Sinclair
Sega gamepad (replica) tested on ZX Spectrum joystick interfaces
Tested cheap gamepads today that are available on several websites (including ZXSpectrum.shop) on a couple of joystick interfaces.
Works great!
 

The remark at the end of the video about potentially shorting 5V to ground does not apply: the gamepad works well on all interfaces I tested, including DivMMC EnJOY! interfaces with integrated joystick port that have 5V on joystick pin 7.

 
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