Walkie-Textie Wireless Communicator
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Walkie-Textie Wireless Communicator
1–10 of 130 posts
Re: Walkie-Textie Wireless Communicator
#2Neat! At 24mA the suggested battery will only last 10 hours.
Shouldn't it be possible to use such a LoRa device - at least in listening mode without an active display - for much longer time periods?
Re: Walkie-Textie Wireless Communicator
#3It's very beautiful, but are there apps that do this? Isn't that what Briar does? I think there may have been some others.
Amazing work with an ATtiny814, only 8KB. Love it.
Re: Walkie-Textie Wireless Communicator
#4For 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.
Re: Walkie-Textie Wireless Communicator
#5If you want something like this with asymmetric encryption, a qwerty keyboard, mesh range extension, and a GUI, try a T-Deck running Meshtastic.
Re: Walkie-Textie Wireless Communicator
#6For 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.
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?
Re: Walkie-Textie Wireless Communicator
#7For 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.
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?
You need a ham license to do most anything with a Baofeng legally.
Re: Walkie-Textie Wireless Communicator
#8Neat! At 24mA the suggested battery will only last 10 hours. Shouldn't it be possible to use such a LoRa device - at least in listening mode without an active display - for much longer time periods?
LoRa is actually pretty thirsty on receive.
You’d need some scheme for synchronization if you want to reduce power consumption.
Re: Walkie-Textie Wireless Communicator
#9It's very beautiful, but are there apps that do this? Isn't that what Briar does? I think there may have been some others. Amazing work with an ATtiny814, only 8KB. Love it.
The distinctive element here is the hardware. Briar allows you to sync via local wifi and bluetooth (i.e. the range is tiny) but since it's a mesh network your message will be relayed eventually.
This device though doesn't seem to support mesh connectivity because it doesn't have this short range limitation in the first place. It uses a LoRa chip with a range of a few kilometers. The bandwidth is tiny though, for reasons that are both technological and legal. In particular your are asked to respect a duty cycle of 1% (or even 0.1%, depending on the exact frequency you're using). That's 36seconds every hour. On top of that add some cities offer LoRaWAN gateways (between LoRa devices and the internet) and the limits are even more drastic like 10 messages per day, 51 bits being the maximum payload length.
LoRa was designed for async metering of IoT devices basically. This application is pushing it to its limits I guess.
I'm not an expert, I have a couple LoRa chips but never used them, however here are some back of the napkin calculations:
Assuming a spread factor of 12 (very long rage, very low bandwith) and a 1% duty cycle, you can send about 40 messages per hour if they are short like "yo what's up". 50 chars -> 20 messages/hour. 100 chars -> 10 messages/hour.
Re: Walkie-Textie Wireless Communicator
#10For 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.
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.