LDR/LED testing

[Kipper4]

I would like to know more about testing roll your own vactrols.
How do i wire a test rig please
Whats involved ?
How do you do it?
Thanks
Rich

[The French connection]

came across that this morning...maybe it can help...or not.
http://home.online.nl/fvrijswijk/guitar_electronics_diy/optocouplers_and_measurements/optocouplers_and_measurements.htm

[deadastronaut]

camera film canister  (which i doubt anyone has these days) ...2 tiny holes. poke the ldr inside put lid on..

just thinking aloud..

[Ajay]

Although I'm not sure what it is exactly that you'd like to test, I sort of demonstrated a LED/LDR combo to my 8 year old son last week (allowing him to do the resistance measurement and turning the pot for the circuit I made): I picked a bright amber led, an Light Dependent Resistor, a transistor and some heat shrink. I 'drove' the led with a basic bc547, using a 1Meg pot for the base current and putting the LED in series with the collector. With that I was able to change the LDR's resistor between 5Megs and 10K, which is enough for my appication.
I kinda like DA's idea though and in case you don't have film cannister, you could give an old ball point pen a second use by cutting it and putting the parts inside (and maybe use a little tape for making it more ambient/daylight sensitive.
Once you'd have a proper combination, you could opt for doing the heat shrink trick; if one layer is not enough, two or three definitely will  

[Kipper4]

thanks guys
I'm trying to test the ldr resistance so i can get somewhere in the ballpark of the vactrols.
I would also like anytips on series or parrallel resistors and where they go, to compensate for over or under resistance of the combo.
I read somewhere in my research that homemade vactrols cannot compete with shop bought in there characheristics because of there make up but unless i'm forced to i'll use homemades .
ideally i'd like to make something that would be useful to put in a mutron iii, madbean naughtilus build that would work well.
and or something i can use in an oscillator for my own autowah design combo. I was thinking of using the tremelous lune oscillator.
thanks

also how much differant are the differant coloured superbright leds and diffused leds
what have you tried what works for you?
I read somewhere superbright greens should work well. I'm currently using superbright yellows. after it worked well in Dead Astronaughts Light wah

[PRR]

Simple cheap RED LEDs always worked great for me.

With the short spacing you usually have PLENTY of light to smack the photoresistor, even if it seems the "wrong" color. The factory jobs are specced for 16mA, but in actual builds I never saw near that much happening. 4mA bottomed-out, 0.1mA or less mid-range.

[Kipper4]

Thanks Paul appreciate the input.