Re: one channel radio frequency help

On Apr 3, 6:49 am, "robot guy" <huntin4je...@xxxxxxxxx> wrote:
I could use some input on this subject. A while ago I used infared
led's hooked up to a 555 to flash at a certain speed, I can't remember
what speed it was but I then had some special little divice that when
it saw an infared flashing at one specific givin speed it would either
close a switch completing the circuit, I can't quite remember how I
wired it but any way I'd like to do the same with a radio. What I want
it to do is turn on and led first than move on to turning on ovens,
unlocking cars etc...
I have a good idea how to do it, just take a transmiter and pulse it
at a certain speed with a 555 but how do I get my reciever to only
regonize that certain speed, a filter, a tone detector? I could really
use some input or websites to look at.

I did something like this once to unlock my car and house by just
walking up to them. It used a PIC for the sending unit banging out a
very short code pulse about once a second and then going back to
sleep.

It worked great 'on the bench' and totally failed in any bright
daylight.

Luhan
http://mondo-technology.com

.

Relevant Pages

  • Re: one channel radio frequency help
    ... led's hooked up to a 555 to flash at a certain speed, ... what speed it was but I then had some special little divice that when ... it to do is turn on and led first than move on to turning on ovens, ... unlocking cars etc... ...
    (sci.electronics.design)
  • one channel radio frequency help
    ... led's hooked up to a 555 to flash at a certain speed, ... it to do is turn on and led first than move on to turning on ovens, ... unlocking cars etc... ...
    (sci.electronics.design)
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