Tres Bright 5mm LED's for Guitar Effects Pedal?

[Leo_Loves Light]

Hi guys,

I know this is a forum dedicated to torches and whatnot but after a fair bit of googling, a lot of relevant threads were popping up here so I thought I'd ask y'all as there seems to be a lot of knowledge, wisdom and expertise here.

1) Could you tell me some examples of very bright 5mm LED's that would be fine to run off of the Volts / Amps inside a guitar effect pedal?

2) I've been advised to buy a couple of resistors ranging from circa 400ohm to 1.5Kohm to try out (to affect the brightness if it's too bright) - but I don't know whether to buy resistors rated at 1/4w or 1/2w or whatever.....?!

3) Where would be a good place in the UK to buy the above LED's + Resistors and wire to hook it up with? - there's a site called RapidOnline in the UK who seem fairly good although they only sell wire in rolls of like 10m and I only want a little bit...


thank you all very much in advance!

 

[Biker Bear]

Are you looking for white LEDs, or colored ones?

LEDs have a characteristic known as "forward voltage" or Vf; to determine the resistor you need to limit the current through the LED, you use Ohm's Law. In this case, (Vsupply-Vf)/(Current in Amps)=(Resistance in Ohms). For example, if your pedal uses a 6v DC power supply and you have an LED with a 3.3 Vf that needs 40 milliamps: (6v-3.3v)/0.04A=67.5 ohms. If you want a lower drive current for less brightness - substitute that in the equation to get the appropriate resistance.

You likely won't find that exact value, but you likely can come close. As for wattage, Watts=Amps x Volts; in this case, 0.24w=0.04A x (6v-3.3v) - or about 1/10th of a watt, so 1/4 watt resistors would be fine.

Given that we don't know what brightness you want - you may have to experiment a bit. Note that different color LEDs have different forward voltages, so if you want a variety - you'll have to account for that.