🇧🇾 Квант (Quantum): Part 1 [TCE #0452]
28Let's have a look at this Belarusian Sinclair ZX Spectrum clone called the КВАНТ (KVANT) or Quant(um) in English.
It's labelled "КВАНТ МИКРО ЗВМ" where ЗВМ is an abbreviation for "Электронная Вычислительная Машина" ... Electronic Calculating Machine ... so it's a "Quantum Micro Computer".
I'm not sure if КВАНТ should be "quant" or "quantum" in English - going with "quantum".
It came with half of the polys, power supply (220VAC to 5VDC), joystick and cassette. The machine itself has one joystick port (using a non-standard 2x4 pin connector), a 5V input socket (using the same 2x4 pin connector), a DIN5 cassette (magnetophone) socket and a DIN5 RGBS output socket for video.
Cleverly, if you insert the power plug into the joystick socket there should be no harm as they do not use the same two pins as the power socket uses - they are left unconnected.
It also includes a reset button.
It has no other expansion, including on its motherboard. It appears to have an East German U880D clone of the Zilog Z80, but uses a pair of Western 8KByte EPROMs. All other parts are Soviet-era.
It doesn't utilise a ULA (yay!), just discrete logic which greatly helps with troubleshooting.
In includes a full size speaker.
The keyboard is, well, pretty rubbish. It's functional and won't have an issue with degrading rubber contacts, etc. but just doesn't feel that nice to use.
The included joystick is one of the better ones I've encountered from the former Soviet territories. The stick itself is of metal construction and the way its constructed should ensure it still works. It is, however, let down by the buttons - a bit too mushy for my liking. It include three fire buttons in total - two ambidextrous button on the base and one on the top of the stick.
{Updated 24-May-2024, thanks to @LastofAvari}
Lots of excellent information (in Russian), including documentation & circuit fixes:
https://zxbyte.ru/inter.htm