There is nothing in Part 90 that prevents a multi-band device, Motorola, Harris and Kenwood both sell multiband P25 devices (V/U, U/800, V/LTE, et al). Motorola, Harris and Kenwood (tait as well) also support multiple trunking/signaling systems on the same device as well.

What you're running into is agencies not wanting to interop - GMRS is a special case, because its a licensed by rule service (Part 95), but everything else, everything public safety and commercial can all be loaded in one radio, legally and technically (GMRS will technically work, its just not strictly legal - but the rules for Part 95 are widely flouted) - it takes agencies buying multiband radios (they're expensive) - and agencies willing to cooperate to share system keys (and encryption keys) which they loathe to do, because it means giving up control.

Interoperability is a huge issue with public safety, and it wont be fixed by broadband, it will only be fixed when a bunch of people die directly because of it, and then the public demand something be done - these agencies have no incentive to cooperate (quite the opposite, they might get less funding if they did).

Yes, there are multi-frequency devices, but they are all in the same "range" or "band" or "grouping" of frequencies (whatever it is we're calling that).

I'm talking about a combination hi-band, lo-band, GMRS, P25, paging, etc. radio. I should be able to tune National Weather Service on it if I want to.

When I talk about this, ham guys get all huffy about FCC this and that and what kind of anarchy do I want to live in. Whatever.

What I am telling you is that, on the ground, it's a shitshow (with regard to physical radios) and it's frustrating to know that it's a political problem, not a technical one.

You can order a radio with High VHF, UHF, 700/800, 900, LTE or with any of the two above, Harris has the (it does something we affectionately call DC-Daylight - aka, the entire EM spectrum), SG-XG100 I think does basically everything, 30MHz to 1000MHz.

Low Band is a special case, because of the sheer antenna size, which is huge, and unwieldily low band handhelds are also near useless.

Ignore the ham guys, they dont know much about part 90 (other than they are correct that the Baofeng Radios are probably not type accepted.).

It doesn’t help that the protocols are all proprietary and/or encumbered with patents. An open source version of Brandmeister would go a long, long, way.

None of the protocols are encumbered, P25 and DMR are both open standards - the audio codecs they use however, are not.

Brandmeister wouldn't fix anything in the public safety space as nothing in public safety is DMR.

> Imagine I respond to a car accident and need to call for a helicopter and arrange a landing zone. In this situation, I will be juggling four brick sized radios throughout the duration of that call.[1] Possibly while driving.

Oof, that's painful. Airlift here has their choppers programmed with all the VHF and UHF frequencies for effectively every county in Western Washington.

> The issue is the FCC "typing" rules that disallow a single device operating on multiple, disparate frequency bands.

My phone that connects to multi band WiFi, Bluetooth, NFC, wireless charging and 2g, 3g and 4g disagrees with that statement.

Without much knowledge about the process: Is it a problem to have it handled via some centre? I.e. you're asking X to dispatch all of those requests for you which would free you up to drive? (And get either one of those calls connected directly to you as needed)

Exactly this. I spent decades as a FF/EMT and that's the way it was typically done.

I did however, often carry a Baofeng programmed with _all_ the services with which I was likely to interact as a backup: MedEvac, EMS, law enforcement and fire services. Yes, I am a licensed ham operator.

The problem is there is no national emergency interop frequency plan, each state, county and city does things differently.

DHS publishes the National Interoperability Field Operations Guide which includes a national channel plan for calling, simplex and deployable repeater operation.

Each state/county/etc. may have different licensing, but they are also encouraged to program the NIFOG channel plans when space is available on radios.

One of the proposed benefits of 4G/5G is that they can make microcells that can do exactly that, with the client devices being regular phones.

Well, it seems ridiculous to say that, because there have been 3g microcells (openbsc, for example) forever. It seems bizarre that we couldn't have a switch in every truck that turns it into a mobile microcell for <$100. The backhaul is the problem, because normal microcells are connected to the internet via hardline IP communication . . . . which could be done with modern satellite. The problem is that if you are selling anything to any kind of government agency, you absolutely want them _not_ to be able to use any commodity component like a "cell phone"

Motorla sells LTE enabled radios, but changing from a narrowband air interface to a wideband one doesnt get you much, terrestrial can work in these situations, they dont need phone calls, they need radio and data communications - mostly data.