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noise XD-RF-5V rcv module

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colvstef

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I have cheap XD-RF-5V module.
It is possible to reduce output noise when is present in missing active signal ?


Thanks,
Stefan
 

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colvstef

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I found solution.
in my case solution is the soft not hardware.
I have 2 condition to starting receiving byte.
a. wait to 6msec. no noise
and
b. the first logic pulse is >200usec. and < 300usec.

because in lack of signal signal i have permanently noise.


Best regards,
Stefan

burst signal.jpg
magnify burst signal.jpg
noise.jpg
 

betwixt

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You did it the correct way. In most systems the transmitter is turned on without modulation for a few mS then a series of sync bytes are sent. The initial carrier produces the 'no noise' condition and also allows the receiver to adjust it's gain if it supports AGC. The sync bytes are there so if the receiver has an adaptive data slicer it can find the correct threshhold between '0' and '1' and also to allow your software to find the start bit in your data stream.

Brian.
 

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