Mobiext 1200 network

[fe8769]

From months now I have every day some Mobitex 1200 transmission on :

30 MHz, 31.575 MHz 32.325 MHz 34.3 MHz

Where are these frequencies from ?

Wcode decodes some frames

[R4002]

I believe these are ionospheric sounders, also sometimes called "chirpers".  There are several that operate on 30.000 MHz or very close to 30.0000 MHz.  Same with 32.325 MHz and 31.575 MHz.  It is believed they are operating somewhere out of the Middle East, but this is unconfirmed.