ThePsuedoMonkey
XS400 Addict
OK, so was browsing around Amazon, ordering tools for my car, when a voltage indicator gauge caught my eye (the same one that I tried to attach to my bike last year). And I thought "yes, I would still like that information about my bike when I'm riding." Nothing I found really got me excited though, especially considering most were going for $40+. Then I started looking into DIY projects... and found only one that was simple and didn't require expensive, hard to find, or complex components.
Inspired by that find, I Googled an online circuit simulator and set to work with the specs of typical colored LEDs at my disposal. To me, there were only two acceptable outcomes: an easy to read and highly detailed model based on the number of LEDs illuminated, or a minimalist approach that spans the same voltage range and conveys the important information. I started with the OCD model, but my first attempts were less than impressive, since I was restricting myself to only resistors and LEDs. Retreating to the online radio shack, I picked out one of the zener diodes available and played with that. Eventually I ended up utilizing a little bit of each component to finesse my way toward the minimalist design. At it's most simple level, red=bad green=normal blue=good. It operates between 10V and 15V. The diagram is below, and the actual simulation can be used here.
What you need to know:
-Two zener diodes (Zener Voltage=8.4, Forward Voltage=1.1) in series with the source voltage, and polarity is reversed on the second diode.
-Three different LEDs (Forward Voltage= 2.1, 2.9, 3.1 respectively for red, green, blue) share a node with the zener diodes.
-LEDs are in series with resistors (100, 100, and 300 ohms respectively).
I did my best to make it simple enough for a novice to do in an hour with under $5 worth in materials. Now I just need to think about a tasteful way to mount this!
Inspired by that find, I Googled an online circuit simulator and set to work with the specs of typical colored LEDs at my disposal. To me, there were only two acceptable outcomes: an easy to read and highly detailed model based on the number of LEDs illuminated, or a minimalist approach that spans the same voltage range and conveys the important information. I started with the OCD model, but my first attempts were less than impressive, since I was restricting myself to only resistors and LEDs. Retreating to the online radio shack, I picked out one of the zener diodes available and played with that. Eventually I ended up utilizing a little bit of each component to finesse my way toward the minimalist design. At it's most simple level, red=bad green=normal blue=good. It operates between 10V and 15V. The diagram is below, and the actual simulation can be used here.
What you need to know:
-Two zener diodes (Zener Voltage=8.4, Forward Voltage=1.1) in series with the source voltage, and polarity is reversed on the second diode.
-Three different LEDs (Forward Voltage= 2.1, 2.9, 3.1 respectively for red, green, blue) share a node with the zener diodes.
-LEDs are in series with resistors (100, 100, and 300 ohms respectively).
I did my best to make it simple enough for a novice to do in an hour with under $5 worth in materials. Now I just need to think about a tasteful way to mount this!