Anyone know if you can LEGALLY transmit MT63-2k messages on FRS/GMRS?
I’m looking at alternatives to the [very-tempting] Garmin RINOs. Since I always have a phone with me (but don’t always have coverage - such as in an emergency involving power outages), that means I already have a GPS with me (Garmin GPS in RINO is redundant). If I could transmit GPS position audibly using MT63-2k and a smartphone app, and LEGALLY broadcast said-data on GMRS/FRS, I would be close enough to RINO-ville that I wouldn’t drool over them anymore.
I’m going to ‘bump’ this one, as I still haven’t found an answer. In fact, it dropped off my radar for so long I forgot about this post. I was Googling for a solution, and came across this post… my own!! :eek: I was thinking “Finally, this guy knows what I’m talking about… wait a…”
So here’s the scenario: two boats/kayaks on the Chesapeake Bay with no cell coverage. I want to send my position to the other vessel. Here are my options as I see them:
[li]Garmin RINO
[/li]Easy, but $$$ and extra gear to carry (I would need at least two RINOs)
Great GPS (but is redundant because of cellphone) but poor radio (and no removable antenna)
[li]HAM / APRS
[/li]More gear to buy and I don’t see all ‘vessels’ (myself included) getting HAM-certified
[li]‘Speaking’ into Marine VHF (or GMRS)
[/li]“I am at latitude four three point seven six five…no, wait…” Ugh
[li]goTENNA
[/li]$$ But kind of a neat idea - texts and position sent digitally off the grid
Extra gear to carry (or lose/ruin in the water)
[li]** Digital over Marine VHF or GMRS **
[/li]‘Acoustic Coupling’ using MT63-2k (or whatever)
Transmission is preceded by “This is WQTxxx, standby for MT63 position transmission…”
Other station (boat/kayak) acknowledges and sets up to receive/decode
GPS position from smartphone on sending station (don’t need cell signal for that) is converted to ‘audible’ signal (modem) which is played on speaker and transmitted by keying mic on VHF/GMRS
Signal is received by radio and decoded acoustically by smartphone app and displayed on offline map
So, the questions:
[ol]
[li]Is the last option (MT63) legal? Can I send 'encoded(?) messages like my position over marine VHF and/or GMRS?
[/li][li]Is there a better way???!
[/li][/ol]
Thanks in advance!!
The answer to your questions may depend somewhat your country. Within the US:
I would not send a audible digital signal over marine frequencies intended for voice communications.
Newer Marine radios equipped with Class-D (DSC) Digital Select Calling capability already support GPS using NMEA standards. As of January 20, 2016, the FCC requires fishing and small passenger sea vessels operating within certain areas of US waters must be equipped with with a Class-D DSC marine radio and GPS. Radios such as the Cobra MR F77B/F77W feature a built-in GPS receiver. It automatically sends your location with DSC calls to other vessels and displays coordinates on the front panel screen. Some makes and models of VHF marine radios work with optional external GPS modules or add-ons.
To answer your question as to whether or not it is permissible to send digital data over GMRS, the FCC rules state:
e) All messages must be in plain language (without codes or hidden meanings). They may be in a foreign language, except for call signs (see ?95.119).
(f) A station operator may communicate tone messages for purposes of identification or transmitter control in a control link.
(g) A station operator may communicate a selective calling tone or tone operated squelch only in conjunction with a voice communication. If the tone is subaudible (300 Hertz or less) it may be communicated during the entire voice message. If the tone is audible (more than 300 Hertz) it may be communicated for no more than 15 seconds at a time.
(Source: FCC Rules Title 47 → Chapter I → Subchapter D → Part 95 → Subpart A → ?95.181)