Ian

Both truly excellent ideas!  I'll be hitting them up on Twitter and mentioning it in any relevant Facebook groups I can find…
 
Signal amplification for the win!

Interesting question.  The Mod staff will let Rich know that there is an inquiry waiting here...

Thanks for the post.

Hey, we can see individual repeaters' coverage circles on the map.  
 
Is it possible, or at least reasonably feasible, to map all the repeaters' coverage circles simultaneously?  Especially if some can be disabled (as a couple repeaters in the database seem to be down for the count, and a few others seem to be down for repair or upgrades, according to email exchanges I've had).
 
Penny for your thoughts?

This is already permitted; see the Garmin Ring for more details.  This is only an expansion to GMRS channels.
 
 
 
Speaking of the Garmin Rino, enough people are willing to shell out $650 for an FRS radio that it's still in production a decade later, and with ever more smartphone-like hardware.  Hams use APRS, which has grown from a simple "amateur position reporting system" into a full-fledged tactical network (their words, not mine) which allow passing of email, instant message, position and status information…
 
I don't have any use for it, as nobody I communicate with has a ham ticket.  However, an in-dash GPS navigator / GMRS radio (god willing, GMRS repeater, too) would be amazing, especially if it was aware of repeater coverage circles and could seamlessly and automagically switch to simplex (one less thing to worry about).
 
A momentary tangent into commercial land-mobile radio and fleet management - they pay thousands of dollars to use satellite to pass quick voice messages and location and status of their vehicles in real time.  Clearly there's a use case, but mere mortals can't afford to find out if it suits them.
 
I'd like to be able to have a combination of turn-by-turn directions, and semi real-time GPS coordinate updates when I'm driving with someone else.  And geolocation bursts over GMRS are a perfect opportunity to unseat Garmin's Rino protocol in favor of APRS; this will allow other vendors to compete in that market and help drive prices down.  Furthermore, (knock on wood…) calling for help will include machine-readable GPS coordinates, which will direct help quickly and efficiently to the location of someone in jeopardy instead of requiring the organization of a search party or a helicopter with a thermal camera.
 
I'm even open to data bursts on repeater inputs, though with more trepidation - perhaps limiting them to manual triggering would be a good first step.  Or another option would be to offer cheap repeater controllers with multiple tones; data would be transmitted with one PL code embedded in a sub-audible signal -- Dakota Alert embeds triggering data for their MURS driveway alarms by modulating the CTCSS tone -- and a different PL code for analog voice, allowing a repeater to silently pass data without interrupting users of legacy hardware with the modem howl of modulated data.
 
Another possibility is silent slow data, and the use of the whole audio spectrum for loud fast data, embedding a callsign into an opening tone and a GPS coordinate into the roger beep?  I've done similar things with an Anytone I bought before their certification was pulled.  The preamble and Roger beep would embed the name of the user in such a fashion that compatible receivers would display their name or callsign on their display while they were talking.  It sounded like a cross between birdsong and modem sounds, and was perhaps an unpleasant roger beep to listen to, but it took no longer to transmit and was no more intrusive than one.

IF the LT-590 is just a limited version of the MXT400, and, one wanted to build a part-95 acceptable repeater out of “MXT400”s, then one could use the LT-590 as the receiver. I am not saying the receiver would, or would not, be selective or sensitive enough. But, if the MXT400 was de facto “good enough,” then the LT-590 should be too.

http://www.dovesandserpents.org/wp/wp-content/uploads/2012/04/facepalm.jpg
 
Edit:  Holy crap, the Midland is TWICE THE PRICE!!!  D:
 
Edit:  I'm morbidly curious to see if the LT-590 programming software would work on the Midland…

Hans, I'm going to slyly take what you're doing here and run with it.
 
Let's rationalize the entire Personal Radio Service.
 
MURS becomes part of FRS.  They're both allowed two watts, business use, and no repeaters, yes?
 
GMRS gains the ability to listen to repeater inputs (a blindingly obvious solution, in hindsight, from my ham radio study guide) and … let's call it eight 50 watt VHF channels.  Half will be repeater inputs, half will be repeater outputs.  Preferentially taken from the color-dot pool, since the market has matured, and business radios aren't sold with all of the available channels programmed in any more.
 
Yeah, actually, that'd be perfect.  In the mean time, Uniden (may) have me covered.  
 
Quarterwave:  The hardware's the problem.  What do you think about starting up group-buys on Massdrop for legal-but-unprofitable custom kit like better wireless mics?
 
If anything I said here would be done, merging FRS and MURS would be the golden ticket.  It'd reduce the number of boxes I carry every day.

Does this...
 

... conflict with that?
 

If I take a part 95 repeater in a trailer or in a Pelican box to a location and string up an antenna or put an antenna on a tripod or have an antenna on the trailer; is that a violation of part 95? There is no permanent structure.

Oh, crap.  I'll be doing this the manual way for the foreseeable future, then.  Thank you!
 
That's definitely the solution I'm leaning towards, if the $100 crystal-controlled Ebay special (it includes a tuned duplexer, sometimes!) doesn't happen to me soon.  I'll probably use Midland -- wait. They can't listen to repeater inputs.     I'll probably find the cheapest receiver I can, since unless contradicted, the best information I've found yet says that only the exciter has to be 95 certified.  (Read as a component of the transmitter, when used with an amplifier, or the whole transmitter, when used without.)
 
And no, it doesn't have to be pre-made.  I'm sorry if I gave that impression, as I'm well aware that borders on impossibility.  I just really want all the components to be replaceable on short notice if something goes belly-up on me.
 
 
 
It should only take a few mW from inside the car.  If this was Australia, I'd just get a Uniden UHF-CB, and the first party wireless mics, but they aren't even trying to make that available in the US, even though it's explicitly legal.  Wait, that's not true - they're only making them available with connectors for three high-dollar CB radios.  
 
Cross-band repeat would be simplest, but we __do__ have the option in GMRS, as I realized last night just before bed.  MotoTALK does about 0.7 watts of 900 MHz FHSS in the ISM band there, so with a custom cable and turning on vox on both the GMRS transmitter and the cellphone I'm using as a base for the "wireless mic", I really could have a cop-a-like system.  
 
Having said that, and with requests for more clarity in my needs, my "minimum viable product" is:  I want a garage repeater that'll cover the neighborhood and those stores I use the most 'cause they're closest.  I'm leaning towards using an Ed Fong J-pole attached to the chimney as a my antenna, and a cheap Chinese duplexer tuned so I can change channels on the repeater without visiting a radio dealer.
 
The first enhancement to this minimum viable product shall be a battery backup, for I live in Florida.
 
 
 
Understood and I apologize - I really muddied the waters by not clearly breaking this up into more sane chunks.  IE, garage repeater, car repeater, fun projects to add later.  Only thing I'm worried about is the ready availability of repair parts, thus the requirement that all components are still in production, though I suppose a sufficiently large supply of old stock might soothe my nerves.

Breaking this out for tl;dr -
 

http://www.nsea.com/Linking.pdf
 
Per the guy holding the oldest active GMRS callsign, an analysis of the rules of repeater linking.  WRAF213, I was about to tell you that you were probably wrong, but per the definitions provided by Cornell, I'm now inclined to think that "causing a station to begin transmitting" is specifically permitted by definitions, but they also say that you're not allowed to link in §95.127.  
 
 
 
This is definitely a hot mess, and trying to figure out what's legal gives me anxiety attacks.