| PCB | Printed Circuit Card | 200,001 issue 2 or later |
| IC1 | CD4024B | and 14 pin socket |
| IC2 | CD4024B | " |
| IC3 | CD4011B | " |
| IC4 | CD4013B | " |
| IC5 | CD4001B | " |
| IC6 | CD4024B | " |
| IC7 | LM358 | and 8 pin socket |
| R1 | 3K9 resistor | |
| R2 | 47K resistor | |
| R3 | 4K7 resistor | |
| R4 | 1K resistor | |
| R5 | 10K resistor | |
| R6 | 4K7 resistor | |
| R7 | 4K7 resistor | |
| R8 | 47K resistor | |
| R9 | 4K7 resistor | |
| R10 | 4K7 resistor | |
| R11 | 10K resistor | |
| R12 | 47K resistor | |
| R13 | 4K7 resistor | |
| R14 | 470K resistor | |
| R15 | 4K7 resistor | |
| R16 | 4K7 resistor | |
| C1 | 100pF capacitor | |
| C2 | 1nF capacitor | |
| C3 | 10nF capacitor | |
| C4 | 1nF capacitor | |
| C5 | 15uF electrolytic capacitor | |
| C6 | 47 or 100 nF capacitor | |
| C7 | Not fitted | |
| C8 | 22nF capacitor | |
| C9 | 47 or 100 nF capacitor | |
| C10 | 47 or 100 nF capacitor |