Car keychain remote question, techie question moreso?

Question

What is the maximum distance those types of signalers work and what type of wave to they transmit, infrared? I have an idea for a pay-at-the-pump type swipe device but it would be a click button type thing instead, but wondering if that technology would allow for just one receiver within the station building instead of receivers at each pump as is with current 'swipe' type pay keychain fobs

so the question is how does that car alarm tech work - because current car keyfobs are not "random" enough (ex. one may find their remote operates another car, although the key probably wouldn't) the encryption would have to be more specific than current car alarm type

and what is the maximum distance those types of receiver systems can cover? and what about obstructions/reception issues>

thanks

Answer 1

They send a radio frequency. Max distance depends on circuit design, battery strength, intervening obstacles, and so on. Anywhere from 15 to 30 feet.