Hi Joe,
IMHO the linear output of the RX is for testing purposes, you should
let it unused. The encoder/decoder pair is used as a key-and-lock, for
better reliability and security. Your solution using a pulse generator
at the TX side might do for a camera remote control - it can be less
safe than, say, a car alarm. A bandpass filter or a PLL checking the
frequency of the pulses on the receiver output should work even better
than a counter only.
The TX unit has limits for input voltage and frequency. If you do not
exceed them, no damage should take place.

BR from Ivan

"Joe" wrote in message hlink.net...
Hello to the group,

I just found this forum and hopefully, I can learn some more about
homebrewing stuff. I have been a hobbyist in electronics for a little over a
year now and recently received my element 2 tech license. Last year I built
an infrared transmitter and receiver pair to trigger my camera remotely
(about a 50 foot range). Since then, I have wanted to do the same thing with
RF. I have a tek465b oscilloscope and a dmm, and have built some of my own
test equipment (square wave signal generator, power supply, battery tester)
and lots of timer circuits with 555's and cd 4060s. Recently I have been
experimenting with audio and ultrasound with opamps. All of my projects are
battery operated.

I recently bought the Velleman RX 433 and TX 433 modules to try and remotely
control my camera. Each module has a 'data' pin, the receiver also has a
linear pin, which I am not sure how to use yet. I have been reading the data
sheets and app note on the velleman site and it shows something called a
HT12E being used to generate the data on the TX module and a HT12D to use
these modules for remote control. I googled for the HT12E and it says it is
a LSI encoder and you need the HT12D as the matching decoder (on the
receiver). Not being familiar with all the terminology yet, I am wondering
why I couldn't just generate a square wave to the data pin of the TX
module, and, then, at the receiver, use a divide down counter to make sure
enough pulses arrived, and then trigger my relay. Does anyone know if this
will work? or would it just be easier (and maybe more reliable) to use the
HT encoder and decoder?

I am asking because I am not familiar with the type of waveform or pulse
shape that the Holtek generates, and, I am not sure if I just want to try
pushing a 555 type square wave thru my TX unit and maybe end up letting the
smoke out.

Any suggestions or ideas are appreciated.

TIA,
Joe
KB1KVI