This is a little circuit to connect your MD or DAT to your CD-ROM drive with standard optical cable.. Parts cost about 50 FIM.
This circuit is tested by me with no problems with locking to signal. Sources were Creative Infra CDROM and Creative Labs AWE32 soundcard. Recording device was SHARP MS-200H Minidisc.
This EPROM Emulator was designed to compliment the EPROM Programmer (Mark 2). An EPROM Emulator can save a vast amount of time when developing software, compared to programming and erasing EPROMs.
The unit is powered from an external PSU, since this is cheaper than buying the individual parts! One of the low cost unregulated types with an integral mains plug is suitable, providing it is capable of supplying between 10 and 18 Volts DC at 500mA without too much ripple, the voltage regulator U21 will run cooler if the voltage is nearer the lower end of this range. The types sold for powering electronic keyboards appear to be the most suitable. The prototype is powered by an old Sinclair ZX81 PSU (type UK1200).
This simple power supply unit was designed for use with the EPROM Programmer Mark 2. It is equally suitable for powering the EPROM Emulator.
Records user keystroke activity to internal EEPROM memory. Simulates keyboard operation for data retrieving. Schematics, 8051 source code and PC application for data download are provided.