17-03-2021, 22:59
(18-03-2018, 15:56)danner Wrote: That's inaccurate. Operation of unlicensed Part 15 Devices is permitted between 420 and 450 MHz and more specifically there is a sub-band from 433.5-434.5MHz that arduino transmitters use with the caveat that applies to all devices:
(1) This device may not cause harmful interference.
(2) This device must accept any interference received,including interference that may cause undesired operation.
Using 433 MHz is a bone head move.
It is right in the middle of the weak signal operation part of the 420-450 Amateur band. As a telecommunications engineer and Amateur Radio operator of 53 years, I have been personally consulted to remediate many interference complaints. Amateur Radio operators are very active on these frequencies and many are professionally engaged in the field. They know their way around and tangling with them is inadvisable. Amateur Radio is a licensed service and your weather station in NOT.
A complaint will end up in front of the FCC Field Enforcement Office. The FCC takes interference to licensed services VERY seriously. You will receive a "cease and desist immediately" order that you must respond to in writing explaining the circumstances and what you are doing to follow compliance with the order and what you have done to insure it will not happen again. This will probably end the case with the FCC unless you go ahead and use it again. If caught a second time after contact from the FCC, the gloves come off and you will need a lawyer and some disposable funds to get you out of that mess.
In any event, at this point, you will at least be out of your purchase money and stuck with a piece of gear you cannot use. I have seen it happen more than once. Ignorance of the law is no excuse.
Much of these Part 15 devices come from China. Recently, there have been many high profile, high forfeiture cases where US companies have imported Chinese electromagnetic equipment that did not meet FCC specs...hardly a surprise.
If you purchase any equipment that operates on 433MHZ and you lack a license, you will be at the mercy of licensed services. There are better Part 15 frequency bands than any of the licensed Amateur service...unless, of course, you can get a full refund years latter.
