with 4W
VSWR 3.5 with 3.5W
VSWR 4.4 with 3W
< 3W
Operations
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