Sunday, October 9, 2011
It Came From Radio Shack!!! #1 - Line Mixer
Welcome to my new portion of the blog, It Came From Radio Shack!!!. Being the paranoid type, I tend to not want to order parts online for my personal projects. So I occasionally (constantly actually) peruse the component bins at the Radio Shack in the mall. I've build many projects from the parts I get there, and I thought I'd share them with you.
As a circuit bender, I need a little mixer for recording and playing live, but I really don't need all the fancy shmancy functions of the one's I see online. So I found this schematic online and thought I'll modify it for the easily accessible parts I can find at Radio Shack. The modifications are replacing the TLO72 dual op-amp with a TLO82 dual op-amp (which are virtually the same IC), the 2.2uF cap at C7 is now a 10uF, and the 8.2kΩ resistor limiting the current to the LED is now a 220Ω.
Sorry this doesn't have a real step by step process. I finished the project before I thought of this ongoing article. For my next project (still figuring that one out) I'll take pictures of the entire project, from breadboarding to laying out the enclosure.
This mixer is perfect for mixing different bent devices, but if your bent device has an extremely hot (loud) output, put a volume lowering resistor in line with the jack. If the output is too loud it will bypass the volume control in the mixer and be very very loud. I learned about this from plugging my speak and spell into it and having it be louder than toys that were cranked up all the way even when the S&S was turned all the way down (on all tracks). If you want to know how to adjust the volume of your bent toys, check out this article by Casperelectronics.
Next time on It Came From Radio Shack!!!: Resistor Box