433Mhz vs 868Mhz

[Lastcaress]

Hi,
I've been playing around with arduinos for a while but only recently focused my interest in these low power modules with lora. I'm going to order a monteinousb and a LoRa OpenWrt IoT Gateway and I have the choice between 433 and 868mhz.I was inclined to buy the 868mhz versions, but I order a lot of arduino stuff from chinese stores and they have a LOT more offers in the 433mhz range, so I really don't know what to chose. I'm in europe where both bands are legal and all projects are personal hobbies, just something to keep me busy!
Thanks!

[captcha]

Generally speaking, lower frequencies will penetrate better through common obstacles such as air, trees, floors and walls. All things being equal, the most visible change on the radios is the use of physically bigger antennas on lower frequencies. Power consumption-wise the difference is negligible. If you're inclined to get your ham-radio licence at some stage (not required for these low-power radios btw) you may find that the 70cm band (433MHz) is also open for further experimentation to you. This is probably why you see more choice online in antennas for 433MHz.

Which radio you should get may be just a matter of how much space you have for fitting an antenna in/on your project. If however you're trying to get 10km range out of these modules I would go with 433MHz as the lower frequency signals travels further and you'll have more choice of finding off-the-shelf high-gain antennas for that band.

[Lastcaress]

Thanks for the reply! Space won't be a problem. So there aren't any downsides to get a 433mhz one ? (interference because it's used by so many things, or being less futureproof?)

[captcha]

Without doing a wireless survey where you will be using these devices it's impossible to say what the conditions are that your project will be subjected to. The good thing is that approved transmitters for these class-licenced bands are all low power, so their effects shouldn't be affecting a large area. On the other hand it's also a free-for-all place, meaning that you cannot complain to any regulatory body if (within spec) transmitters are giving you a difficult time. But you'll have that at 868MHZ and 915MHZ (and 2.4GHz and 5GHz) as well. Welcome to the ISM band.

I can't make many predictions about the future but I'd say that more and more devices will be using higher frequencies because of their higher data-rate requirements. If anything I'd say that the lower frequencies (e.g. < 1GHz) will keep their ISM allocations for many years to come.