- Wed Jun 28, 2017 5:11 pm
#195327
I am working with a pretty simple circuit and riding the struggle bus. I have the Electret Microphone Breakout (https://www.sparkfun.com/products/12758) and I am trying to get it to play out of the Thin Speaker (https://www.sparkfun.com/products/10722). All I am hearing is a periodic click out of the speaker.
First, here is my setup (sorry for the ASCII art):
I also verified that the NPN transistor collector is connected to the negative side of the speaker and the emitter connected to ground. From looking around online, this looked like a way to drive the speaker since the op amp on the breakout cannot supply the full quarter watt.
I'm pretty sure there is a glaring error is what I am doing, but I cannot see it. I'm just trying to start with the sound from the microphone playing out of the speaker.
Any help would be much appreciated. Thank you!
First, here is my setup (sorry for the ASCII art):
Code: Select all
I hooked a quick ADC -> 8-bit digital output from the microphone breakout board, and verified with a logic analyzer that it is getting full precision (0 to 5V) out of the microphone when there are loud noises. Originally I put it through an additional inverting op amp, but this looks unnecessary. +5V
^
|
-----------
| Speaker |
+5V -----------
^ |
| v
------- ----------
| Mic |---> 250 Ohm --> | 2N3904 |
------- ----------
| |
v v
GND GND
I also verified that the NPN transistor collector is connected to the negative side of the speaker and the emitter connected to ground. From looking around online, this looked like a way to drive the speaker since the op amp on the breakout cannot supply the full quarter watt.
I'm pretty sure there is a glaring error is what I am doing, but I cannot see it. I'm just trying to start with the sound from the microphone playing out of the speaker.
Any help would be much appreciated. Thank you!