GMRS for LA Riots.

[WSHH887]

Not sure why all the concern about phones. If you are there someone likely recorded you on their phone and has already uploaded it to social media. 

[WRYZ926]

11 minutes ago, WSHH887 said:

Not sure why all the concern about phones. If you are there someone likely recorded you on their phone and has already uploaded it to social media. 

This is true.

We got away with way more when we were kids compared to today's kids. There were no cell phones and not many had the 16mm cameras to record stuff. And one could just throw away any photographs and negatives.

On topic.

It is pretty easy for law enforcement and the military to monitor and track two way radios and cell phones. They can't hide unless everyone leaves all electronic devices at home. Some people have had warrants issued or have been arrested by using cell phone data and/or security camera feeds.

[LeoG]

I would say a 2 way radio is harder to find than a cellphone is.  You can ping a cell phone at will with the proper equipment and have it give it's position away.  You can't do that with a normal 2 way radio.

[TrikeRadio]

3 hours ago, LeoG said:

I would say a 2 way radio is harder to find than a cellphone is.  You can ping a cell phone at will with the proper equipment and have it give it's position away.  You can't do that with a normal 2 way radio.

Yeah, depends on what they are using to try to locate a cell or radio. I understand it is possible (for those authorized) to tell what cell tower is receiving the original cell phone signal which gets you in the area. I suppose with proper authorization they could figure out the photo and narrow the location down further by GPS. Two way Radios on the other hand would require triangulation by antennas near the transmitter and would still only give a general area location. 

plus, a phone (or phone network)  probably retains locations and timestamps that can be used afterwards to establish where someone was at a particular time after the fact. so... there is that. 

[WSHH887]

Curious. Don't some radios now have GPS?  Would these retain data?  Do some radios possibly have GPS unbeknownst to the purchasers that logs data?

[TrikeRadio]

1 minute ago, WSHH887 said:

Curious. Don't some radios now have GPS?  Would these retain data?  Do some radios possibly have GPS unbeknownst to the purchasers that logs data?

I don't know a lot about the 2-way radios that have GPS built in. I know that they can transmit their coordinates to another radio (that has authorization? ) in some manner. No idea if they retain a history with timestamps.

[WRUE951]

39 minutes ago, WSHH887 said:

Curious. Don't some radios now have GPS?  Would these retain data?  Do some radios possibly have GPS unbeknownst to the purchasers that logs data?

some Radios do have GPS and transmit their coordinates to other grouped radios but only when the feature is programed or activated in the radio..  Some of my radios have GPS features but i dont have them programed in my radios, therefore none of this data would be transmitted from my radio.  

[LeoG]

Wonder if it's hardwired in there that law enforcement could force the info out of it with a special code.

[TrikeRadio]

17 minutes ago, LeoG said:

Wonder if it's hardwired in there that law enforcement could force the info out of it with a special code.

I don't think there is any reason or even memory chips to retain GPS history in them is there? I would think it generates the GPS coordinates as needed when sending them as needed. But maybe some could store a limited history. anyone know? 

[LeoG]

Just asking.  Not sure how the GPS would work or be stored, or not.  In a phone it's extensive.  Goes back days, weeks, months..  I'll bet it's just on the spot for the radio.

[WSHH887]

Radios today are basically computers that transmit radio signals.  If it has GPS it could store info without the user knowing.  And as I posited a radio could include GPS and data storage the owner never knows about.  And if so, it may not be possible to disable the GPS.  And it would be quite possible to have it on even when the radio is "turned off".  At least until the battery died. 

[LeoG]

2 minutes ago, WSHH887 said:

Radios today are basically computers that transmit radio signals.  If it has GPS it could store info without the user knowing.  And as I posited a radio could include GPS and data storage the owner never knows about.  And if so, it may not be possible to disable the GPS.  And it would be quite possible to have it on even when the radio is "turned off".  At least until the battery died. 

Most radios have a physical off switch unlike phones which have electronic on/off switch.  No power is no reception/transmission.  They could sneak in a bypass resistor to keep the power on for the GPS.

[WRUE951]

17 minutes ago, LeoG said:

Most radios have a physical off switch unlike phones which have electronic on/off switch.  No power is no reception/transmission.  They could sneak in a bypass resistor to keep the power on for the GPS.

The radios I have with GPS (Hytera) must be turned on in the program mode and programed how you want to xtmt/rcv GPS data. I can set GPS data to specific groups and not to other groups.  If you dont have it set to send your GPS data to a specific group, nothihesng is sent, However i can set up in programing to receive GPS data from a certain group.  .  I have played with this but never really saw a need for it so i ignoree GPS in programing  (off).. A local 4-wheeler group uses GPS in their readios to ping their locations when 4 wheeling..  Take note, Radios with GPS need to be 'like' radios as their GPS function are proprietary to the radio brand.  My Hytera radios with GPS wont work with Motorola or ICOM and vis versa.  

