what colour led should i use for roll your own vactrol?

[danwelsh]

Hi guys, so I just poplulated the afterlife and socketed the holes for the vactrol...I'm rolling my own and just wondering what colour led I should use and what size photocell(should the photocell be bigger around at the head than the led or smaller or same size?)....any help would be appreciated ....also can i experiment with them not shrink wrapped(following rock it before i box it) or will they not work with light getting through?

[juansolo]

I use 5mm red LEDs and Tayda LDRs.

[gtr2]

Make sure the LED is diffused.  Green or Red diffused is what I use.

Josh

[LaceSensor]

Yellow can be good too.
I beleive 3mm and 5mm work just as good

[danwelsh]

Make sure the LED is diffused.  Green or Red diffused is what I use.

Josh

josh, how do you know if its diffused? Is there a test i can do to find out?

edit......i googled it and i have all waterclear ones but i can sand them to make them diffused.

[gtr2]

There are two main types of LED's, diffused and waterclear.

This is a diffused

http://www.taydaelectronics.com/leds/led-3mm-red.html

This is a waterclear

http://www.taydaelectronics.com/leds/led-3mm-red-water-clear-ultra-bright.html

Josh

[danwelsh]

okay....so if the shell is red does that make it diffused?

[whitebread47]

okay....so if the shell is red does that make it diffused?

Yep.  If the casing is colored, it is diffused.  If it is clear, then it is waterclear.  Basically, if you can tell what color the LED is without looking at the package it came out of, it is a diffused.

I tend to like diffused better for everything because I have a ton of loose waterclears and no idea what color they are.  Sure, I could do the coin battery thing, but I'm on'ry! 

[billstein]

okay....so if the shell is red does that make it diffused?

Sure, I could do the coin battery thing, but I'm on'ry! 

I need to test the color of some LED's. what is the coin battery thing?

[DutchMF]

I have no idea what the "coin battery thing" is, but I test LEDs with my DMM on the diode-test setting. It gives off a small voltage, enough to light up the LED. Coincidentally, it tells you which lead to attach to 9V (anode) and to Ground/switch (cathode) too. If the LED lights up, the black lead is on the side that needs to go to Ground/switch. Keep one thing in mind: since a LED is a diode, it won't light up with voltage on the cathode, so you'll want to try it both ways around... 

Paul

[danwelsh]

awesome, thanks guys....i got it all done, now i wanna do johnpattons sensitivity mod to it 

[whitebread47]

I need to test the color of some LED's. what is the coin battery thing?

Use a 3v coin battery like those common in watches and the current doesn't burn the LED like a 9v would.

[davent]

okay....so if the shell is red does that make it diffused?

Yep.  If the casing is colored, it is diffused.  If it is clear, then it is waterclear.  Basically, if you can tell what color the LED is without looking at the package it came out of, it is a diffused.

I tend to like diffused better for everything because I have a ton of loose waterclears and no idea what color they are.  Sure, I could do the coin battery thing, but I'm on'ry!  

There are lots of LED's that are classified as 'clear tinted', the casing is coloured/tinted but they are not diffused, easy to see the difference.

http://www.digikey.ca/product-detail/en/LTL-1CHEE/160-1704-ND/566928

Is sanding the surface of a clear, sufficient to get it a diffused classification? i've done this with some super bright blues to get a less "pin-point" light source.

dave

[whitebread47]

There are lots of LED's that are classified as 'clear tinted', the casing is coloured/tinted but they are not diffused, easy to see the difference.

http://www.digikey.ca/product-detail/en/LTL-1CHEE/160-1704-ND/566928

Interesting, I'd never seen those.  I learn something new everyday 'round these parts.

[billstein]

I need to test the color of some LED's. what is the coin battery thing?

Use a 3v coin battery like those common in watches and the current doesn't burn the LED like a 9v would.

Ahhh... now I get it. I thought it was talking about a coin like a penny etc. Going to have to get one of those batteries.

Thanks for the answer.