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Modified: 18:03, 26 October 2013

Circuit and PCB designed by Phil Townshend, copyright 2002

A 2 digit electronic dice with sound. Shake the die to roll some numbers from 1 to 6. Sound is provided usuing a PCB mounted buzzer.

The displays used were 1inch (25.4mm) common cathode 7 segment hi-brightness types available from Kingbright or Rapid.

The original version used a PIC microcontroller 16F84 which required a crystal or 4MHz resonator. This can be seen in the photo below. Fortunately with the developement of PIC's they are available with internal clock genrators up to 8MHz. A new version of PCB has been made which uses either a PIC16F627 or PIC16F818/9. These are set to run at 4Mhz

This circuit should run on 4.5 to 6 volts, AAA's are adequate. It has functioned on a 9volt PP3 battery but I strongly recommend against this!

Rapid part no:
R1 4K7
R2 omitted
R3-10 100ohms
R11 1K
R12 1K
C1 220uF Elec.
C2 220uF
IC1 PIC16F627/818
T1,2 2N3704
D1 1N4001
Buzzer PCB 6 volt
35 - 0030
SW1 Vibration switch
SW2 SPST toggle switch
Display 1,2 Common Cathode 25mm
57 - 0207
18 pin IC holder
PP3 battery clip

Requires a PIC programmer and assembler.
(Pre-programmed PIC available)

PCB and circuit details version 2 - (pdf format)

A view inside the case - note the 9 volt battery - NOT ADVISED!!!

The case was made from two types of material. The cover was vacuum formed using 2mm yellow polystyrene and small detail added with enamel paints - the ones used for model planes etc.

The base was shaped from 3mm yellow acrylic and bent in a U shape using a strip heated and a wooden former to ensure an accurate size.

A kit is available including PCB, components and pre-programmed PIC from our shop.

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