DOES SDS 200 MUTE ENCRYPTED TRANSMISSIONS?

Status
Not open for further replies.

cagosti

Newbie
Joined
Feb 1, 2008
Messages
7
Before I buy one
there is a lot of DES-OFB encryption in my area and most P25 scanners
receive encrypted transmissions and give you "gerbil talk"

I want the scanner to ignore/MUTE encrypted P25 transmissions can the SDS-200 do that ?

Thanks
Charles
 

n1chu

Member
Premium Subscriber
Joined
Oct 18, 2002
Messages
2,865
Location
Farmington, Connecticut
Before I buy one
there is a lot of DES-OFB encryption in my area and most P25 scanners
receive encrypted transmissions and give you "gerbil talk"

I want the scanner to ignore/MUTE encrypted P25 transmissions can the SDS-200 do that ?

Thanks
Charles

It’s my understanding Uniden took the federal mandate that states no receiver should be capable of receiving encrypted comms quite literally and designed the SDS models (and the BCDx36HP models) to continue scanning when they identified a signal as being encrypted. I didn’t bother testing that because I lock out or avoid encrypted stuff. However, on occasion, I have heard encrypted transmissions on a TG or channel that is encrypted that I failed to avoid. The only thing you might glean from listening unintelligible transmissions would be an increase or decrease in the amount of transmissions. (A routinely quiet channel that got busy could be a good indicator that something is going on.)
 

n1chu

Member
Premium Subscriber
Joined
Oct 18, 2002
Messages
2,865
Location
Farmington, Connecticut
It’s my understanding Uniden took the federal mandate that states no receiver should be capable of receiving encrypted comms quite literally and designed the SDS models (and the BCDx36HP models) to continue scanning when they identified a signal as being encrypted. I didn’t bother testing that because I lock out or avoid encrypted stuff. However, on occasion, I have heard encrypted transmissions on a TG or channel that is encrypted that I failed to avoid. The only thing you might glean from listening unintelligible transmissions would be an increase or decrease in the amount of transmissions. (A routinely quiet channel that got busy could be a good indicator that something is going on.)

I should add, it wasn’t my intention to listen or attempt to listen to the encryption... I believe it was the scanner failing to identify encryption and it stopped and listened when it should not have. The short answer to your question is no, the SDS100 or 200 should not stop on encryption. Better yet, cherry pick an program in only those TG’s you will be listening to. And if the whole system is encrypted, don’t bother to load it at all.
 

jonwienke

More Info Coming Soon!
Joined
Jul 18, 2014
Messages
13,409
Location
VA
It mutes most encrypted stuff. There are a few variants of DMR and P25-II that aren't always identified as encryption and you hear garbles, but everything else is muted and skipped.
 

phask

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
3,745
Location
zanesville
It mutes most encrypted stuff. There are a few variants of DMR and P25-II that aren't always identified as encryption and you hear garbles, but everything else is muted and skipped.

It mutes all P21 PH1, I thought, and I may be wrong, that it does not mute PH2. Unless they finally figured it out and changed in a later FW, it was not possible to mute PH2.
 

jonwienke

More Info Coming Soon!
Joined
Jul 18, 2014
Messages
13,409
Location
VA
I've seen encrypted P25-II get skipped on some systems and played on others. It seems to be a bug in identifying encryption on some variants of P25-II (Harris vs Motorola???) but not others. Same with DMR, on some systems encryption gets skipped, on other you hear the garble. AFAIK there's no reason the bugs can't be fixed eventually. Encrypted P25-I seems to always get skipped.
 

phask

Member
Premium Subscriber
Joined
Dec 19, 2002
Messages
3,745
Location
zanesville
I've seen encrypted P25-II get skipped on some systems and played on others. It seems to be a bug in identifying encryption on some variants of P25-II (Harris vs Motorola???) but not others. Same with DMR, on some systems encryption gets skipped, on other you hear the garble. AFAIK there's no reason the bugs can't be fixed eventually. Encrypted P25-I seems to always get skipped.
I'm probably wrong, but seem to remember the "flag" was in the header data, if it missed the header you got the enc. Or something similar. P1 is different.
 

cagosti

Newbie
Joined
Feb 1, 2008
Messages
7
thanks for your help
my older Uniden P25 trunking scanner does not mute on encrypted transmissions and when I am just sitting on a control channel to see whats there
the encrypted transmissions comes out gerbil and its anoying as hell to listen to . around here fire and EMS are clear but PD is DES-OFB
 

trentbob

W3BUX- Bucks County, PA
Premium Subscriber
Joined
Feb 22, 2007
Messages
6,175
So my County uses apx 7000s. Our po's can encrypt any transmission they want if they feel they should but for the most part dispatch is in the clear.

They have plenty of Ops channels that are always encrypted if they need it so if a particular po leaves his radio on encryption on a Zone dispatch channel he's supposed to be reminded by the dispatcher that his radio is encrypted, it is reserved for a sentence or comment that that particular po wants to encrypt.

My apx7000 and my SDSs side by side... I hear a encrypted message loud and clear er... I mean loud and garbled on the SDS and it is silent on the apx 7000 which is not affiliated.

Some po's encrypt just about everything they say and by policy are supposed to be told by the dispatcher that they are on encryption, if he ignores her then he stays on encryption the whole shift. The dispatcher won't say it twice. I don't mind hearing the encryption because it's not that often on dispatch channels but at least I know a response was made that he did not want me to hear. My ears perk up and I pay careful attention to see what's going on.

This is a P2 simulcast system and it does not show ENC on the display when an encrypted transmission is heard.
 
Status
Not open for further replies.
Top