I missed when things flipped from non-invert, to invert and back again so the input resistor on the inverting version was needed.
C3 should be flipped around (or better yet, use bi-polar caps on all the inputs).
I'm not following; with R7 and R8 in the circuit, what's the need for R1 and R2?
Look at nigelwright7557's post a few posts up for the reason behind c3 being in the configuration that it is. I may use bi-polar caps for those before it's over anyways, but I have a lot of polarized smd caps that I want to use up so I don't know yet.
I tried the circuit without R1 and R2 and it lost over half of it's volume. I can't remove them. I don't know about R7 and R8. I haven't tried removing them yet.
R1.,2,7 and 8 form a mixing circuit.
If you take them out you could end up with the mp3 player shorting out the guitar opamp output or vice versa.
The circuit os ok as it is.
If you take them out you could end up with the mp3 player shorting out the guitar opamp output or vice versa.
The circuit os ok as it is.
Here is a pic of my amp almost completed. It works great and sounds really good. I made it so that a 9v battery will sit right down in there and fit perfectly in the 2"x3" enclosure. Thanks for all the help and advice. I will post some completed pics when I get the last stereo jack that I am missing and clean some of the flux off the board.
Here is the final schematic.
Here is the final schematic.
An externally hosted image should be here but it was not working when we last tested it.
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Here is a pic of the finished product. It works beautifully! The wire plugs into the the guitar and the headphones and mp3 player go into the 3.5mm sockets on the side.
An externally hosted image should be here but it was not working when we last tested it.
Here is a pic of the finished product. It works beautifully! The wire plugs into the the guitar and the headphones and mp3 player go into the 3.5mm sockets on the side.
An externally hosted image should be here but it was not working when we last tested it.
Its nice when something comes together and works well.
Whats your next project ?
Its nice when something comes together and works well.
Whats your next project ?
I am in the process of designing a midi light box for electronic drums. It is based around the Arduino and basically flashes a light each time a drum is struck. These can be mains lighting or LEDs inside of each drum or whatever else you want to light up. The hardware is finished and I have teamed up with a programmer to do the software end of it. The final product will have a 16x2 lcd display and a five button input for changing the color, duration and midi note.
Eventually we will taylor it to work with any midi instrument. Here is a pic of the first prototype that I made.
An externally hosted image should be here but it was not working when we last tested it.
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