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[15:01:14] <idiot2> hi
[15:14:53] <Lambda-Aurigae> iH
[15:39:30] <idiot2> :)
[16:21:18] <ColdKeyboard> Generally speaking, If I want to read the value from the electret mic via ADC, I need to amplify it via opamp before feeding it to the ADC?
[16:26:38] <Lambda-Aurigae> probably.
[16:27:35] <Lambda-Aurigae> probably want to do a bit of shift and amplify too as the mic is going to put out AC where the ADC is gonna need 0-5V DC or 0-refV DC anyhow.
[16:38:58] <idiot2> ColdKeyboard, you would need 10-100 times amplification and bias it to vref/2
[17:07:53] <ColdKeyboard> idiot2: Thanks. I'll try that now. :)
[18:43:53] <ColdKeyboard> Can someone suggest single rail, electrec microphone amplifier circuit?
[18:46:20] <Lambda-Aurigae> http://electronics.stackexchange.com/questions/57683/can-i-use-a-pnp-transistor-with-an-electret-microphone-to-get-an-non-inverting-o
[18:46:48] <Lambda-Aurigae> http://www.newcircuits.com/circuit.php?id=aum002
[18:46:52] <Lambda-Aurigae> how many more do you want?
[19:43:52] <idiot2> ColdKeyboard, hmm, 5V ?
[19:44:28] <idiot2> if cheap crap is sufficent then lm358 maybe
[19:46:07] <idiot2> otherwise, lmc6482 can do it
[19:48:35] <idiot2> ofc a single transistor is simplest... but the gain will vary
http://www.instructables.com/id/Pre-amp-to-electret-mic/
[19:49:34] <idiot2> Lambda-Aurigae, looks like we posted the same schematic ;>
[19:50:12] <Lambda-Aurigae> bet mine is older...yours is an instructable that was taken from something else...
[19:50:21] <idiot2> btw your second link contains opamp circuit that has bias at + input
[19:50:25] <idiot2> hehe
[19:50:40] <Lambda-Aurigae> yeah, so?
[19:50:48] <Lambda-Aurigae> I didn't draw it...just found it.
[19:51:03] <Lambda-Aurigae> looks ok for the most part..it should work...single rail opamp setup.
[19:51:12] <idiot2> so he could tie that to his virtual ground half reference , or just use 2x x k resistors
[19:51:37] <idiot2> and output capacitor can be omitted
[19:52:05] <idiot2> but i tihnk the input filtering network is fked up
[19:52:11] <Lambda-Aurigae> I'm not gonna draw up a custom circuit for him...sheesh...guy's gotta do some thinking on his own.
[19:52:15] <idiot2> 1k x 100nf sounds too high
[19:52:39] <idiot2> and that 100k feedback is just wrong
[19:53:03] <idiot2> but something like that will do
[19:54:36] <idiot2> the difficulty in opamp selection is the low voltage, 5V.. and output voltage swing
[19:54:48] <idiot2> but there are a few that can do it
[19:55:28] <Lambda-Aurigae> or just make a one transistor amplifier and be done with it.
[19:55:36] <Lambda-Aurigae> old school and all that.
[20:28:44] <ColdKeyboard> I used MCP6002 and modified this circuit
http://www.rason.org/Projects/hbmic/mikschem.gif and for now it seems to work :)
[21:46:45] <idiot2> http://www.ti.com/lit/ug/tidu765/tidu765.pdf
[21:47:06] <idiot2> Single-Supply,Electret Microphone Pre-AmplifierReference Design
[21:51:47] <osteri> Hi, I've been doing serial transfer with: AVR (UART) <--- rs232toUSB IC ---> /dev/ttyUSB0 -type of setup. Now I want to remove the extra IC (rs232toUSB) and replace its usage with LUFA. I have an ATmega32u4 (Leonardo). Should I choose the USB CDC firmware with LUFA for this kind of usage?
[21:55:04] <idiot2> hi
