Blue Plastic Tracks

Tramp:

In another thread, while discussing LED lights & Voltage, you mentioned this neat little Step Up Power Converter on Ebay and that you were going to try it out. Did you ever give it a try?

The reason I ask is that your post piqued my interest and I bought a couple seeing as they are so inexpensive. They look pretty easy to install with the drawing and should be perfect for installing LED lights in a string of coaches. Have you had the chance to wire one up? Also I had been wondering about the size and you can tell by the picture it is quite small 15/16" x 1/2" Plenty small enough to easily install in any coach, tender or rolling stock.

Sorry no, they're still on my watch list I do intend to get them at some point though! They do seem like a good idea but I did notice there are some specifications, if you use an AA battery or AAA battery the load needs to be between 50-120mA generally a white led takes 20mA so you need a minimum of x3 leds (you will probably get away with x2) and a maximum of 6, this booster looks like it's designed to power white LEDs as it's output voltage is 3.3 which is exactly right

Booster from AA you need x3-x6 white LEDs

If you want red LEDs it's different as they require 2.2v to run so you have to fit a resistor, so you need to take into account that the resistor will use some current to, the led still requires 20mA, for 3.3v you need a dropper resistor of 56ohm, this resistor will drop the volts but will use some current itself ~20ma, so if you use a red led with resistor it will use 40mA per Led, so. If you use this booster you could power 1 - 3 LEDs, really if you stay in the current limit if the booster you should be able to mix and match red and whites,

The thing that let's this fall down is some LEDs don't use 20mA some use more and some use less! But we can work out what is needed if you post the values!

Finally, flashing amber LEDs, great! But they use 20mA only when they are on, so you will need to have enough whites and reds to keep the minimum of 50ma load on the booster pack before you use the flashers

I've done it and ordered some, They do look perfect,

Thanks Tramp

Have I told you what a great asset you are to these Forums? Well...you are. Our very own, resident expert in electrical & lighting issues.

Thanks for all the info as I appreciate the lessons and learn so much. I am glad that you have ordered a couple of these step up converters as I can't wait to see what you come up with. I wonder how they work? As far as resistors are concerned I am trying to just buy LED's that already have them installed. Sort of like "LED for Dummies" to take out my guess work. It is nice to know though, that I can come here for your advice if and when I do have to add them myself.

My first idea and project that I want to use these with is to light up many passenger coaches together but I have so many projects ahead of it I am not sure when I will tackle it. It will be easier to modify a coach with only a single AA or AAA battery holder than a double one. Here is a question...even though my plan was to use LED's for this project, how would this work using 3 volt incandescent grain of rice/wheat lights if I want less luminescence?

Expert is to strong a word, I know a little and am happy to share. With regards to an incandescent bulb, I don't know what wattage they are but I would imagine it to draw around 100mA, if it does, you would only be able to use one lamp per booster pack, to be honest you may as well use your 1.5v lamps straight from an AAA battery,

Thanks Tramp

It didn't occur to me that the incandescent lights would use more power

Yeah, it's surprising really, but that's why all new energy saving lighting is mostly led based, the thing with LEDs is they have no heat byproduct, so the majority if the energy turns to light, if you don't like the ordinary white led, they do different tones like warm white, or pale yellow, but they are all quite 'stark' when compared to an ordinary filament lamp

Geesh...its so simple, why didn't I think of that...Doh! Thanks again.

Would you know which white LEDs would have the lowest brightness? Or maybe there is a chart somewhere I can refer to. I can't seem to find one. Also is there a way to dull down brightness, I seem to remember you talking about your flashing yellow Salty lights where you colored the lenses.

Well, that's it, I've moved house now and I had some of these step up boards arrive in the post, today I installed one on the flashing salty, the problem I had with the battery and the flashing lights was when the flashing led was lit, the battery cell struggled to power the main light, so as it was running the main light was flickering with different brightness, today I installed the booster and.... Much better, it still flickers a little, but no where near as badly as before, I highly recommend these little boosters!

The circuit working



How it fits in the body



Top job!

And a wiring diagram, sorry super I missed your previous questions,

Yeah you can reduce the voltage to dull the LEDs Down by using a resistor, but it is a waste of battery power and doesn't alter the colour of the light at all, on my salty beacons I had some modellers paint (it wars 'tamiya') and I used the orange wash on the LEDs face to keep it looking amber all the time, I'm sure you could do this with a yellow wash or similar, although it won't change the led colour,