Hacker Neue

Preferences
patwolf parent
For anyone looking for an off-the-shelf solution for wireless texting, I've used the BTECH GMRS-PRO. You can send messages on the device, but it's much easier to connect it to your phone via BLE and text through the app.

However, it uses GMRS bands, not LoRA, so all the FCC restrictions apply.

threemux
While I highly doubt you'd ever get in trouble, data transmissions on GMRS are severely restricted by the FCC. You obviously need the license (though it's just a fee and covers your whole family).

In any case, I'm pretty sure this device is illegal to use for short text messages. It doesn't appear to comply with several of the restrictions on digital emissions in 47 CFR 95.1787(a), namely it appears to have a removable antenna. Removable antennas are fine for regular GMRS use, but not when the device can send digital emissions.

https://www.ecfr.gov/current/title-47/part-95/subpart-E#p-95...

Also I'd be shocked if it enforced the time limits for digital transmissions in software. This leads me to believe it's not actually type-certified for use which then calls into question anything else it does. Caveat emptor.

patwolf OP
The antennas on mine don't appear to come off, at least not easily. I read somewhere that they came off on the early models but are now glued.

It does enforce time limits. If I send a message or something that uses digital communication (like gps coordinates), it won't let me send another one immediately after.

threemux
Wow I'm surprised - I based my message of the manual on their site which pretty clearly shows a detachable antenna and says nothing about time limits. I wonder if they received something from the FCC saying they can't market a GMRS radio that isn't type-accepted.
jpalawaga
Why wouldn’t they comply with tx duration? You don’t want excessively long tx as you can’t rx at the same time. You’ll lose messages.
threemux
There is no amount of time that guarantees you won't interfere with another user on a shared channel without time division. Any protocol used has to account for it no matter what.

But discussion of that is irrelevant because the regulation is no more than one every 30 seconds and each one can't be longer than 1 second in duration. This necessarily limits the length of messages you can send or requires more efficient modulation and/or weaker error correction at the tradeoff of worse weak-signal performance.

etrautmann
Can you elaborate on the restrictions? Is it just that the Baofeng allows you to transmit on some frequencies that aren’t legal or at power levels that aren’t allowed or is it not allowed in the US at all?
pastorhudson
To use GMRS you need a license to be compliant with fcc. It’s not expensive I think $60 for 10 years and it covers your family.

You can then use GMRS. GMRS is all the same FRS channels plus several more. GMRS can also transmit at up to 50mw on some of the non-FRS channels.

To be using GMRS in compliance you have to use an FCC Part 95E certified device. These Baofeng / Btech devices are usually not GMRS certified. So you need a HAM license to use them. . . But HAM licenses doesn’t cover GMRS frequencies. So there is no technically compliant way to use these devices and check all the boxes. Even if you have both HAM and GMRS you are using a non Part 95E certified device. You’re likely fine as long as you’re not harassing people or causing interference. Generally the FCC is pretty reasonable. They send a letter saying knock it off before they knock on your door. But if you continue to harass people or use high power that causes interference then you will get a hefty fine.

At the very least get your GMRS license. But I encourage you to get your HAM license. I have found that often HAM nerds are into a lot of other stuff I like and my local club has been a welcome place to make friends and build fun stuff.

codys
Btech markets devices that are GMRS type accepted, it's actually one of their main businesses these days to take Chinese developed radios and modify them slightly and get them GMRS approved in the US.
sidewndr46
I think you said "50mw" when you meant "50 watt"
sejje
You need a ham license to do most anything with a Baofeng legally.
bityard
Baofeng does make GRMS- and FRS-specific radios that comply with FCC regulations.
kingkawn
Not true, GMRS licenses are much easier to get
wildzzz
While true, it's important to remember that not all ham radios that can transmit on GMRS bands are legal to do so. GMRS and FRS don't have the same "anything goes" allowances that ham operators have. Radios for these bands must be purpose built for these bands. Of course no one is going to know your compliant GMRS/FRS transmissions are coming from part 97 radio. Although most quality ham radios don't allow transmission on anything but the ham bands. The increased FCC enforcement of these Chinese radios means that many now have extra filters to reduce spurious emissions outside the ham bands, meaning they shouldn't work as well on GMRS and FRS.

If you want to use GMRS, buy a GMRS radio.

7402
>not all ham radios that can transmit on GMRS bands are legal to do so.

Actually, no ham radios that can transmit on GMRS bands are legal (in the US).

See 47 CFR 95.1761:

https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D...

tejtm
No licence is required to listen to any frequency.
sidewndr46
Not event remotely true in the US. Reception of cellular radiotelephone signals is prohibited by law unless you are a participant in the conversation.
subscribed
*in some countries.

This item has no comments currently.

Keyboard Shortcuts

Story Lists

j
Next story
k
Previous story
Shift+j
Last story
Shift+k
First story
o Enter
Go to story URL
c
Go to comments
u
Go to author

Navigation

Shift+t
Go to top stories
Shift+n
Go to new stories
Shift+b
Go to best stories
Shift+a
Go to Ask HN
Shift+s
Go to Show HN

Miscellaneous

?
Show this modal