"OK1SIP" wrote in message
om...
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
Hi BR,
Thank you for the info. Today I connected the transmitter data pin to my
square wave generator with a 1Khz square wave (at 3V peak) and I could see
it on the receiver output pins, both the linear and digital pins on the
receiver output pretty much the same signal. The only thing I was confused
about is that, when I first switch the receiver on, the digital output is
quiet (it goes to 5volts at first and then drops to and stays at zero
volts). Once I transmit the square wave to it and turn the transmitter off,
the digital output is very noisy (low frequency, I think) and never settles
back to zero. The linear line comes up to about 2 volts on power up, shows a
pretty good square wave when the transmitter is on and then goes back to the
2 volt level when the transmitter is turned off and stays much quieter.
I can probly filter out the noise on the digital line, or capacitively
couple the linear line to get rid of the dc, but I still need to study this
more. The range was amazing! I measured about 60 feet (~20meters) and the
signal was still strong. This was with the receiver in a building and the
transmitter outside. I can still get more range out of it I am sure, so I
will be testing that also.
I have never worked with phase lock loops before, but I do have a few in my
cmos collection, along with the data sheets. Do you know of any links I can
visit to see some applications of the cd4046B PLL?
Thanks,
Joe
KB1KVI
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