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and then there was me....
13-01-2009, 12:35 AM
how does one wire a land raider?i have one and i was just wondering about how i should do it.

Arkaedin
13-01-2009, 12:44 AM
What do you need? I can give you a circuit diagram and then a real-life substitute. What's you proficiency with electronics? How many LEDs?

Consadine
13-01-2009, 12:47 AM
The best resource is someone who's already done it before. They'll have the schematics. At the most basic principles, you have a series of switches to control which LED's light up using a battery. Again, easiest done by someone who's already built it. If you put too many volts across an LED, they'll burn out and smell bad, the old ones explode... but look great in a microwave :D

I may or may not have 11k LEDs I found on Craigslist and done some experimenting...

EDIT- When in doubt, ask Ark about things electrical :p

grimdisco
13-01-2009, 01:05 AM
I just get prewired LEDs from toys they are cheaper than buying them new and all the work is dun for you. You may need to extent the wire but that is easy.

Arkaedin
13-01-2009, 01:19 AM
I just get prewired LEDs from toys they are cheaper than buying them new and all the work is dun for you. You may need to extent the wire but that is easy.

LEDs are very cheap, though. And you have the added benefit of not destroying a toy AND the satisfaction of wiring something yourself.

@Consadine- yeah, burning stuff out is all fun and games until you get really bored in a lab and accidentally forget the Power Supply is plugged into the Breadboard while a lone diode is in there with your fingers gripped around it as you turn the Power Supply on and proceed to to burn your flesh. Left a neat scar though :p

REAL fun and games: grabbing some capacitors and progressively putting more and more voltage through to see how far you can launch them :D

Consadine
13-01-2009, 01:22 AM
Very interesting, will have to get my hands on some capacitors... is it more of an explosion than launching? :D

Arkaedin
13-01-2009, 01:33 AM
Very interesting, will have to get my hands on some capacitors... is it more of an explosion than launching? :D

Yep. :D

and then there was me....
13-01-2009, 11:50 PM
@ ark- the diagram and the substitute would be great, thanks!

@grimdisco- i took my LED out of a pen and it kinda works

Arkaedin
14-01-2009, 03:58 AM
Can't give you a diagram without knowing what you want man ;)

Headlights?
Interior Lighting?
Something different?

dad0twins
14-01-2009, 04:03 AM
Hey ark what would you suggest for wiring LED's and an MP3 player into a LR? Headlights and weapons.

KaKlick
14-01-2009, 04:14 AM
Can't give you a diagram without knowing what you want man ;)

Headlights?
Interior Lighting?
Something different?

He's trying to place an LED from a light up pen into the chassis of his Chaos Land Raider. He has the assembly taped into the underside of the LR's roof. It works pretty well and gives the desired "eerie blue light between the plates, tracks, etc." that he's looking for, its just that the LED he's using and its assembly are temperamental and react to physical movement easily thereby shutting them off or causing it to flicker. He's trying to find a way to easily set it up to make the tank have the aforementioned effect, ease of access (via magnets set in the upper hull of the LR), and to make the LED as "shock proof" as possible. Not to mention making it easy to turn off and on.

Arkaedin
14-01-2009, 04:44 AM
@KaKlick/andthentherewasme: Why not just pay the, what, 20 cents for a better LED that's not temperamental?

Simple circuit diagram with explanation:
http://i66.photobucket.com/albums/h245/krazed1189/d1d02556.jpg

Purple = Your voltage source. Doesn't really matter, but it dictates what value resistor (green) you will need. The LEDs I normally use are 1.7V and have about a 20mA tolerance so say you have a 3V Lithium Ion battery (what I normally use for projects) the Resistor you need is calculated by:
R=V/I
where
R= Total Resistance
V= Voltage (which will be Voltage Supplied - LED Voltage tolerance)
I= Current

R= (3 - 1.7) / .02
R= 65Ohms

Since I normally have a bunch of 100Ohm resistors sitting around, I normally just use those, but as long as it isn't TOO much over that 65Ohm value, you should be good. Resistors are disgustingly cheap too.

If you're not sure about the voltage and amperage tolerance of your LED, just fool around with different voltages and resistors, just be sure not to hold the power supply on for too long until you think you've found a good barrier. I buy LEDs in bulk so I have tons of spares just in case.

That basically explains green.

Red is your switch, simple. Most switches will have 3 pins, make sure you only wire two ADJACENT pins. That way the connection can be made to turn the lights on and off.

Blue is your LED.

Since there is only one LED in the circuit, this is a very simple thing to wire up.
If you have any more questions, just ask :)

@dadotwins, follow the same concept. Just connect the LEDs in parallel (that's VITAL since you don't want to split your voltage, you want to keep it the same across each diode). Cut a hole in the bottom of the LR and magnetize it or something (maybe hinge it somehow?) so you can get your mp3 player inside. Just find some cheap mp3 external speakers you can use (there are a bunch that are small) and shove it inside or something. It will be a bit difficult to wire a speaker to the audio output on the mp3 player, and I've never done that before either, so I wouldn't be able to help much with that until I get back home and mess around with my ipod and stuff. Maybe I'll have my girlfriend bring it up this weekend so i can mess with it, I'll get back to you on that because it'll be not only cheaper, but much more convenient to fit into a Land Raider.

phew. :D

Consadine
14-01-2009, 05:06 AM
I think someone might ask about how to wire a parallel circuit as opposed to a series. Bless us once again with your art skills, Ark :D

Arkaedin
14-01-2009, 05:24 AM
Man this would look so much neater with my CAD program, but for some reason I deleted it off my computer >_<

Anyways. . .
http://i66.photobucket.com/albums/h245/krazed1189/b19e8d41.jpg

So you have your DC Voltage supply (a battery), your Resistor and two LEDs.

