It is a neat application designed to create patterns.
the Qucs team
Quite Universal Circuit Simulator is an integrated circuit simulator.
University of Colorado
Build circuits with resistors, light bulbs, batteries, and switches.
New Wave Concepts Limited
Combines circuit design, simulation and CAD manufacture to realize projects.
Free Software Foundation, Inc.
The FMC Stencils are templates and extensions for Visio or OpenOffice Drawing.
Amazing Visio is a toolset which improves drawings in Microsoft Office Visio.
Circuit Shop allows you to design electronic circuits.
Create flowcharts, network diagrams, floor plans, and other designs.
Richard P. Andresen
Use analog circuit simulation for the professional circuit designer.
Cadence Design Systems, Inc
PSpice Student is an analog circuit simulator designed for students.
AIM-Spice is the most commonly used analog circuit simulator today.
AnadigmDesigner 2 lets you design and implement dynamically analog circuit.
Linear Technology Corporation
LTspice XVII is an analog circuit simulation software tool.
The UML stencil for Visio supports complete UML, SoaML and other UML profiles.
Build your circuit by dragging and dropping Configurable Analog Modules.
The Extron AVT 100 is a compact analog cable and closed circuit TV tuner.
Wave Arts, Inc.
An accurate circuit simulation of a tube pre-amp with analog EQ.
AIR Music Tech GmbH
Vacuum Pro is a polyphonic analog synthesizer with vacuum tube circuit modeling.