[WRYZ926]

8 hours ago, LeoG said:

I would say a 2 way radio is harder to find than a cellphone is.  You can ping a cell phone at will with the proper equipment and have it give it's position away.  You can't do that with a normal 2 way radio.

It depends on the agency and what equipment they have available to them.  I know that 20-30 years ago, we had equipment in the military that could triangulate a transmitter quickly. 

Even today's systems such as the Kraken SDR can pinpoint a transmitter fairly quickly, and two or more Krakens in different locations and the time to pinpoint a location goes down. One Kraken will get you pretty close and do so in a reasonable amount of time. 2 Krakens will do it quicker and with more precision. Three or more Krakens will be even more accurate and take less time.

[Blaise]

You need to look out for those krakens...

[SteveShannon]

10 minutes ago, Blaise said:

You need to look out for those krakens...

Transmit briefly and move frequently. 

[LeoG]

It might be difficult even for a few krakens to locate FRS/GMRS radios especially if there are many signals on the same frequency.  Lots of "ghost" signals that keep moving around.

Maybe 3 airborn detectors triangulating with high power optical recorders might be able to do the job quickly.  And I don't doubt they have such a system.  But with lots of radios out in a relatively small area it might be difficult to lock on a single tranceiver and even harder to hear a single transmission in a sea of similar signals. Don't use a roger beep or any identifying transmission.

[WRUE951]

find a big huge round ground water tank and splatter your signal everywhere as you drive in circles around it .   

[WSHH887]

1 hour ago, SteveShannon said:

Transmit briefly and move frequently. 

 

that was the idea when using the AN/PRC-90.  I just missed the AN/PRC-103 that was a pretty good improvement.  There was a movie about a downed flyer.  There radio discipline was pretty terrible and had they used the radio as much as they did in the movie it would have died or the flyer would have.  The north Vietnamese knew what frequency to monitor.

[WRYZ926]

1 hour ago, LeoG said:

t might be difficult even for a few krakens to locate FRS/GMRS radios especially if there are many signals on the same frequency.  Lots of "ghost" signals that keep moving around.

The Kraken system is like a child's toy when compared to what federal agencies and the military have. Even the equipment we had in the 90's was still better than the Kraken. We had no problems triangulating exact Iraqi positions back in 1991. And don't think for a minute that the feds are not using that kind of equipment right now.

 

24 minutes ago, WSHH887 said:

that was the idea when using the AN/PRC-90.  I just missed the AN/PRC-103 that was a pretty good improvement.  There was a movie about a downed flyer.  There radio discipline was pretty terrible and had they used the radio as much as they did in the movie it would have died or the flyer would have.  The north Vietnamese knew what frequency to monitor.

Transmitting briefly is standard SOP when using any military radio and has been for a long time. Transmit too long in a combat zone and you will get a missile or artillery rounds down your throat.

[WSHH887]

17 minutes ago, WRYZ926 said:

The Kraken system is like a child's toy when compared to what federal agencies and the military have. Even the equipment we had in the 90's was still better than the Kraken. We had no problems triangulating exact Iraqi positions back in 1991. And don't think for a minute that the feds are not using that kind of equipment right now.

 

Transmitting briefly is standard SOP when using any military radio and has been for a long time. Transmit too long in a combat zone and you will get a missile or artillery rounds down your throat.

My military radio usage was over 50 years ago, so things likely have changed a bit.

[WRYZ926]

1 minute ago, WSHH887 said:

My military radio usage was over 50 years ago, so things likely have changed a bit.

SOP hasn't changed, one still has to keep transmissions short to keep the enemy from triangulating your location.

The Russians and Ukrainians are finding that out the hard way. Difference is you now have to worry about drones along with missiles and artillery. Signals are scrambled and most military radios use frequency hopping but the can still be located if they transmit too long.

[WRTC928]

10 hours ago, WSHH887 said:

There was a movie about a downed flyer.  There radio discipline was pretty terrible and had they used the radio as much as they did in the movie it would have died or the flyer would have.  The north Vietnamese knew what frequency to monitor.

True, but if they had used the radio as little as they probably really did, the movie would have been much less exciting. I believe you're referring to Bat 21 which was supposedly based upon an actual incident. I give Hollywood a little slack on some of these things. Nobody wants to see a movie about a bunch of soldiers who spend 20 days standing around scratching their b@lls and then have a 3.6 minute firefight.

[Lscott]

10 hours ago, WSHH887 said:

The north Vietnamese knew what frequency to monitor.

It was also known the NV had captured US man pack radios. These where used to monitor military communications. There were versions with encryption, but were extremely bulky.

https://en.wikipedia.org/wiki/NESTOR_(encryption)