Digital/analog encrypted radios question

TheGerman

Oberleutnant
Belligerents
Jan 25, 2010
5,860
7,597
219
Out West
Ok, talk to me like I'm a complete moron.

I was talking to a few dealers about land mobile radios and everyone seems to want to suggest going digital for the sound quality and encryption.

Seeing as how every manufacturer has their own proprietary stuff when it comes to everything from plugs, to their digital 'trunking' (if Im explaining this right, example would be Kenwood has the NEXEDGE 'system') and excryption, I haven't been able to figure out something:

- Let's say you and your friends have the encryption enabled, and all have the same brand/type of radio. If you disable encryption, can you transmit/receive anything broadcast within your radios' distance from anyone that has a different brand/type (analog/digital) radio on that frequency? From my understanding I was being told that if I had a digital ICOM unit, basically only the other people with digital ICOM units could hear/transmit to me and anyone else would just hear random noises because it doesn't have the same trunking 'system' (If im explaining that right). I can't see how this is a smart thing if true.

- Is this for digital only, and analog doesnt have this 'issue'? Or am I totally misunderstanding this?
 

Alpine 338

Lumberjack
Belligerents
Jun 26, 2010
1,279
261
189
NW Colorado
Analog, aka FM is not compatible with Digital, even though they may still use FM modulation. Then there are different digital modes and modulations like Digital Narrowband, FSK, PSK, ANDVT, etc. Most public service radios use a standard digital modulation type (P25), that is an industry standard, and compatible between manufacturers. And then there are digital radios that use modulation/encryption systems that are not compatible with other manufacturers.

Generally speaking, radios that use analog modulation systems i.e. AM, FM, NFM, etc, are all compatible with each other.
 
Last edited:

TheGerman

Oberleutnant
Belligerents
Jan 25, 2010
5,860
7,597
219
Out West
So from that PDF, I got a few things. Check to see if I got this right.

- With background noise, analog degrades much more slowly while digital will become useless
- Digital works better with weaker signals than analog does
- You basically need to be in the same modulation type to TX/RX each other on digital

So from a scenario of me being out there with a digital radio using IDAS or P25, and someone on their Baofeng is asking for help on a frequency I'm on wouldn't even be heard on my radio, nor could I talk to them, regardless if my encryption is on or off.

How do radios that use analog/digital conventional mixed mode operation fit into this? Still the same because it uses the IDAS or P25 trunking?
 

TheGerman

Oberleutnant
Belligerents
Jan 25, 2010
5,860
7,597
219
Out West
What end game are you after?
As far as what exactly? Not sure I understand your question, but Ill give an answer and see if that helps.

For a business venture, I need 6x squad level comms that need to be encrypted. All units will be attached to a PTT and Peltor headset/mic units. They need to stand up to being beat up a bit, as well as be sand/water resistant and not be drowned out by constant engine and/or gunfire noise. We will add more units as needed.

These will also double as a setup for personal (non HAM/non repeater) use. I've already spoken to a place that I can be licensed for this in the 136-174mhz range so everything is above board since its for business use.

Additionally, I was looking for a vehicle mounted land mobile transceiver for non-squad comms that can hit one of our other vehicles as well as a 'base station' as the areas we are in have shit cell service at best, but LOS would not be an issue.

For handhelds, we were looking at the ICOM F1000D and 3261.

My concern was that if we went with anything that was utilizing the digital trunking in whatever flavor, we'd be able to communicate amongst ourselves but would basically be in the dark/painted in a corner with being able to communicate with anyone who didn't have the same digital trunking 'system'; an example would be what I mentioned above in relation to someone else being by us asking for help on a regular random radio on a frequency we were on, but we wouldn't hear it nor be able to communicate with them.
 

Gunfighter14e2

Rusty Nail
Belligerents
Jul 9, 2002
5,873
6,795
219
Alabama
eHam.net
Good luck finding what your looking for.
FYI A std Ham radio will do everything you need, once to apply out of the box logic. We have never needed anything but a std radio. Plus if it all goes to shit an you can't repair/find what you have, SOL, comes to mind. Keep it simple an apply your own codes like this one I posted in another Ham thread.