The blue circle represents Loop 1 and the green is Loop 2.

Loop 1 is the basic circuit I showed you guys earlier. I have a set amount of voltage going through a resistor which then goes through the LED, making it light up, and then proceeds back to the the voltage supply.
With a parallel circuit, we are basically replicating Loop 1 and "pasting" it onto our main circuit.
However, since it is connected in parralel, we have the same amount of volts going through the first LED as we do the second. And since the same amount of voltage is going through each loop, there is only need for one resistor since it decreases the voltage flow to each loop. If I have 5 volts going through my circuit, 5 volts flows through each LED if connected in parallel. If I place a resistor before the loops occur (that is, before the voltage "loops" around the circuit to flow to the diodes) then I am decreasing both loop voltages by the same amount.

In physical terms, You want basically one wire flowing from the positive end of the battery to each positive LED lead and the same for the negative end. If you connect the LEDs side-by-side they will progressively get dimmer as the voltage will decrease at each interval.

Get what I mean?

Arkaedin
14-01-2009, 05:57 AM
I know, I know, a mod double posting, what's up with that?

Just so it's clearer
Series Circuit:
http://i66.photobucket.com/albums/h245/krazed1189/series.jpg

Parallel circuit:
http://i66.photobucket.com/albums/h245/krazed1189/para.jpg

(I found my CAD stuff if you haven't noticed!)

Also, I moved this thread to modeling and painting articles/tutorials as it is more appropriate there.

EDIT- also, the LED diagram is actually a normal diode. For some reason this program doesn't have LEDs in it's library. Annoying.

dad0twins
14-01-2009, 01:49 PM
Thanks Ark.

tarantulus
15-01-2009, 05:16 PM
would the resistance of the wire in loop two cause an issue? or is it too negligible to worry about. (Just remembering my highschool electronics)

Consadine
15-01-2009, 05:34 PM
It shouldn't matter unless you're using an absurd amount of wire inside the Land Raider (over a meter).

Arkaedin
15-01-2009, 07:13 PM
It shouldn't matter unless you're using an absurd amount of wire inside the Land Raider (over a meter).

what he said.

ThePixelGuru
28-01-2009, 02:59 AM
@dadotwins, follow the same concept. Just connect the LEDs in parallel (that's VITAL since you don't want to split your voltage, you want to keep it the same across each diode). Cut a hole in the bottom of the LR and magnetize it or something (maybe hinge it somehow?) so you can get your mp3 player inside. Just find some cheap mp3 external speakers you can use (there are a bunch that are small) and shove it inside or something. It will be a bit difficult to wire a speaker to the audio output on the mp3 player, and I've never done that before either, so I wouldn't be able to help much with that until I get back home and mess around with my ipod and stuff. Maybe I'll have my girlfriend bring it up this weekend so i can mess with it, I'll get back to you on that because it'll be not only cheaper, but much more convenient to fit into a Land Raider.
Stereo wire is really easy, actually. You've got two channels, left and right, and each channel has two wires, positive and negative. Most headphones have those dual wires that look kind of like extension cords - cut it about a foot away from the stereo plug and pull the two halves apart until you have enough slack to work with. Each half is a channel. For the purposes of an MP3 player inside a model tank, it doesn't matter which is left and which is right. If you strip the wire in each channel, you'll either find bare wire and another insulated wire or two insulated wires. Strip 'em - just make sure one is insulated for at least 1/2" past the other so they don't cross and short. Electrical tape will also prevent this, but this step is key to making the process easier and making sure it doesn't wiggle around and cross at some later point in time. Splice your wires them into the corresponding wires for whatever cheap speakers you find. Just like left/right doesn't matter, positive/negative doesn't matter a whole lot, either. Just make sure that you wire both speakers the same way, because if you reverse the polarity on just one speaker it'll interfere with the other, especially in a confined space like a model tank. Keeping both straight or reversing both is fine, so just match the wires the same way in both channels. Wrap this in electrical tape accordingly to keep uninsulated wires from touching each other, and you're done!

Also, a lot of headphones actually get pretty loud without amplification. See if you can find some real loud ones, then break open the housing to make them smaller and easier to mount in the tank. You can also make/buy really small amplifiers, too. A friend of mine used to make them out of Altoids tins and power them with 9v batteries - you wouldn't believe how loud that can get for the size. The benefit of headphones, though, is that they're entirely powered by your MP3 player, so no replacing batteries.

DISCLAIMER: I am not an engineer, nor do I play one on TV (though I did drop out of a great engineering college to become a philosopher). I take no responsibility for electronics that you destroy, stuff you burn, or electrical shocks you or others receive. My advice is not that of a professional but rather a person who destroyed a lot of appliances as a child. Follow at your own risk. :D

Scoppio
28-01-2009, 03:37 AM
I was thinking on placing a few high-bright led and a microcontroler to do some kind of "shinning drop-pod" with blinking lights :D