looking for a PIC

[dhouston]

Well, if it happens it will involve about 50 total keyfobs (at least, initially) that will be deployed in a mountain valley (in the Flagstaff area) where cell phones are useless. Given the terrain and the fact that they will be activated only in a medical emergency, I doubt there will be any significant interference issues but the potential for FCC problems is one more thing to consider. They have introduced one new condition that may force me to withdraw anyway.

I had a radiotelephone license about 50 years ago when I finished USAF electronics training but never worked in the field and have never done anything that required approval. It sounds as if you are active with current FCC contact but I doubt many people would find it necessary to seek approval for this.

And, yes, it is a 12V battery. Most remotes like this and even wireless doorbells use a high capacity 12V battery.

There is one other possibility. I might be able to provide a replacement MCU (perhaps of the same type) for the receiver/dialer unit. I'll have to borrow one of theirs to see what that would involve.