Humble48 ZX Spectrum 48k clone, 100% compatible with the original. Fits into a rubber/48k+ case and connects to the keyboard membrane.


This board has been developed by BCH at VadeRetro Forums, based on Superfo designs. ULA implementation based on code by Miguel Angel Rodriguez Jodar, reworked by Superfo. Latest optimized firmware by Kyp can be dowloaded from this thread:



    The Humble48 is a clone of the original Sinclair ZX Spectrum 48k. It includes a real Z80 and implements a cicle-exact ULA on a CPLD.


    The board includes all the ZX Spectrum standard connections; ear, mic, expansion edge, power, and membrane keyboard. It also features composite video output RCA jack and RGB output through a miniDIN 9 connector (this connector is only accessible by modifiyng the Spectrum case). 


    As optional, a Kempston Joystick interface and a reset button can be soldered on board. These two options, as well as the RGB connector will require to modify the ZX spectrum case in order to fit in.


    • 100% with the Sinclair ZX Spectrum 48k
    • Cicle-exact CPLD ULA
    • Fits into ZX Spectrum 48K/48K+ cases.
    • On-board Spectrum 48k membrane keyboard connectors. It can use original ZX spectrum keyboard.
    • Composite Video Output
    • DIN9 RGB connector (Sega Megadrive pin compatible)
    • EAR and MIC tape input/output jacks.
    • DC power jack connector. Supports 7v to 28v PSUs (9v to 12v recommended), any polarity, 2 Amps. Supports original ZX Spectrum 48k PSU.
    • Optional RESET push button.
    • Optional Kempston Joystick interface on-board.
    • Dual ROM support

    In order to get a replacement or refund defective units must first be returned. Once the item has been inspected we will proceed to replace the unit or refund the payment. Items that have been damaged by careless/unadecuated use or modifyied by the buyer in any way will not be elegible for replace or refund of any kind. 


    The unit ships with the lastest stable firmware available. Notice that if you accidentally brick the unit by wrongly updating/downgrading the firmware/cores, we do not give tech support for the reflashing process. If you want to keep your board under warranty you should send it back to us for review/reflashing.