Audio Input with the Unidirectional Condenser Microphone Element: PLEASE HELP!

Jeffrey Maguire

Would the Unidirectional Condenser Microphone Element from Radio Shack be suitable for use as an audio input?
-Thank You,
Jeffrey


Unidirectional Condenser Microphone Element:

Mike Green

Audio input for what? This microphone is suitable as an audio input for many things. Some condenser elements need a preamp. Some need a power source. It all depends on what it's connected to. Also, which condenser element is this? Do you have a catalog number or link to a description?

Jeffrey Maguire

Mike, Thank you for your response. I am using the microphone for audio input in a schmitt trigger. You can find a schematic diagram for a schmitt trigger below:






I am using the Unidirectional Condenser Microphone element in place of the audio input on the diagram. A description of the product can be found at www.radioshack.com/product/index.jsp?productId=2103751&cp=&sr=1&origkw=Unidirectional+Microphone+Element&kw=unidirectional+microphone+element&parentPage=search
(just type in Unidirectional Condenser Microphone element in the search bar of the radioshack home page)

I'm not sure if this helps but I'm using the microphone+schmitt trigger & some programming w/ pbasic in order to measure frequency of sound from a violin.

Mike Green

Here is an introduction to this type of condenser microphone: en.wikipedia.org/wiki/Electret_microphone. If you'll look at the description, you'll see you need a resistor between the active terminal of the microphone (red lead) and the power supply (+5V) typically 2.2K or so. You may need a volume control on the input of the Schmitt trigger.

Bean

It should also be noted that you need a very quiet power supply to the 2.2K resistor (or whatever value you use). Any noise on the power supply will get coupled to the audio output.

I've used these in arrays to get a better signal-to-noise ratio. If you get good ones they are pretty decent microphones.

Bean.

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Phil Pilgrim (PhiPi)

Does anyone know what peak-to-peak output level to expect from these mics? This will help to determinine if Jeffrey needs any kind of pre-amp ahead of the Schmitt trigger.

-Phil