ATR833-II / P/N 833-II (Cxxx)-(Cxxx)
Operation and Installation
17
Doc.-No. 01.143.010.71e / Revision 1.01
2.5.2 SQL – Squelch (noise barrier)
By shortly pressing the SET key once, with the help of the rotary knob
the squelch level can be adjusted. (Note: This is not related in any way to
the intercom functionality.)
This is a threshold that has to be exceeded by radio signal levels from
other transmitters, in order to activate the reception circuitry. The higher
the number, the stronger the radio signals have to be in order to be
received.
ACT
123.450
SBY
118.275
SQ 2
Range: 0 - 9
The setting for the squelch depends on different factors. For motor
aircrafts an initial higher setting is typically appropriate, gliders may use a
lower value. A lower number means higher input sensitivity.
This allows reception of weaker signals (radio stations at higher
distance), but can also result in pickup of own-aircraft radio interference
sources (engine, strobe lights).
2.5.3 VOX –Voice Activated Intercom
By shortly pressing the SET key twice, with the help of the rotary knob,
the threshold volume VOX for intercom voice detection can be adjusted.
(Note: This is not related in any way to radio reception or squelch.)
VOX defines the crew’s speech volume that is required to activate the
intercom functionality. The higher the value, the louder you need to
speak in order to activate the intercom.
Exception: VOX 0 corresponds to “always on”
The default squelch setting is 05. At higher values weak
signals could be suppressed.
