Roll you own LED/LDR

[hammerheadmusicman]

Was going to have a go at rolling my own LED/LDR for a Demeter Tremulator i'm building, any suggestions on what kind of LED i should use?ni have loaeds of 3mm ultrabrights in lots of colours, and some normal 5mm's kicking around too.

Thanks

George

[trickpony]

I would suggest socketing both led and ldr and trying combos...for my trem I ended up not using superbrights as I couldnt dim it enough for the ldr....ended up using cheapo non clear 3mm..

[hammerheadmusicman]

yeah, i plugged it all in and the 'rate' LED was constantly on, i'm assuming that it's because the Led inside was just too bright!

i'll try a cheapo!

thanks

George

[Haberdasher]

I've always had pretty good luck using 5mm diffused yellow.  dirt cheap at tayda and they also stock some photocells.

[GermanCdn]

In trems I've used ultrabright white 5 mm in heat shrink tubing with a Tayda photocell, mostly because I don't use white leds for indicators.  Works pretty well, although you can't dial the intensity the way you'd normally like to.

[hammerheadmusicman]

i don't have 5mm ultrabright whites, i've started using only 3mm ultrabrights, but i do have 5mm diffused yellow, from an accidental order. so ill give that a try, thanks!


George

[LaceSensor]

Always had good joy with diffuse yellow or green with standard 5mm 1M ldr but your mileage may vary

[jaidee]

If you want to get really scientific about it, check the specs of the LDR and see what wavelength it is responsive to and match an appropriate LED; most big suppliers (e.g. Mouser or Farnell) have parts search engines which allow for LEDs to be selected by wavelength.

My experience is that diffused green is usually about right.

As ever, though, there is no beating trial and error!