I can now safely say the #CherryZXKeyboard project rescued at least one #zxspectrumplus over at my end. Next thing is to find the right output levels to load something on the #zxspectrum from a dozen of tapes here. Keyboard project on GitHub: https://github.com/VlastimilWagner/CherryZXKeyboard
GitHub - VlastimilWagner/CherryZXKeyboard: Keyboard for ZX Spectrum based on 48p-KDLX scheme, but used Cherry MX and atypical formfactor

Keyboard for ZX Spectrum based on 48p-KDLX scheme, but used Cherry MX and atypical formfactor - VlastimilWagner/CherryZXKeyboard

GitHub