mstechca
New Member
Ron, A microcontroller can be a solution, BUT it must be programmed. If bananasiong is willing to spend time programming it correctly, then it may be no problem.Ron H said:Spend some time learning to program it. As we have told you, it is the answer to your noise problem. You could spend months farting around with different kinds of comparators (a comparator is not an op amp) and filtering schemes.
I am detecting remote signals myself, and all I am doing is making a simple PLL using a 555 timer, 2 XOR gates, and 2 NAND gates.
I agree 100%. If the frequency is even slightly off, and the bandwidth of the transmitter is not high enough, the range will also drop, and the signal quality will be poorer.Also, if you get your transmit and receive frequencies to match, you will get better noise rejection.
One way you can do that is to picture the project in your head, and pretend you are the electricity flowing through it.If you want to learn from a project, one of the most important things you can do is understand why it doesn't work the way you think it should.
A software filter, very interesting :wink:if there's a spurious short '0' do as already advised and software filter it - basically don't respond unless the '0' lasts more than a certain time.
BUT, you must understand that if you intend to use the same microcontroller for another application at the same time, you must consider the rom space required for the filter, and subtract that from the total rom space.
Nigel does have a point. What he is introducing is what is called a "timeout". Assuming that "no signal" or an invalid signal produces a binary 0, If the result is 0 long enough, then you can make the microcontroller go to an error routine.i don't think it can be used perfectly if the receiver gives a short off when there is no signal. because my microcontroller keeps detecting the output of the receiver, if there is a '0', it will response to it and turn.
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if there's a spurious short '0' do as already advised and software filter it - basically don't respond unless the '0' lasts more than a certain time.
BUT
this will only work if your transmitter transmits a continuous "1" bit.
If your transmitter transmits a certain tone as a logic high, a PLL should be used to detect the signal.
and continuously transmitting a "1" can waste power.