DIY laser spirograph (part 4)

How to build spirograph controller from a kit. Step by step assembling guide.

NOTE!!! Given information is provided for visual reference and may not reflect latest design changes and modification but every ordered kit supplied with updated schematic and component map. 

Kit includes PCB, preprogrammed with latest firmware microcontroller PIC18F1320 and all electronic components to build controller for advanced laser spirograph.

Complete part list:
 
1 x Capacitor 100nF          
1 x Pol Capacitor 100uF      
2 x Pol Capacitor 10uF          
1 x Diode 1N4148           
3 x 2N7000 MOSFET           
2 x Resistor 10K          
4 x Resistor 330R            
3 x Potentiometer 10K          
1 x Resistor 10R          
1 x Resistor 240R          
1 x Potentiometer 1K          
1 x SPDT Toggle Switch       
1 x preprogrammed microcontroller PIC18F1320    
1 x MC78M05ACT Voltage Regulator   
1 x LM317BT Adj Voltage Regulator   
1 x DIP-18 socket           
1 x ICSP Header, 5-Pin       
1 x PCB                

As electronic device, controller is pretty simple and assembling requires only basic soldering skills and minimum set of tools:

 - multimeter;
 - soldering iron, liquid flux, wire solder;
 - fumes extractor (or work in well ventilated area);
 - tweezers, pliers, wire cutter, small flat screwdriver;
 - 22 AWG stranded wire;
 - alcohol, soft brush;
 - heat shrink tubing;
 - glue gun.

DIY laser spirograph (part 3)

PIC based controller for laser spirograph.

The most advanced and sophisticated laser spirograph can be built only with programmable microcontroller.
Design of my spirograph is based on 8-bit microcontroller PIC18F1320 from Microchip.

PIC microcontroller implements software PWM generator with 3 independent outputs. Each output drives 2N7000 MOSFET (can be replaced with any suitable N-channel transistor with gate threshold voltage <5V). Fan is connected as load for MOSFET.
Device supports 5V and 12V fans with working current up to 200mA. Fan's voltage is selected by jumpers on board.
All  PWM outputs generate signal of the same frequency but duty cycle (0-100%) can be set individually for each output.

DIY laser spirograph (part 2)

Manual motor control.

The simplest and cheapest  way to control speed of DC motor is by using variable resistor connected in series with motor.
This method is applicable to any low power DC motor like 3V pager motor. Direction of rotation is selected by switch.
If you want to use chip cooling fans in your design, keep in mind that it's impossible to reverse cooling fan simply by switching power polarity since fan assembly incorporates electronic driver which is designed to maintain motor speed and direction of rotation.

Motor control. Simplest way.