Help with Border Patrol Comms

[MB]

I haven't been able to hear any Border Patrol comms in my area for a while now. What used to be voice transmissions are now white noise and squawking sounds.

The frequencies still use CTCSS tones (100.0, 123.0, 151.4, 110.9, 206.6). So this makes me wonder if they are digital or not. I have recieved Close Call hits on my BC246T when I am near B.P. units and the frequency is 162.900 with a CTCSS of 110.9.

Some other frequencies that used to be active near my location (upstate N.Y) are: 163.625, 163.725, 163.775, 165.2375, 163.675.

Sometimes it sounds like white noise and other times I hear what sounds like MDC1200 ANI sounds (squawking) with no voice heard at all. The MDC1200 sometimes repeats over and over for several seconds (squawk, squawk, squawk, squawk. etc. ) Click on the link below to hear what MDC1200 sounds like.

Any ideas on what I am hearing???

http://www.kb9ukd.com/digital/

 

[Mozilla]

Border Patrol

The " white noise you are hearing is encryption( most likely DES, DES-XL).... most of the border systems are still analog but have been using encryption a lot more. The MDC bursts you hear is OTAR ( over the air reprogramming) of the encryption keys to the subscriber units.