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Two receivers at the same time

Posted: 01 Apr 2017, 09:41
by phermansson
Thinking about an idea... What about connecting two receivers at the same time, to the same input? One for 433MHz and one for 868MHz. Of course you cant just connect them, I was thinking of using diodes. Something like a 1N4148 or BAT85 on each receiver output and to the Mega's input pin. I know the signal will be lower, about 0,7 volts for the 4148 and 0,2 volts for the Bat85 but the Mega probably wont mind.
There will be collisions if both receivers receive at the same time, but that also happens if two transmitters transmit at the same time.
The question is if the diodes gonna disturb the signal edges? Is a 4148 fast enough?
Have anobody tried this before?

Re: Two receivers at the same time

Posted: 01 Apr 2017, 10:21
by Stuntteam
Wont work..

Re: Two receivers at the same time

Posted: 01 Apr 2017, 12:31
by phermansson
Why not? To connect two outputs to one input like this aint nothing new.

Re: Two receivers at the same time

Posted: 01 Apr 2017, 16:18
by Voyager
Both receivers will send pulses to the pin, the software will not know which module is providing pules

Re: Two receivers at the same time

Posted: 02 Apr 2017, 07:44
by phermansson
No it wont, but does it care?

Re: Two receivers at the same time

Posted: 02 Apr 2017, 11:32
by phermansson
Ok, I made some test now that didn't work. But it is the diode that makes trouble. Too bad I don't have a BAT85 to test with, just 1N4148.
I connected one receiver directly to the Mega, it works. I connect the receiver via an 1N4148, doesn't work. Hmm.

Re: Two receivers at the same time

Posted: 02 Apr 2017, 19:39
by Stuntteam
Two reicever modules then can send signals at the exaxct same time..
receiver 1: 10101010
receiver 2: 01010101
arduino sees: 11111111 which actually means that the pin goes high and stays high until both modules are done receiving.
Thus there is no way to see who is receiving what and what the signal actually was..
There are other solutions and we are working on that.

Re: Two receivers at the same time

Posted: 08 Apr 2017, 06:46
by phermansson
Mmm thats true. And the noise from the second receiver will interrupt the signal from the first receiver, therefor it wont work.