Simple Remote control

[Mike]

Ever see those fake fart machines?<p>Well, I want to build one of those.<p>Is there a simple way to build a transmitter/reciever that detects the push of a button?

[wd5gnr]

Have a look at http://www.wd5gnr.com/rfrem.htm. Quick and easy.

[Mike]

I'd rather build one plus not use pic/stamps.<p>Also, I do not want an IR transmitter since they need to be aimed right at the reciever, plus since this thing is something you hide, that wouldn't work.

[wd5gnr]

The article I mentioned doesn't use a PIC or a Stamp and it is RF, not IR. It is just a hack of a cheap piece of radio shack gear. I'm not sure where you got the idea it was PIC/Stamp/IR related.

[Mike]

oh never mind, that code is for computer control

[jwax]

How about a 555 timer in astable, running at say, 60 KHz, and a 567 phase locked loop to detect it? Very short range.

[wd5gnr]

The code that accompanies the article is for reading the remote from the PC. But the signal it produces is just a signal. You could use it to trigger anything. I just happen to be using it to trigger a PC serial port's handshaking line. In fact, I've used the same setup to trigger a relay and a Basic Stamp.

[Mike]

Thanks to all.<p>I think jwax's idea is what I'm going to go with, as you could buy a brand new one for only $15, so why buy something for $20, plus have to buy all the other parts.<p>Thanks a lot though.<p>About the 555/567, what do you mean by very short range? Do you think I'd get at least 10ft out of it?<p>Also, could somebody help me with creating a schematic? Finally, could somebody explain to me what Phase locked loop means?<p>Sorry about the stupid questions <p>Thanks again,
Mike

[jwax]

Here's a site explaning the 567 PLL.
http://www.du.edu/~etuttle/electron/elect12.htm
How much range? I'm not sure! The idea is the 555 generates a significantly strong oscillation at say 60 KHz. A nearby PLL is tuned to the 60 KHz signal, and "locks on" to it and signals lock-on with an output.
I'll look around for ultrasonic receivers/transmitters- How wide of a area do you want to cover? Line of sight is easy. Wide gets more difficult.
John

[Mike]

Well, line of sight is OK, as long as it can go through things. For example, if the thing is hidden in a jacket on the seat of the person, I want to be able to trigger it from the other side of a table through the jacket.<p>Would I just use the tone detector circuit on the page, tune it to 60khz, then attach a long wire as antenna to the input and the output to the trigger of the sound chip? Do I assume that the 567 will go logic high when it detects a signal on the input?<p>Finally, with the 555, do I just connect an antenna to the output also?<p>Thanks!

[jwax]

This doesn't utilize the PLL, but is a detector nonetheless, and apparently works! How much range and "penetration power", I don't know.
http://www.reconnsworld.com/ir_ultrason ... witch.html