Squelch Threshold Adjustment - Standard Horizon HX400 Service Manual

Squelch Threshold Adjustment (Wide Band-
width)
1. Press the [p] or [q] key to
select the display to "N TH
W".
2. Press the [SQL] key to enable
adjustment of the Squelch Threshold level.
3. Press the [p] or [q] key to
select a small character of
lower right corner of the dis-
play to "C".
4. Set the RF Signal Generator output level –8
dBμV (with a standard FM modulation: ±3.0
kHz deviation @ 1 kHz) at 156.800 MHz.
5. Press the [H/L] key to read the Squelch Thresh-
old level, then press and hold the [H/L] key for
2 seconds to save the Squelch Threshold level at
the band center.
6. Press the [p] key to change
the "C" character to "H" at
the lower right corner of the
display.
7. Change the RF Signal Generator to 174.000
MHz. The output level keeps –8 dBμV (with a
standard FM modulation: ±3.0 kHz deviation @
1 kHz).
8. Press the [H/L] key to read the Squelch Thresh-
old level, then press and hold the [H/L] key for
2 seconds to save the Squelch Threshold level at
the high band edge.
9. Press the [q ] key twice to
change the "H" character to
"L" at the lower right corner
of the display.
10. Change the RF Signal Generator to 134.000
MHz. The output level keeps –8 dBμV (with a
standard FM modulation: ±3.0 kHz deviation @
1 kHz).
11. Press the [H/L] key to read the Squelch Thresh-
old level, then press and hold the [H/L] key for
2 seconds to save the Squelch Threshold level at
the low band edge.
12. Press the [CLR(WX)] key to exit from this align-
ment item.
Squelch Threshold Adjustment (Narrow Band-
width)
1. Press the [p] or [q] key to
select the display to "N TH
N".
2. Press the [SQL] key to enable
adjustment of the Squelch Threshold level.
3. Press the [p] or [q] key to
select a small character of
lower right corner of the dis-
play to "C".
4. Set the RF Signal Generator output level
–8 dBμV (with a standard FM modulation:
±1.5kHz deviation @ 1 kHz) at 156.800 MHz
5. Press the [H/L] key to read the Squelch Thresh-
old level,then press and hold the [H/L] key for
2 seconds to save the Squelch Threshold level at
the band center.
6. Press the [p] key to change
the "C"character to "H" at
the lower right corner of the
display.
7. Change the RF Signal Generator to174.000
MHz. The output level keeps –8 dBμV (with a
standard FM modulation: ±1.5 kHz deviation @
1 kHz).
8. Press the [H/L] key to read the Squelch Thresh-
old level,then press and hold the [H/L] key for
2 seconds to save the Squelch Threshold level at
the high band edge.
9. Press the [q ] key twice to
change the"H" character to
"L" at the lower right corner
of the display.
10. Change the RF Signal Generator to134.000
MHz. The output level keeps –8 dBμV (with a
standard FM modulation: ±1.5 kHz deviation @
1 kHz).
11. Press and hold the [H/L] key for 2 seconds to
read the Squelch Threshold level at the low
band edge.
12. Press the [CLR(WX)] key to exit from this align-
ment item.
Alignment - 4
Alignment
HX400 Service Manual