Using the analog input of the Arduino Uno, can an audio signal say 10Khz that is amplitude modulated with 0's and 1's with a short 8 bit code say 11110000 be demodulated/detected with the Arduino analog input and retrieve this code to be verified that it is 11110000?
The reason for using the analog input is that the input signal is weak in the range of 100 milli volt peak to peak.
The idea is to make use of Arduino as far as possible for all the "heavy lifting" with minimal external components.
I will write my own code, but does not fully know the limitations of Arduino and what is practical or not and if someone can just point me in the right direction please?
Do you mean that the data part is added to a carrier wave ? or is it just the data signal ? At 100hz the Arduino can receive almost anything, but if the signal is weak, i suggest you do amplify it first.
Deva_Rishi:
Do you mean that the data part is added to a carrier wave ? or is it just the data signal ? At 100hz the Arduino can receive almost anything, but if the signal is weak, i suggest you do amplify it first.
Yes data is added to the 10khz signal, and the signal can be amplified by opamp first, is it hard for the Arduino to receive data faster then 100Hz?
Maybe I can just use a signal diode 1N914 after being amplified and keep the modulation rate at 100Hz, can you give me an example how to start the decoding of the data part please?
ocnuybear:
The reason for using the analog input is that the input signal is weak in the range of 100 milli volt peak to peak
How much variation is there? Plus or minus how much?
As far as decoding, you could do it in software but the practical analog sampling rate is normally not that high (your 10kHz).
If you add an AM detector as you have proposed, the "decoding" is just reading bits from the input pin. But, you haven't suggested any clocking or framing methods. If you want examples of AM signal decoding, you could use the RadioHead OOK implementation as a guide. I think you've gotten too far ahead of yourself here. You need to think more about the design and protocol before you start coding (or asking for code).
Actually, you contradict yourself, suggesting the "amplifier and diode" after previously ruling out something like a comparator that would amplify and convert the signal to digital voltage levels.
aarg:
How much variation is there? Plus or minus how much?
There is very little signal variation it gets a signal from a standard IR diode, and no I don't have the fancy Vishay IR diode package that does all the amplification & decoding.
aarg:
Actually, you contradict yourself, suggesting the "amplifier and diode" after previously ruling out something like a comparator that would amplify and convert the signal to digital voltage levels.
You are right, but I need to ask the right question to get the right answer and have very little experience with Arduino.
Currently have an existing IR tx using 555 @ 10Khz, receiver is an LF356 op-amp feeding into a 567 tone decoder @ 10Khz, trying to built a "IR Gun" tht can only shoot for 100ms after trigger is fired, this beam is then narrowed via 60cm pvc pipe to keep the spot size down, the 567 tone decoder then feeds an 100ms one shot timer 55 that triggers another 555 mono-stable that adjusts the duty cycle for a servo motor turning the target flat for a couple of settings - this setup gives me 8 meters tested in outside daylight, can this be done with the Arduino with much less components?
The idea is rather then detecting 10khz with the Arduino that seems complicated to rather wait for a simple code to trigger the servo.
What is the best educated guess, will the Arduino be able to half the components used compared to the analog version?