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WORKING Christmas Tree Project Circuit

Hypermung

By Hypermung
in WIP: Drag Racing Models

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Hypermung MCM Friend

Hypermung

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Hi Guys. I've been experimenting with some simple electronic circuits lately & thought someone here in the 'Drag' section could find some inspiration to build a 'WORKING' christmas tree out of coloured LED's. Now whilst the circuit may look complicated, it is actually simple to read. If you can read a road map you should be able to follow this. The circuit for the christmas tree comprises two cheap & readily available integrated circuits (ICs): a 555 timer & a 4017 decade counter. The 555 is wired as an pulsing oscillator in the simplest configuration possible, using only 2 additional components. This 'pulse' is fed into the input of IC2, which is called a 'decade' counter' because it counts to 10 (0 to 9) each time it detects a 'pulse' on pin 14. Each time IC2 is pulsed, it switches on the associated transistor (basically a 'switch') & the 3 LED's. For example, when the first output ("0") at pin 3 of IC2 is powered, transistor Q1 is switched on via the 10k base driver resistor. This transistor powers LED's 1,2 & 3 via the 1k current limiting resistor. This process is repeated for each output in turn (ie: 1,2,3,4 etc) each time IC2 is pulsed. ChristmasTree.jpg............ You can see that the 3 amber LED's on outputs 0-4 will light up in turn then go out (counting down from the top of the tree, so LED's 1,2 & 3 will occupt the top amber position of the tree, 3,4 &5 the second position etc). When the output on 4 is pulsed the green (GO) LED's come on, but as we want the green to stay on (& not go out), the outputs 5-9 are fed into the same green circuit using diodes (one way valve) to stop any back-feed into IC2. This way, the amber lights count down in turn (outputs 0-3) then the green stays on for 5 counts (outputs 4-9) before IC2 resets itself (via pin 15) & the process repeats itself again & again. I have also added 3 white LED's (LED 16, 17 & 18) that come on (& stay on) as soon as the circuit is switched on to simulate 'Staging' lights. Don't let the look of this circuit frighten you. As I said if you can read a road map you should be able to follow the 'Streets' on this. Think of the transistors as 'traffic lights', diodes as 'One way streets', & resistors as 'Speed humps'. I haven't put together a component list yet, but I'll get one together & post it if anyones interested. I know this is not an 'Electronics' forum, but this is something we all can use to take our dioramas to the next level.... I also have circuits for Fire / Police flashing lights, light 'Chasers' for billboards / diners etc, Knight Rider circuits, all using basically the same circuit with a few mods. Let me know if you think this is appropriate for this forum, & I might start a thread in the 'Tutorials' areaComponentIdentification.jpg

eviltwincustoms MCM Ohana

eviltwincustoms

Posted
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This is a great idea, thanks for posting this. I would need to brush up on my electronics unless you are planning on posting all the values that would be needed for each part. Basically just buy an electronics peg board and run small wire connectors to each and solder. Brings me back to my High School days building a basic computer.

Hypermung MCM Friend

Hypermung

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This is a great idea, thanks for posting this. I would need to brush up on my electronics unless you are planning on posting all the values that would be needed for each part. Basically just buy an electronics peg board and run small wire connectors to each and solder. Brings me back to my High School days building a basic computer.

G'day Bart. I will post a component list (when I make one up later). Check back next time. You may have to experiment with the value of the 22k resistor @ IC1 to get it to the speed you want the lights to flash. A larger value will slow the tree down, but as these resistors are only a few cents each, you can get a few larger ones & use which ever one in appropriate to obtain the speed you want.

Hypermung MCM Friend

Hypermung

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G'day Bart. I will post a component list (when I make one up later). Check back next time. You may have to experiment with the value of the 22k resistor @ IC1 to get it to the speed you want the lights to flash. A larger value will slow the tree down, but as these resistors are only a few cents each, you can get a few larger ones & use which ever one in appropriate to obtain the speed you want.

Later on (when I get a composent list together) I'll also modify the circuit to include 3 red LED's (that come on with the green), & can be turned on or off as required.

Hypermung MCM Friend

Hypermung

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Ok gang. I've been playing with the same circuit again & added a component list. All these components are readily available @ your local Radio Shack, or Tandy, or whatever you have over there (over here in Oz it's Jaycar). As promised, I've also added a few more components to simulate the poor SOB redlighting EVERY time (if you want). You'll see I've added a switch, a diode & a transistor to the collective 5,6,7,8 & 9 outputs, so that when IC2 reaches it's '5' count (if the switch S2 is in the 'on' position), the output also triggers Q6 to switch on, illuminating the 3 'redlight' LED's as well as the 3 green LED's. You gotta pity the fool. He'll redlight every time, until you switch S2 to the 'off' position, then outputs 5,6,7,8 & 9 will only light the green because D2 & D8 (one way valves... remember?) direct the voltage to the transistor for the green string of LED's only. I've also added another 3 white LED's to the staging @ the top of the tree. I'm trying to have this as simple as possible, so If there's something you don't quite follow, just post a question.ChristmasTreeMk2.jpg

  • 2 weeks later...
  • 4 years later...
wdrfcj Looker

wdrfcj

Posted
Posted

has anyone built the model christmas tree. does anyone have a photo of a printed circuit for the christmas, that i  can copy and make a circuit board for the Christmas tree. i built one and am having problems with it , the lights done cascade down as they are supposed to , the all stay on steady except the red which doesnt come in at all.i have studied my work and am not able the find the problem. i have swapped out the integrated circuits with no results

disabled modeler MCM Ohana

disabled modeler

Posted
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Richard... I have wanted to do that for many many years myself...wish I could too.  I always wanted to make a drag strip diorama with a working tree and a working or chasing light marque sign or two.

wdrfcj Looker

wdrfcj

Posted
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why are the numbers on the integrated circuit different from the ones on the outside of the integrated circuit. this can be confusing when wiring, i am assuming the numbers on the outside of the circuit are the pin numbers. Hypermung designed the circuit and was hoping he could shed some light on this.

thanks Richard

Erik548 MCM Friend

Erik548

Posted
Posted (edited)

just posting an idea since alot has changed since 2011, go buy yourself a raspberry pi zero for $5 hook each of the LEDs to an output and it can all be done in software without complicated wiring 

Edited by Erik548
Mooneyzs MCM Ohana

Mooneyzs

Posted
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This is totally cool. I have been wanting to do one in 1/16th scale. I may just have to pick up one of those rasberry pi's for $5.00 and try to mess around with one of them

 

  • 1 year later...

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