Hmm I think you’re right that digital voice protocols aren’t allowed on in 462-467 MHz FRS band. But there are a couple regions of the 900-1000 MHz portion of the spectrum that are allocated to commercial two-way radio, which allows digital and might be usable for this application if you were trying to actually manufacture and sell this kind of product.
If one were trying to do this as a homebrew project, either the 902-928 MHz ISM band used by the XBEEs or the 420-450 MHz band used for ham radio could work (with a ham radio license).
Hmm I think you’re right that digital voice protocols aren’t allowed on in 462-467 MHz FRS band. But there are a couple regions of the 900-1000 MHz portion of the spectrum that are allocated to commercial two-way radio, which allows digital and might be usable for this application if you were trying to actually manufacture and sell this kind of product.
If one were trying to do this as a homebrew project, either the 902-928 MHz ISM band used by the XBEEs or the 420-450 MHz band used for ham radio could work (with a ham radio license).
I think at that point you might as well use a cell phone watch?