A case aginst open sky and other patented systems

[brey1234]

Recently, some U.S. public safety and critical infrastructure agencies have opted for digital LMR technologies that are not compatible with P25. “Not only does this pose a virtually insurmountable technical hurdle for successful interoperability, it potentially negates billions of dollars' worth of investment in P25 LMR systems,” NPSTC said. “The use of incompatible equipment will create a barrier to achieving interoperability and therefore increase the risk to our first responders and the public they serve and protect.”

MissionCritical Communications, Radio Resource International, and Public Safety Report - wireless voice and data communications for mobile, remote and public safety operations

 

[PACNWDude]

Interoperability, keep an analog channel.

Everywhere I have ever worked: military, public safety and emergency response, inter-operability is the key catch phrase. Some entities spend millions of dollars on Centracom consoles, Gai-tronics gear, Telex interface boxes, IP-223/224's, Raytheon ACU-1000's.

In every case the best and most likely to succeed solution is also the simplest one. Keep some analog channels that every radio built and fielded still to this day can operate on. If you are smart, you keep some VHF/UHF and 800-900 MHz analog channels free for this use.

And for the Motorola,Harris and Thales reps in here, make a multi-band radio that has AM as well as FM functionality.

There are customers that will pay for a civilian encryption free version of the PRC-152 or PRC-148 that costs between $3-5k. Current models are still a bit too expensive for widespread use and AM and marine VHF frequencies are still used quite often. (When applicable.) Where I work now, we operate on the water and near shore, so there are marine VHF frequencies as well as aircraft we need to talk to.

 

[DisasterGuy]

I really see no use for AM above 30MHz - with the exception of aircraft. When it comes to aircraft, if you have a genuine need to talk on airband frequencies, you should have a FCC Ground Station license and either be using a spec radio (such as the Icom IC-A110) or do as we do and have a patch from a system talkgroup to UNICOM and your local airport's CATF.

 

[PACNWDude]

A-110 Icom in use, but Harris Unity AM would be perfect.

We do use patching equipment and Icom A-110 radios to speak with aircraft. The Icom A-110's are mounted on board larger ships. However, for smaller vessels they need patched through from the larger vessel. So in this case if any of the larger radio mfr's made a handheld radio with AM capability. They could sell several thousand to my employers and the entire industry.

The aircraft are offshore and nowhere near an airport. So the infrastructure has to be brought to sea. When comms go down offshore, things go bag. For that reason, everything gets backed up by satcom and HF.