SparkFun Forums

[ajajack]

I have purchased a RF Link - 4800bps - 434MHz (SKU#: WRL-07815) and want to use it without microcontrollers. Someone was telling me that a 555 timer would do the trick if I had one with the transmitter and one with the receiver. Basically I want to see if I can hit a switch on the transmitter circut and then light an LED up on the receiver circut. That you for your help.

[riden]

Take a look at a Holtek encoder/decoder pair or one of the encoder and decoders from Rentron. http://www.rentron.com/remote_control/Holtek.htm#R8P

[ajajack]

Does anybody else carry something like this? Also, is there a way to do this with the 555 timer because I already have that?

[riden]

Digikey carries the Holtek line, but I'd try the 8 pin chipsets that Rentron have. Their support is very good and they stand behind their products. As far as using a 555 goes, there is a thread that discusses it. It COULD be done, but you cant' get much simpler than these encoders/decoders. There are considerations for your transmitter/receiver pairs (duty cycle, data balancing, etc.). You just can't turn the transmitter on and have the receiver switch on. Check the threads on this forum and you will see what I mean. Do yourself a favor, pick up a encoder/decoder pair, and be up and running in a few minutes. Check out this schematic for a 4 channel controller.

[RonnyM]

You could use a 555 as your tone source, but you might need a 567 as a tone decoder. Noise from the receiver will also trigger these little guys if you do not design carefully.
Ron

[Philba]

You might be able to use it for the transmitter (ala the tone source comment above) but how are you going to figure it out on the receiver side?

A suggestion, don't try to pound a square peg into a round hole. the holtek chips are really pretty cheap and work quite well with few additional components.