Propeller Clock
"Propeller Clock" Mechanically Scanned LED Clock
Seven light emitting diodes spin, giving the illusion of numbers in the air
An Overview:
Top View Side View
How this clock works:
A motor spins the "propeller", and a small microprocessor keeps track of time and changes the pattern on seven LEDs with exact timing to simulate a 7 by 30 array of LEDs. It is an illusion, but it works nicely.
To build this clock, few things are needed, including: 1. Skill with motors and mechanical things. 2. Prior electronic experience. 3. A dead VCR or floppy drive or other source of a suitable motor and miscellaneous parts. 4. A programmer that will program a PIC16C84 or 16F84 microprocessor.
Schematic Diagram:
The Propeller Clock Parts List:
1. Capacitors: • C1, C2 - 33pf ceramic • C3, C6 - 0.1uf ceramic • C4 - 47uf electrolytic • C5 - 47,000uf supercap(memory cap)
2. Diodes: • D1-D7 - light emitting diodes • D8-16 - 1N4001 general purpose 1amp rectifiers
3. Resistors: • R1 - 120 ohm DIP array or seven 120 ohm resistors • R2-R6 - 10k ohm
4. Misc: • J1 - three terminal Berg connector • SW1-SW3 - normally open pushbutton switches • U1 - PIC16C84, PIC16F84 or PIC16F84A • XTAL1 - 4MHz crystal • MOTOR - Sharp RMOTV1007GEZZ
Note: U1 to be programmed with mclock hex file
A full description how to build it:
Step One: Mangle a Motor:
Find a VCR, perhaps a Sharp or a Samsung, with a flat reel motor. The motor I have is marked JPA1B01, but Sharp knows it by the number RMOTV1007GEZZ. Take it apart without mangling the brushes (there are little holes to slip a paperclip into to move the brushes out of the way), and notice that it has one ball bearing and one sleeve bearing.
Knock the sleeve bearing out of the case and glue or solder it to the other end of the motor, as an extension of
Seven light emitting diodes spin, giving the illusion of numbers in the air
An Overview:
Top View Side View
How this clock works:
A motor spins the "propeller", and a small microprocessor keeps track of time and changes the pattern on seven LEDs with exact timing to simulate a 7 by 30 array of LEDs. It is an illusion, but it works nicely.
To build this clock, few things are needed, including: 1. Skill with motors and mechanical things. 2. Prior electronic experience. 3. A dead VCR or floppy drive or other source of a suitable motor and miscellaneous parts. 4. A programmer that will program a PIC16C84 or 16F84 microprocessor.
Schematic Diagram:
The Propeller Clock Parts List:
1. Capacitors: • C1, C2 - 33pf ceramic • C3, C6 - 0.1uf ceramic • C4 - 47uf electrolytic • C5 - 47,000uf supercap(memory cap)
2. Diodes: • D1-D7 - light emitting diodes • D8-16 - 1N4001 general purpose 1amp rectifiers
3. Resistors: • R1 - 120 ohm DIP array or seven 120 ohm resistors • R2-R6 - 10k ohm
4. Misc: • J1 - three terminal Berg connector • SW1-SW3 - normally open pushbutton switches • U1 - PIC16C84, PIC16F84 or PIC16F84A • XTAL1 - 4MHz crystal • MOTOR - Sharp RMOTV1007GEZZ
Note: U1 to be programmed with mclock hex file
A full description how to build it:
Step One: Mangle a Motor:
Find a VCR, perhaps a Sharp or a Samsung, with a flat reel motor. The motor I have is marked JPA1B01, but Sharp knows it by the number RMOTV1007GEZZ. Take it apart without mangling the brushes (there are little holes to slip a paperclip into to move the brushes out of the way), and notice that it has one ball bearing and one sleeve bearing.
Knock the sleeve bearing out of the case and glue or solder it to the other end of the motor, as an extension of