CLR for 2.2 mm LED

[cruisemates]

what size resistor do I use for a 2.2 mm (tiny) LED?

Nevermind - I got it 2.2k - but I have something else making it not work. thx anyway.

[vibratoking]

What is the supply?

[Bob S]

Try this :--
http://led.linear1.org/1led.wiz

[cruisemates]

Thx - I got it to work, it's 2.2k

but I have another circuit problem.
I have a small PCB for a foot switch that has a space for a CLR...

one leg of that CLR attaches to the LED - and that's all I have.

So, I put in a 2.2 CLR and a 2.1mm red LED in the PCB attaching the CLR to + of the LED. The neg lead from the LED I ran to ground on the PCB - that should work, right?

The circuit works, I have sound, just no LED.

[ampgeek]

Current limiting resistors for LEDs can go on either the + or - side of the LED depending on the circuit configuration.

What is on the other, non LED side of the CLR in your configuration?

If it is +, it should go to the + side of the LED. If it is ground, it should go to the - side of the LED.

Or...just switch the LED around to see if it works!

Good luck,
Dave O.

[cruisemates]

Thank you all for your help. I tried going +9 - |>| - CLR - GRND. but it just never worked for me. Not sure why.

Now I am wondering.....

I see another way to wire this PCB so the CLR comes before the LED but that would mean bringing +9 right to the foot switch PCB. Does anyone think that could cause problems like oscillation?

[eniam rognab]

i dont know what the appeal of those switch PCBs are... not trying to be rude or judgmental, i just don't think it's that hard to wire up a 3P2T switch... i'll attach a drawing i made to remind myself how to hook it all up, i prefer this method because it grounds out the effect input when the effect is turned off. YMMV, different strokes for different folks.

if anything doesn't make sense feel free to ask me anytime! LED cathode is lifted from ground and whatever resistor is tied to the anode-then to the power supply, works great for me!!

have fun!
neal

[ampgeek]

If that is how you actually have it wired, and the +9v is going to the anode of your LED.....the LED is shot.

There is no other reason that I can see why it shouldn't light up.

Note the flat spot at the edge of the LED dome on the cathode side in the attached.

Cheers,
Dave O.

[eniam rognab]

are you talking to me Dave O.? cuz i always get them confused....

take a left, right?

i usually look inside the LED and the biggest of the elements inside is the groundy one, small electrode the + one....

meh, i should just stay out of this.... never used a PCB switch, or had problems with LEDs not lighting up....

[ampgeek]

LOL! Right...err...left..aww hell...I am ambidextrous and can't tell!!

I was telling Cruisemate that his bulb should be lighting up if it was wired in the way that he described it.

Cheers,
Dave O.

[davent]

No one size fits all for clr's, with a 9v supply i've used from 470r to 47k to get a suitable brightness from the various led's i have.

I plug them into a resistor switch box 24 positions fron 510 to 18k, to determine what individuals need.

[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... G_4614.jpg[/img]
[IMG:800:600]http://i216.photobucket.com/albums/cc30 ... G_4619.jpg[/img]

dave