LED lit gauges

[volksdragon]

Originally Posted by Supa Ninja

It's been a year and a minute since I updated you ninjas on my lil LED r&d project. Things are happening again, so stand by and I'll have a big update! BTW for a year I have been running the blue LEDs in my 914, still works great, just wish they were a little brighter.

any other colour would be brighter

blue l.e.d. s give the least luminesence (spelling?)
red yellow and white are the 3 best

[oasis]

Originally Posted by volksdragon

any other colour would be brighter

blue l.e.d. s give the least luminesence (spelling?)
red yellow and white are the 3 best

Is that because blue light has a shorter wave length? ... or because of the nature of LED's themselves?

The reason I ask is because I am starting to do some serious mulling over what I want to do with my 1302 with respect to gauges and stereo. I am considering LED's but at this point, I have neither locked in on them nor eliminated them from consideration.

[Supa Ninja]

OK here is where I am at. I sat down and reverse engineered a few of the circuits that I had put together last year. I figured out what I was doing and made the finishing touches and now I am back on track. I even went so far as stuffing red LEDs into sockets, putting them into gauges, pluging them into the current limiter circuit, and pluging that into the dimmer switch. Definitely almost a real world test, best I can do since the 1302 isn't a runner.
My results- the current limiter worked flawlessly, I turned the know on the dimmer switch all the way CCW and they still were getting a steady 25mA. Conclussion is from 2-16.5vdc tested a constant current, theoretically it should be able to sustain around 50vdc with no ill effects. I wish I had dimmer capability but that will take some more R&Ding, also it's not nessacerily(?) plug and play cause different LEDs have different voltage drops and that messes with final value of R3. The final number of LEDs is also a factor of output current.
I took some pics of the final circuit layout and what the circuit board looks like. As far as how it the final results, I wish they were brighter. I'm putting running the LEDs at 25mA and they should be 20mA, but they can take up to 30mA so I don't want to turn that up anymore. I could take the gauges apart paint the inside white. The last option is to get brighter LEDs, all I have to do change R3 to compensate the different load.
If there is a interest in the current limiter circuit, I have enough extra parts to build a few, but I'll need a small donation .

[volksdragon]

Originally Posted by oasis

Is that because blue light has a shorter wave length? ... or because of the nature of LED's themselves?

The reason I ask is because I am starting to do some serious mulling over what I want to do with my 1302 with respect to gauges and stereo. I am considering LED's but at this point, I have neither locked in on them nor eliminated them from consideration.

it's from experiance

i used to work at a computer modding company. we did all kinds of stuff with l.e.d's and it just worked out that blue always seemed to be the dimest of all.

these where all high mcd l.e.d's so i'm sure it has to do with wave lenghts.

i'm thinking of doing yellow in my gauges since it shows up the brightest at night.