sound frequency sensor - audio frequency sensor

mnastasi

Team
I would like to list for a frequency of sound. this sensor looks good. http://www.embsysstores.com/sound-frequency-sensor.html
does anyone know how to use it with Prop C?
your help is appreciated.
thanks , Mark

Mike Green

There's not a lot of information available from your link. The sensor has an amplifier that feeds into a fixed frequency tone detector that's manually set (via a potentiometer). The tone detector outputs a 5V logic signal ... +5V if the tone is present and 0V if the tone is not present. The Propeller uses 3.3V logic signals. You can connect a Propeller I/O pin to the sensor output through a 3.3K or larger resistor to protect the I/O pin. With Prop C, you'd use the input(pin) function to check whether the I/O pin is high (1) or low (0). Check the Prop C documentation for details.

kwinn

Then again, you can do the same thing with a propeller chip, microphone, and an op amp. Amplify the signal and input it to one of the propeller pins and use the propeller to measure the frequency, then have the propeller do whatever you want if it is in the range you specify.

Beau Schwabe

Heck, you can even leave out the Op-Amp and let a software implemented Sigma Delta ADC do it .... Even a PIC16F54 can implement enough of a Sigma-Delta ADC to do the job without any pre-amplification. That's how I did it here ==> VU Meter

jmg

mnastasi wrote: »

I would like to list for a frequency of sound. this sensor looks good. http://www.embsysstores.com/sound-frequency-sensor.html
does anyone know how to use it with Prop C?

At a guess that uses a NE567
eg http://www.dl2lto.de/gif/HB_ZB_1.gif

That gives a static on/off type signal, that should be easy to use in Prop C - just test the pin level.
A series R may be needed for 5V -3v3 handling.

What specific frequency do you want to listen for, and what duration and stability and noise floor does that have ?