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wiring a model for lighting

This may be a stupid question, but I haven't wired anything more complicated than a lamp socket replacement in years...

Suppose you have installed a pair of screw terminals inside a model section, which lead to the power source elsewhere.

What you want to do is attach two simple series of LEDs (just the diodes and resistors) to those terminals, as well as a small circuit board which drives a timer to make a couple of separate LEDs blink.

My question is this: do any of those three circuits affect the others when they "feed" off of the same pair of posts, which come directly from the power supply?

To put it another way: assuming a 12v DC supply, would each of the three circuits get the full 12v? Or am I not making any sense?

Thanks in advance!

Reply to
Casey Tompkins
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If the circuits are parallel it should.

Reply to
chris

Older LEDs need only 3 cells (4.5 Vdc.) Newer LEDs require only 1.7 Vdc (2 cells). Any overvoltage will fry them. You can actually hear one go POP with 12 V.

Save yourself a lot of installation, wiring and barrery problems by going to the Dollar Store and look for LED type devices (flashlights, reading lights, keychain tokens) and toys. Some small but very bright pinhead LEDs embedded in a brooch have chaser LEDs. Also look for toy battery powered noise makers (bombs, machine gun, rocket noises) to enhance your model. For a buck you get the complete LED, battery and housing.

Reply to
PaPaPeng

If I understand the terminology, yes they are. The only place the three circuits contact each other are at the screw terminals.

1 2 3 (circuits) ^ ^ ^ | | | term>If the circuits are parallel it should.
Reply to
Casey Tompkins

I think he's got the right idea using a resistor in series with the LED. With the right resistor value you can use an LED with just about any voltage. The fun part is figuring the value of the resistor. Holler if you need help.

Doug Wagner

Reply to
Doug Wagner

Thanks Doug, that's what I was given to understand. It doesn't matter what the current supply is, as long as you cut it down to size.

I was, by the way, going nuts trying to figure out just how I was supposed to figure the milliamps coming from a 9v battery, until it hit me that didn't matter. :)

12v was just an example, although I may have to go with that if I want to use the new cold-cathode tubes to illuminate the warp nacelles.

On the other hand, there's always 9v. IIRC, that's enough if you want to use lightsheet, or an equivalent.

Which reminds me, for those who have done a Star Trek starship with LEDs: what brightness do you find adequate for main saucer lights? Just for laughs I picked up an 1100mcd LED, and *boy* is that sucker bright! You could probably use it for a keychain flashlight! Dunno if it's overkill, though.

Reply to
Casey Tompkins

I wrote a short article on LEDs a while back that may be useful - it's a bit out of date regarding the technology, but the maths still holds true.

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Ant

Reply to
Anthony Hughes

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