SELCAL Decoder

General description

The SELCAL supports aero selective call (ICAO, Annex 10). It needs, that the receiver has been set to the correct frequency. The frequency error should be less than 10 Hz to provide correct decoding. The SELCAL consists of 2x2 tones (duration 1 sec), according to the following specification:

Designation Frequency (Hz) 
A     312.6
B     346.7 
C     384.6
D     426.6
E     473.2
F     524.8
G    582.1
H    645.7
J     716.1
K   794.3
L    881.0
M    977.2
P    1083.9
Q   1202.3 
R    1333.5 
S    1479.1 

Configuration

The SELCAL decoder doesn’t need any configuration.

FFT

The FFT button opens and closes the power spectrum window. You can for example close the power spectrum window when the decoder has locked into correct frequency in order to get more space for text window

Save

The save button opens the log file control Dialog, which is used to open or close a log file. The detector text window can be also saved into file or sent into socket.

Lock

This button has no effect in SELCAL decoder.

Reset

The reset button resets the decoder and clears the text window.