AValon RF DX404 - Manual (Page 17)

AVALON RF, INC. Page 14 of 28
DX404/DX504/DX604 User’s Guide & Operating Manual
3.3 Setup.
3.3.1 Tuning the audio sub-carrier frequencies (DX504/DX604 only).
The Audio1 sub-carrier frequency is factory preset to 6 MHz.
The Audio2 sub-carrier frequency is factory preset to 6.5MHz.
The audio sub-carrier frequencies can be tuned anywhere between
5MHz to 7MHz in increments of 10KHz.
Audio1: *21#
Audio2: *22#
Where is from 500 to 700 (the first digit represents
megahertz & the last digit represents 10’s of kilohertz), tunes the
audio sub-carrier to the desired frequency. If the ‘#’ character and
are omitted, the sub-carriers will tune to the factory preset.
E.G.:
*21# 665 tunes Audio1 to 6.65 MHz.
*22# 700 tunes Audio2 to 7MHz
*22 tunes Audio2 back to 6.5MHz
3.3.2 Setting the audio sub-carrier bandwidth.
The audio IF bandwidth can be set to narrow for 75 KHz deviation
or wide for 125 KHz deviation.
Audio1: *211 sets Audio1 bandwidth to Narrow.
*210 sets Audio1 bandwidth to Wide.
Audio2: *221 sets Audio2 bandwidth to Narrow.
*220 sets Audio2 bandwidth to Wide.
Selecting an incorrect audio bandwidth results in a low and distorted
audio output.