Handbook of hardware schemes, cables layouts and connectors pinouts.

https://pinoutguide.com/

WSPR MET DE RASPBERRY PI

https://pd3rfr.nl/experimenten/raspberry-pi/wspr-op-de-raspberry-pi

HDD and other storage devices connectors pinouts
https://pinouts.ru/HD/

Condensator codes
https://www.budgetronics.com/index.php?action=extra&extra=A_condensator_codes&lang=NL

Schakelingen, download, info en meer
https://www.circuitsonline.net/