There is a presentation of my projects to an amazing computer ZX Spectrum 48K/128, Didaktik M, Gama etc.
Beta Disk 128C Controller

•  Beta Disk 128C is a controller for 1 to 4 floppy disk drives 3.5" or 5.25" for ZX Spectrum and compatible  computers. It comes from the original interface of the same name from British company named Technology Research  Ltd.

•  It is fully compatible with the ZX Spectrum 48KB, 128KB "toast rack" and 128K +2 Amstrad gray box. It is also  compatible with other ZX Spectrum clones with a standard system connector and ROM compatible with ZX Spectrum 48KB  or 128KB, for example Didaktik M. Didaktik Gama can be connected after additional fixing, see next description.

•  Interface is incompatible with the ZX Spectrum +2A, +2B and +3.

Beta Disk box for two floppy drive 3.5"

•  Plastic box (3d printing) for two floppy drive 3.5" primarily for Beta Disk 128C. Includes + 5V power supply to  power both drive and controller.

•  Electronics allows switching drives according to DS0 / DS1 signal setting from factory and selecting drive A, B,  C, D for each drive.

External ROM card 64KB

The card is ideal for testing, repairing and programming on the ZX Spectrum

•  Small in size, compact to fit onto ZX Spectrum edge connector
•  64KB memory capacity: Up to 4 optional 16KB ROMs
•  Select ROM by rotating BCD DIP switch, position 0-3
•  Completely through bus to connector identical to ZX Spectrum edge connector
•  Generator and NMI signal button
•  RESET button

External ROM card 128KB

The card is ideal for testing, repairing and programming on the ZX Spectrum

•  Small in size, compact to fit onto ZX Spectrum edge connector
•  128KB memory capacity: Up to 8 optional 16KB ROMs
•  Select ROM by rotating BCD DIP switch, position 0-7
•  Completely through bus to connector identical to ZX Spectrum edge connector
•  Generator and NMI signal button
•  RESET button
•  Possibility of blocking external ROM by hardware or software
Multishots interface

Interface for two players with two joystick - indispensable for collective players !

•  Allows to connect up to two pieces of Quickshot-compliant joystick (4x direct + 1x fire) through the 9-pin D-SUB connector

• The device emulates the joystick connection to your computer in four standard modes:

    • Interface 1 (Sinclair 1 LEFT) - keystroke emulation 1 to 5
    • Interface 2 (Sinclair 2 RIGHT) - keystroke emulation 6-0
    • Cursor (Protek) - keystroke emulation 5,6,7,8,0
    • QAOPM - keystroke emulation QAOPM

Multiface 128C ver. 1

• Multiface 128C is the peripheral device for the Sinclair ZX Spectrum 48KB and 128KB computers. He can stop a
running program, monitor the contents of memory and registers of the processor, and save the current contents of
memory or screen to the media by pressing the NMI button (the red button).

• Hardware copy of the original scheme from company Romantic Robot, in which some minor modifications were made:

    • The original 8KB ROM is replaced with a new 16KB ROM, which the user selects with a switch to which half he wants to be active. This makes it possible to choose from two different operating systems
    • Current boost of output signal ROMCS by transistor
    • Separate the output signal NMI by the diode to avoid collision with the NMI signal from any other connected peripheral
    • Removing nonsense with two 74LS00 chips, now just one
    • Added two LEDs - one POWER and one MULTIFACE ACTIVE

Used ports:

    • 159d / 9Fh: Multiface memory activate
    • 31d / 1Fh: Multiface memory deactivate
Orpheus interface

Combined joystick & AY-sound interface  - indispensable for any player !

•  Sound interface is full compatible to similar interface on ZX Spectrum 128KB

• Joystick interface emulates the joystick connection to your computer in four standard modes:

    • Interface 1 (Sinclair 1 LEFT) - keystroke emulation 1 to 5
    • Interface 2 (Sinclair 2 RIGHT) - keystroke emulation 6-0
    • Cursor (Protek) - keystroke emulation 5,6,7,8,0
    • QAOPM - keystroke emulation QAOPM


Multiface 128C ver. 2.5

• Multiface 128C is the peripheral device for the Sinclair ZX Spectrum 48KB and 128KB computers. He can stop a
running program, monitor the contents of memory and registers of the processor, and save the current contents of
memory or screen to the media by pressing the NMI button (the red button).

• Hardware copy of the original scheme from company Romantic Robot, in which some minor modifications were made:

    • ROM 16KB, switch selectable two versions of system
    • Switch selectable I/O port addressing (old 31d + 159d or new 63d + 191d)
    • Current boost of output signal ROMCS by transistor
    • Separate the output signal NMI by the diode to avoid collision with the NMI signal from any other connected peripheral
    • Removing nonsense with two 74LS00 chips, now just one
    • Added two LEDs - one POWER and one MULTIFACE ACTIVE

Used ports:

    • 31d & 159d, or 63d & 191d by the switch

Kempston interface

Interface for Kempston joystick - indispensable for all player !

•  Allows to connect a Quickshot-compliant joystick (4x direct + 1x fire) through the 9-pin D-SUB connector

• Standard joystick connection on port 31d/1Fh

• Support in huge amounts of software

Advanced parallel interface ADPI8255A

•  ADPI8255A is an improved version of classic three-bidirectional parallel port interface

•  It is based on the Intel 8255A chip or equivalent. Includes 1x Kempston joystick connector, 1x printer connector, 1x united connector for A, B, C parallel ports and four supplementary inverters.

•  Interface is compatible with all versions of ZX Spectrum or clone.