"Tell me what the following really means.

Me,...Hello, is Don there?

Her,...No, he just left 20 minutes ago to get his meds filled, an the transmission in his truck serviced. Is that you Al?

Me,...No this is Ralph he was supposed to be over this AM but he never showed an I thought something was wrong?

Her,...He most likely forgot, I'll remind him when it gets back later, you going to be near the phone?

Me,...No going to the track for some testing to see if the new engine is ready for Friday night.

Her,...The 3/8 mile dirt track in Warrior or the 1/2 mile short track near Cullman?

Me,...Neither the 1/4 mile dirt in Attala, should be on the track at 1930 hrs.

Her,...OK I'll tell him.

Me,... OK good, tell him to get there early if he's coming, by. "


No one to date either here, or other places, has broken it yet an I doubt it will ever be as most can not believe something might be embedded into a conversation, that means nothing to them, but everything to others,..
Equipment will never trump, tactics.
 
  • Like
Reactions: Ravenworks

Alpine 338

Lumberjack
Belligerents
Jun 26, 2010
1,279
261
189
NW Colorado
So from that PDF, I got a few things. Check to see if I got this right.

- With background noise, analog degrades much more slowly while digital will become useless
- Digital works better with weaker signals than analog does
- You basically need to be in the same modulation type to TX/RX each other on digital

So from a scenario of me being out there with a digital radio using IDAS or P25, and someone on their Baofeng is asking for help on a frequency I'm on wouldn't even be heard on my radio, nor could I talk to them, regardless if my encryption is on or off.

How do radios that use analog/digital conventional mixed mode operation fit into this? Still the same because it uses the IDAS or P25 trunking?
You are correct, except digital does not work better with weaker signals than analog, generally speaking. However there are some digital modes of operations, and modulation types like FSK, and PSK that can successfully operate at the noise floor, or well below it. They can be encrypted, and/or use frequency-hopping, which not only makes it hard to intercept and gain intelligence from, but also very difficult to jam.
I can't speak for every brand or model of radio equipment out there, but in this day in age, things are no longer as simple as just buying a radio, turning it on, and talking with others.
At one time, I had to install and program two-way radios that operated in the VHF Govt band. As the article mentioned, we were forced to go Narrowband, and Digital. The radios we used were Motorola Spectra, and we not only had to program (via computer) the operating frequencies, but also modes of operation, like P25, simplex calling channels, repeater coding, and even private channels (aka tactical channels). We didn't use a trunking system, but our system allowed for it to be set-up and used. We also programmed some analog channels in our radios, such as 2-meter channels, WX channels, etc. If the radios have the capability, you have the software, time, and know-how, the sky is the limit. However, none of it can be done on the fly in the field.
Since you mentioned trunking systems, that's another large problem in addition to going digital. Just ask anyone in Los Angeles County (Govt), and how many issues they have that they can't get Motorola to fix.
That is why BLM and USFS Fire Fighters where allowed to stay analog, and not forced to move to Digital Narrowband because of all the issues with Digital Narrowband has in the mountains.
 

magtech

Ole one eye
Belligerents
Feb 22, 2013
154
70
34
The posted PDF really doesn't talk about encryption for security sake. It merely talks about standards. Encryption can be done digitally, through secure key encryption (same as internet and computers). RF transmissions can be seen as a slower version of WIFI ( digitally). Look into how information is encrypted in that wireless standard. Combine that with frequency hopping and other techniques then you start getting layers of encryption. On top of that you can encrypt what you say within the message itself, like Gunfighter did.

If you are trying to break mil/civil service encryption you'll have to delve into gov standards and find someone with working knowledge to do so. Doing so online will probably get you in jail.. EVERYTHING you do in the COM world is tracked. Its up to you how you work with that.