https://www.analog.com/en/resources/design-tools-and-calculators/ltspice-simulator.html ltspice is free
LTSpice Tutorial - EP1 Getting started Fesz
https://www.youtube.com/watch?v=P_ENvucaZkI
https://ltwiki.org/index.php?title=LTspice_Hot_Keys
https://en.wikipedia.org/wiki/Gain_(electronics)
LTspice #2: Install Libraries; Digital Simulation
https://groups.io/g/LTspice/topic/this_component_can_not_be/69345083
How to link folder to another position with symbolic link (Symlink) - 2 methods !!!
Link Shell Extension for windows explorer
https://gitlab.com/mgyger/ltspice-symbols https://github.com/marcosalonsoelectronics/website https://sites.google.com/view/j-marcos-alonso/home
same author as LTspice mike.engelhardt@qorvo.com supports c++ and verilog as sub-circuits awesome
https://www.qorvo.com/design-hub/design-tools/interactive/qspice/ https://forum.qorvo.com/c/qspice/9
https://github.com/Qorvo/PyQSPICE
https://physics.uncg.edu/hellen/spice_stuff.html https://github.com/marcosalonsoelectronics/website/blob/main/Qspice/MyLibrary.zip
https://gitlab.com/mgyger/qspice-symbols https://github.com/marcosalonsoelectronics/website/tree/main/Qspice
https://github.com/KSKelvin-Github/Qspice/tree/main?tab=readme-ov-file
https://github.com/nunobrum/spicelib https://github.com/ckuhlmann/lt2circuitikz conversion script
https://www.youtube.com/results?search_query=qspice https://www.youtube.com/watch?v=kR2L3j4-Llc&list=PLq_MUr0hT_-kn89_adwe6QNpnLpZtJeI- https://sites.google.com/view/j-marcos-alonso/home