Introduction: Free Form Christmas Tree
Freeform circuits, or dead bug, or point-to-point constructions are a good way to start prototyping without making a PCB, and are much more flexible than a strip/perfboard!
I often use this technique for small projects or to debug bigger ones. But the other cool thing about free form circuits is that they look nice! You can play with the components and the wires in 3D, creating a lot of different shapes, much more than with a simple PCB.
In this instructable I will show you how to make a blinking Christmas tree, and teach you the basics of freeforming.
You will need this:
- Thick wire (I used 2mm brass wire, and it's a little too big, but standard copper wire seems nice)
- Components for your circuit!
- A soldering iron
- Thin pliers
- Small wire cutters
Step 1: The Circuit
This circuit can be separated into three parts: the oscillator, the inverter, and the LEDs.
The oscillator is made around the well-known NE555, I calculated the values of the resistors and the capacitor using a really useful Android app: ElectroDroid.
Okay, now that we have a blinking signal, we need to find a way to power the LEDs through only two wires (the two parts of the tree). We could choose to light them all in sync, but that would be nicer to blink them alternatively, no? As the LEDs light up only with a positive voltage across them, we can make two groups in opposition and create an alternating positive/negative voltage across them.
To do that, we will need a not gate, made with two transistors in Push-Pull configuration.
Step 2: How to Bend a Tree
Start by drawing the shape of a tree, and then bend the brass wire along it, using thin pliers.
Once you've done the first part, bend a second one, following the first, to make them identical.
Step 3: Soldering - the Blinker
I started by soldering the 555 and all its components to make it oscillating. I used two long and thick copper wires for the power lines, that also act as a stand.
Step 4: Soldering - the Tree
Then you can solder one leg of one part of the tree to the pin 3 (output) of the 555. After that, put in place the second part of the tree, and hold it by soldering some LEDs between it and the first part.
Step 5: Soldering - the Not Gate
It's almost done! Just add the not gate between one leg of the tree and the other.
Step 6: Bending the Battery Holder
Then bend the two power wires so you can put at least two coin cell batteries (6V, you can go up to 5 batteries, or 15V). Watch out the polarity!
At this point, the LEDs should blink.
Step 7: Enjoy !
Solder some more LEDs between the two parts of the tree, and it's done!