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Comment by linksbro | Hacker News Reader

It transmits via some sub-1ghz free spectrum bands, which travel a good distance and have decent structure penetration. https://beartooth.zendesk.com/hc/en-us/articles/216797018-Wh...

This is why unlicensed spectrum bands are great; they allow for stuff like this to be built without a billion dollar spectrum price tag.

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Anyone else think its kinda sketchy that they're just saying "sub-1Ghz" frequencies? There aren't a ton of options there, and they aren't secret information. This sounds like they're either heavy on the vaporware side of things and haven't figured out what they're doing, which doesn't bode well for them shipping anytime soon, or they are trying to do something which the FCC isn't going to approve, which again doesn't bode well for us getting this thing on pre-order

Anyone know if they're encrypted? I'm not seeing any mention of that, I think I might grab a goTenna if only for that reason

>Anyone else think its kinda sketchy that they're just saying "sub-1Ghz" frequencies?

No. Why is that sketchy?

It's probably because it's different from their competition and they don't want to release that signal yet. I don't remember GoTenna pre-releasing their exact frequencies either.

~900MHz is pretty common for this sort of thing. I have a friend who uses the 900MHz spectrum for communicating with a hobby weather balloon.

I don't think 2 miles is a good travel distance. (or maybe it is from a technical perspective but not from a practical one).

That would assume lots of users which I feel can be problematic with a $399 price range and big form factor.

This is why selling to consumers is difficult. Consumers complaining about price is a given. An enterprise solution could be sold for much more.

Solving a business pain vs a consumer nice-to-have.

I've been trying to solve an issue similar to what Beartooth is doing, and 2 miles is amazing range. Bear in mind, these aren't huge towers hundreds of feet above the ground with 50kWh power sources and million dollar price tags, they're battery-powered, handheld, and consumer-priced. And cell towers with all the advantages listed only travel less than 20 miles. 2 miles with those limitations is a great distance.

I think maybe you're looking at the wrong use case. This doesn't replace GSM, it replaces walkie-talkies (or rather updates it for the text-based world). The use case is you and your friends are at an event downtown and cell service goes out (like it does when the sites are oversubscribed). You're camping and there's no service that far in the woods. You're in a disaster and trying to find your loved ones. It's short range communications, not long-distance calling.

Ham radio would go farther, but sending encrypted communications over ham radio is illegal, so that's right out. This is the next best thing.

...or you're on a small farm that's half a mile on each side and you need to know that the gate on the opposite corner from the farmhouse is still closed.

A minor change of perspective and suddenly a 2 mile range is fantastic!

Ham can do text and digital voice over e.g. D-STAR. https://en.m.wikipedia.org/wiki/List_of_amateur_radio_modes

Encryption to obscure your communication is technically against the rules, but things like D-STAR need a proprietary decoder (the spec isn't open) to be decoded, so some people consider that encryption even though it's pretty popular and not being shut down: http://www.amateurradio.com/encryption-is-already-legal-its-...

D-STAR is actually an open standard.

The only part that's closed is the voice codec (AMBE). But if you just want to transmit or decode data packets, you can definitely build your own hardware. There's even a couple SDR modules for it:

http://www.flexradio.com/amateur-products/flex-6000-signatur...

http://www.rtl-sdr.com/listening-d-star-digital-voice-dsd-1-...

  2 miles is amazing range. Bear in mind, these aren't 
  huge towers hundreds of feet above the ground with 
  50kWh power sources and million dollar price tags, 
  they're battery-powered, handheld, and consumer-priced

This guy did 7,600Km at 10mW on the 30m band, using a raspberry pi and a couple passives: https://gerolfziegenhain.wordpress.com/2013/04/13/raspi-as-w...

Of course, the antenna was 44 feet long, and he was transmitting at 1.46 baud, using WSPR: https://en.wikipedia.org/wiki/WSPR_%28amateur_radio_software...

As Shannon proved in the 40s, you can get great range if you can sacrifice bandwidth: https://en.wikipedia.org/wiki/Noisy-channel_coding_theorem

It's true that you don't need much power if both parties have ham radio licences, 44 foot wide antennas hoisted 30 foot into the air, and are willing to transmit unencrypted and very slowly. License-free handheld consumer gear is basically limited to UHF, which is pretty much line-of-sight.

I mean, using a 44 ft long antenna is kind of what I was talking about. This thing has zero external antenna.

>Ham radio would go farther, but sending encrypted communications over ham radio is illegal, so that's right out. This is the next best thing.

How come? I don't know much about ham, but it doesn't seem like it'd make much sense to make it illegal.

Ham radio spectrum is strictly for non-commercial use. If encrypted communications were allowed, it would be a lot easier to sidestep that with plausible deniability.

What frequencies are they using (sub 1ghz with audio) ? is 2 miles really possible ?

It states 2 devices for $249 at the top of the page.

With enough users on the network, wouldn't you be able to fairly easily extend the range by using idle beartooths as relay devices / amplifiers? Similar to how packets travel through the Internet.

That's not at all similar to how packets travel through the internet. Mesh networking is a very complex arena that deals with many issues that don't have known good solutions.

Not sure if it's true for this configuration, but I know for GoTenna (a competing product), the terms of use of the unlicensed frequency bands forbid message relay.

How does thing scale with user density? That's what I want to know. If everyone at a concert had one of these, would it still be useable? Unlicensed spectrum could already be crowded or noisy

I assume they mean the 900mhz band in the US. How is a cell phone supposed to communicate with the Beartooth? If its not a cell tower, the phone only knows bluetooth and wifi on 2.4/5Ghz.

> How is a cell phone supposed to communicate with the Beartooth?

Given the name, I would presume Bluetooth.

Piggybacking here but the FAQ is painfully vague. On the question of what phones does it work with their answer is:

> Beartooth pairs with both iOS and Android smartphones, as long as the operating system is up to date.

Which is a pretty much useless statement on Android especially since they would know what API level their app targets...

It certainly sounds like it'll use Bluetooth though and makes sense as a bridge between the two devices. The only other real option would be Wifi or if you wanted to be weird for the sake of it you could probably do it through NFC.

https://beartooth.zendesk.com/hc/en-us/articles/217369867-Wh...

My GoPro creates a wifi network and the phone just auto-connects to that to control the GoPro. So certainly the Beartooth could create a wifi network that the phone connects to and essentially sees the Beartooth as a traditional wifi network.

True it's certainly an option though for low rate text and data like the Beartooth is using WiFi is a bit of overkill and the power overhead makes Bluetooth more appealing than Wifi. That and how much they repeat 'pair' instead of something like tether made me think it was probably Bluetooth.

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