ATR833S / P/N 833S-(Cxxx)-(Cxxx)
Operation and Installation
11
Document-Nr.: 01.142.010.71e / Revision:1.03
2.4 Frequency Setting
Frequency setting is always done by in two steps, as follows:
1. entering a new standby frequency to the desired value, and then
2. interchanging the new standby frequency and the previous active
frequency by using the swap button
.
Entering a new standby frequency can be done by
a. manual input,
b. recall of previously stored frequencies from the user memory
(memory locations 1-20), or
c. recall from the list of the last 10 used frequencies.
2.4.1 Automatic Selection 8.33 / 25kHz Channel Bandwidth
Whether a frequency is used with channel width 8.33kHz or 25kHz, is
automatically determined by the value of the frequency entered and
requires no additional user activity.
The numbering scheme that is used for distinction of the two channel
widths is internationally standardized by the ICAO, and consistently used
in official documents (e.g. VFR navigation charts) as well as in the voice
phraseology used in ATC radio communication.
Channels used with 25kHz width are entered in multiples of 25kHz:
123.500, 123.525, 123.550, 123.575, 123.600 etc. These are compatible
with the old 25 kHz-only radios. To use the same frequencies with
8.33 kHz width, the frequency values entered are increased by 5kHz:
123.505, 123.530, 123.555, 123.580, 123.605 etc.
For more detailed information please refer to chapter 5.1
– but
,
as said
above, for correct channel width selection this knowledge is not required.
2.4.2 Manual Frequency Input
The standby frequency is inputted by
selecting with the ► button which part of the frequency to change,
and
changing the selected part with the
FREQ
rotary knob.
The swap button
interchanges the newly set standby frequency and
the former active frequency.
