Stepping down voltage

[Matty1973]

I have a question about voltage

I have designed and built a lighting setup for the PL 1/350 NX01 all in 9v, but I am using the Easy LED strips for the nacelles that although work on 9v they are much brighter at 12v

Is there any way of running it at 12v but using something to step it to 9v for the existing setup, and the 12v for the strips

[Matty1973]

Is a 7809 regulator the answer?

[Sparky]

Stepping up has to be done with a circuit, a simple regulator cannot boost up a voltage. There are plenty of circuits for doing this but its a micro chip and some other components to make this happen (switching power supply is basically what you'll be getting).

Also if the strip is designed to run at 9 volts, 12 volts will really run it s life down. You're stressing the LEDs and they'll burn out much sooner (LED life as somewhere around 10,000 hours run-time).

Also you could be starving the LED strips. I'm betting that with a 9 volt battery you are starving the LED strips, a 9 volt battery is made using AAAA batteries! There is a post in one of the stickies about how much current a 9 volt can deliver continuously.

One way to check this is hook up the led strips to the battery and measure the voltage across the battery terminals while all the lights are on and while they are off, if the battery voltage is much lower then 9 volts the LED strips are consuming more power than the battery can give, and the LED strips will appear dim and the battery will not last very long before it gives out totally.

Also it could leak pretty bad if you are over drawing it constantly.

[Sparky]

http://www.powerstream.com/9V-Alkaline-tests.htm

Not that he mentions his test is not to test the batteries under normal discharge loads, but to characterize what happens when you over discharge the batteries. His lowest discharge rate is 100 mAmps.

I'm betting you only want to use a 9volt battery between 10 and 50 mAmps. Even at 50 mAmps you are not running at 9 volts but at 8 volts.

What is the current draw of the led strips? At least 20 mAmps each for modern white and blue LEDs. That's for 2 or 3 LEDs only. Note at 3 LEDs standard white or blues want 3.3 * 3, or 9.9 volts, a 9 volt battery is already starving the strip. with 2 LEDs and a resistor the strip would get what it needs from a fresh 9 volt (starves out as the battery is drained). Some whites and blues want 3.4 volts so a 3 led strip is really running on the lower side of what it can safely take with a 9 volt battery.

In a nut shell 9 volt batteries are not made to power LED light strips or multiple LED lighting setups.

Try running the LED strips off a good 9 volt wall power supply, something that is regulated, check its voltage without anything hooked up and with the LED loads, the output voltage should be right at 9 volts and some change. It will say regulated.

[Sparky]

Wait I think the strips are meant to run at 12 volts, and everything else needs 9, the voltage regulator is the simple way to go and is all you need.

Check it in use though they tend to get hot, inside the model that heat build up will cause yellowing of decals and paint and softening of plastic if not melting of it.

[Matty1973]

Wait I think the strips are meant to run at 12 volts, and everything else needs 9, the voltage regulator is the simple way to go and is all you need.

Check it in use though they tend to get hot, inside the model that heat build up will cause yellowing of decals and paint and softening of plastic if not melting of it.

Yes that's right, 12v dc in, regulator to run the 9v setup and 12v to the led strip

[Tchail]

I've run into the same problem.

For my Enterprise D, I wanted to use a 9v blinking light circuit and 9v for LEDs, but the EL panel for the nacelles runs off of 4.5v.

The only solution I could find is the DC/DC converter breakout, available through Sparkfun:

http://www.sparkfun.com/products/9370

I purchased it, but I have not actually used it.

Hope this helps,

-Tchail