Hello,
Sorry if this is already covered to death but the SF forum search was AWOL. A friend of mine has some remote property that hunters and farmers use all the time to get to other remote areas. The problem is they miss the crossroads and turn-offs at night and don’t see the posted signs, get lost and wind up waking him up asking directions. So he asked if I could build him some solar LED lighting for the signs so the drivers wouldn’t blow past them.
One of the problems is the hunters use the route at all hours of the morning so it has to be lit up all night, which would be a rather large expensive setup, especially considering the crappy no-sun weather they often get. So my idea is to use motion sensors to turn the LED’s on at the stop signs so the motorists would notice them. That way we could use a much smaller panel and battery since the LED’s only need to run for a couple of minutes at a time a few times a night.
So I figured for the lights to go on 10 seconds or so before the drivers past them. To give a driver going 60 MPH on a dirt road time to notice the lit up road sign in the distance, I need the sensor to be 1,000 or so feet from the sign.
So what’s the cool RF setup for: 1000’, good reception, line of sight except for some shrubs and cactus and brush? Is it out there? I’d need to run the senors on a small solar system and just check every second and sleep the rest of the time or something. Sensors transmit 1 when they detect a car. Main controller turns on the LED’s for a couple minutes. I don’t need digital networking, just one binary number 0=no car, 1=car. I was going to use PIR sensors to pickup the cars going by. Would ultra-sonic range sensors be better? (I’ve never used them).
I’ve played with the Nordic fob but I don’t think it has the distance I need. Any ideas? I think Future Electronics talked about some 3 mile range radios in their new products announcement last week. Anyone played with those?
Thanks!