Ltr

[RADIOGUY2002]

Is their a way to encrypt radio talkgroups on a system. Whats the difference between a systems that decidates a user to a speicffic repeater on an ltr instead of having mutiple users roam on serveral repeaters.

Do ran codes effect LTR?

[wayne_h]

Originally Posted by RADIOGUY2002

Is their a way to encrypt radio talkgroups on a system.

As long as the audio can fit within the normal vocal range passed by the radio equipment. All I can think of for th emost secure is some rolling-code speech inversion. You aren't going to get any true encryption to pass through an LTR system.

Whats the difference between a systems that decidates a user to a speicffic repeater on an ltr instead of having mutiple users roam on serveral repeaters.

Do ran codes effect LTR?

I'm not sure what you mean for either one of these questions. I've never heard of a "ran" code.

[RADIOGUY2002]

First part of the question second from above

Apperntily their are different ways to setup LTR systems. One way is to deciate a talkgroup ot talkgroups(user) to a one channel only type deal insted of having mutiple talkgroups that roam amongest the repeaters. It allows this user to have free up time to commit to them only. Instead of mutiple users. Ran code is for digital version of pl / dpl concept. I was not sure if that plays into ltr at all.

[fineshot1]

Originally Posted by RADIOGUY2002

First part of the question second from above

Apperntily their are different ways to setup LTR systems. One way is to deciate a talkgroup ot talkgroups(user) to a one channel only type deal insted of having mutiple talkgroups that roam amongest the repeaters. It allows this user to have free up time to commit to them only. Instead of mutiple users. Ran code is for digital version of pl / dpl concept. I was not sure if that plays into ltr at all.

I think you are referring to IDAS (Icom Digital Advanced System). You can not run LTR on IDAS.
Its either going to be one or the other. If you want to set up LTR it will be in the analog mode.
RAN(Radio Access Number) codes are the equivalent of the Motorola NAC but are only used
when the system is configured for IDAS. At least that's my understanding of basic IDAS.

If I got something wrong please someone correct me.

[RADIOGUY2002]

Okay, thats what I thought.

[fwradio]

Icom is working on trunking for IDAS. They decscribe it as a basic trunking, very similar to LTR. They say it will not be compatible with the more advanced trunking that Kenwood has brought out.

[RADIOGUY2002]

See here for reference
http://www.mygmrs.com/nxdn/index.php

Kenwood Verison is know as Nexedge

Yea, but that really was not part of my question. Come to find out that Icom need to setup by zone with all system frequencies in it.

IE 01 461.0500
02 462.0500
03 463.0500

Talkgroup
0-01-045 being the home channel of one

and

0-03-250 being the home channel of three

So, it needs to be done like this zone 1, ltr, home channel 461.0500, channel's 045 and
zone 2, ltr, home channel 463.0500, channel's 250

However, its not the case for this other system. Its setup different some how, technology etc.

[Ray_Air]

[QUOTE=RADIOGUY2002;843945]Is their a way to encrypt radio talkgroups on a system. Whats the difference between a systems that decidates a user to a speicffic repeater on an ltr instead of having mutiple users roam on serveral repeaters.

Do ran codes effect LTR?[/QUOTE

Yes, you can encrypt on LTR systems. Whatever T.G's you want encrypted you will need to install encryption boards in those radios. Most boards are highly configurable and pricey. You will need to set delay times for the voice privacy module because you will be using a system where a repeater is used. You don't want to miss sync bursts or synchronization signaling. Don't waste your money with voice inversion or slow hopping code scramblers as they offer very minimal security.
Here's some prices:
(per board):
Transcrypt 430 (general security applications) $400
Transcrypt 460 (medium security) $550
Transcrypt DES (higher security) $699
Transcrypt AES (highest security) $699
Motorola DES or AES is probably about a grand.

[wayne_h]

Originally Posted by Ray_Air

Yes, you can encrypt on LTR systems.
<snip>
Don't waste your money with voice inversion or slow hopping code scramblers as they offer very minimal security.

So how do you recommend to him he get past the audio filtering of the repeaters which would normally make encryption unusable?

[RADIOGUY2002]

I now you can encrypt a talkgroup, I understand that.

But,, like motorola systems they have conect tone's . Is their somthing like that on ltr systems?

[Ray_Air]

Originally Posted by wayne_h

So how do you recommend to him he get past the audio filtering of the repeaters which would normally make encryption unusable?

I don't know his LTR systems specs. The repeaters in the LTR system would have to accept the encrypted audio. I know with rolling code the scrambler can be modified to delay the initial sync an extra couple hundred milliseconds so the repeater will transmit the full initial sync . Most digital encryption that I have used have continuous sync. I am sure a a slight repeater mod will pass digital encryption. The encryption wouldn't effect the sub-audible data for LTR trunking.