Max had a car that would learn the remote code and save it in it's internal memory. Of course that was probably only for that one frequency group that was used at that time. But the system that used that 9.??? megahertz crystal was in an entirely different frequency range, and probably used a totally different scheme of coding as well.
So Cmartinez has a system that in my guess uses one of the citizens band remote control channels, or just above the regular CB frequencies. The remote did not look at all like the garage door remotes that i have seen the insides of.

 

The car had the feature of built in programmable door opener that mimicked the FOB.
There was nothing to drop/damage.
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Oh that's pretty cool.
Just have to make sure not to accidentally drive it off a cliff and therefore drop the whole thing on the ground

That's a good idea though you dont have to carry around a stupid remote with you. I have so many remotes it's crazy. One fore each device, adds up quick. Lucky mine are all for in the house for stuff like TV's and the like.

But this makes me think. Why doesnt he keep the remote in the glove box and only pull it out when needed. If it was always inside the car, the farthest it could fall is about 16 inches or so onto the seat or carpet floor of the car.

Even though i was pretty sure i could get a replacement remote for all of my devices, i still logged all of the signal protocols and used a microcontroller to verify that i had the codes down correctly. Programming and reprogramming are easy today so i was about to use the same circuit for every device.
I still have the prototype built i'll have to take a pic or two and post here.

 

Just wire the transmit button permanently on, as soon as you get within the transmitter’s range of the door, it will open!

So what keeps the door from not opening as you drive off?

My remote is very old. My neighbor's is very new with a rolling code. Once or twice a year he lands on my code and my garage door opens.

Yup. First time it happened I was just perplexed. Second time around I realized that my neighbor down the street seemed to be pulling into his garage right at the very same moment. Fortunately changing the code wasn't as much of a hassle. But kind of annoying nonetheless. Maybe the newer stuff is better but at least a lot of the older garage door systems do tend to have issues with code uniqueness (or rather a lack thereof).