Rick’s Awesome Blog

This idea is pretty simple. The idea of wearable electronics is just awesome to me. I’ve already built the LED belt. I still have about 90 of those surface mount LEDs left over and I need something to do with them. This idea involves a wearable tie that has a VU meter built in. I had this idea when I saw a VU meter t-shirt on thinkgeek. I want to put a few LEDs into a tie to make a vertical line. Towards the top of the tie I can put a small microphone. This mic can go through an amplifier and into a micro controller. I might also need an analog to digital converter. I’m not really sure how to do all of this yet. I’ll have to start Googling around for schematics.

4/10/08

I started this project today. I found some instructions for creating a simple VU meter over at Instructables. I was able to locate the LM3914N IC at a local store called the Circuit Specialists. It cost me about $9 but it works. They’re probably the only place I’d be able to find this part without having to order it online and wait. I’d like to get this project done on time for graduation so I might be able to merge these two projects together.

I followed the schematic on that Instructable and lo and behold, it works. The only thing is I didn’t have a 1uF capacitor lying around. I might be able to get one at school tomorrow. I had to use a 4.7uF instead. The circuit works, although I have to crank up the volume on my iPod in order to get all of the LEDs working. I’m not sure why yet. It could be the capacitor that I used. I’ll find out once I get the right one. I’m going to go over the datasheet for the IC and see if there’s anything I can do about this. Maybe it’s my input voltage…

One other thing is that I need to get this circuit working with a small microphone.  I’m guessing that since my iPod has to be cranked up in order to get the LEDs going, a microphone by itself with do nothing.  I will probably need an amplifier of some sort.