4QD's Interesting Circuits ;
CIRCUIT LAB;
DIBs Electronic Design;
Electrical Engineering Circuits Archive;
FC's Electronic Circuits;
Circuit Cookbook Archive;
Circuit Land;
IR-related ASCII Schematics V1.00;
Wenzel Associates Technical Library;
WE-MAN!;
Electronics On Ramp Circuits and Schematics Page;
Daphnis Home Page;
Página de Luiz Bertini e Luciana;
Eletrônica Total-projetos,download de apostilas;
Eletrônica Digital-Sanka Page;
Eletrônica Virtual;
O site da eletronica : apostilas;
Oscilloscope Block Diagram and Schematics;