Reference:
Analog Engineer’s Pocket Reference
Simulation:
LTspice Website
LTspice Hotkeys
LTspice Add a Model
LTspice Swept Resistor
LTspice Swept Potentiometer
Op Amps:
Op Amps For Everyone PDF Book
Handbook of Operational Amplifier Applications
Op Amp Circuit Collection (AN-31)
PCB Layout:
Kicad Recent Builds
DipTrace Downloads
PIC Dev Boards:
PIC_Dev_8
PIC_Dev_14
PIC_Dev_28