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Old 08-27-2010, 3:54 PM
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Default speech inversion on 157.1750 marine VHF channel 83

i just heard what sounded like some kind of speech inversion scrambling on ch 83. it was defiantly some kind of scrambling i also believe this is a USCG assigned channel for my area but i think its really odd that its in use because USCG has moved to rescue 21 in my area
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Old 08-27-2010, 4:24 PM
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Happens all the time, Gypsy Fishermen use what-ever channel they want, and the encryption makes it harder to track down who they are, but now with Rescue 21 and maybe they are running AIS, the CG can narrow down who the suspects are.


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Originally Posted by jchjr1114 View Post
i just heard what sounded like some kind of speech inversion scrambling on ch 83. it was defiantly some kind of scrambling i also believe this is a USCG assigned channel for my area but i think its really odd that its in use because USCG has moved to rescue 21 in my area
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Old 08-27-2010, 9:03 PM
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It could be the users selected that channel before they made a dsc - scrambled call. On the Ross DSC 500 radios (per the manual and actual use) you first select a "working" channel then call the other party you want to talk to in scrambled mode, the radios set up the scramblers and move to the working channel from signalling sent over the DSC channel (channel 70). I dont know if other radios work this way also but it is one possibility.
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Old 08-30-2010, 6:13 AM
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Quote:
Originally Posted by jchjr1114 View Post
i just heard what sounded like some kind of speech inversion scrambling on ch 83. it was defiantly some kind of scrambling i also believe this is a USCG assigned channel for my area but i think its really odd that its in use because USCG has moved to rescue 21 in my area

Voice inversion is not "exactly" secure. = Amazon.com: Ramsey SS70C Speech Scrambler Descrambler Kit: Electronics


Voice Inversion Descramblers are everywhere..and Voice Inversion is not the best. Why Vertex thinks it is
so great is beyond me.

With AES, or even DES..You would think even some police municipalities, who still use voice inversion would just upgrade.

You..in my experience, have " Hard Core " scanner listeneners and hobbiest everywhere. Descramblers use to be an item in my youth when my local L/E agency was still low band.

I guess you have ignorant radio folks everywhere huh.....Or people who belive the movies all the time.


FF-Medic !!!!

Last edited by ff-medic; 08-30-2010 at 6:14 AM.. Reason: spelling
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