This applet can be used to build and analyze DC and AC electrical circuits.
When the applet is loaded a default circuit is build. It is extracted from a text file that can be found at "lists/default.txt" in the directory containing the jar files. To load another build file, type its name and press the "Load" button. To open a new window with the list of loadable text files, click here. If you want to see a text list of the elements currently on the screen, press the "List" button.
If you want to change the size of the circuit grid, change the number of rows and columns and then press the "Set grid" button. Be aware that all components on the screen will disappear.
The "Show ->" button is used to visualize arrows representing the chosen current direction.
New components for the circuit are entered by a "drag and drop" method. Press the button of the component you want to add, hold the mouse button and release it on the position where you want to put this component. Any horizontal or vertical position between two black dots can be taken.
The following direction
independent components can be added:
Resistor: its value (in Ohm) can be
entered next to the resistor button.
Capacitor: value entered in Farad.
Inductor: value entered in Henry.
Light bulb: characterised by voltage
(in V) and power (in W). The color varies from
black (no current) to white (maximum
current). 
Wire: used to close
connections.
Switch: can be opened and closed.Some components need are
polarised and thus have a positive and a negative side.
The direction can be set by choosing "+ down/right" or "+ up/left" of the "Direction" list item. The following
direction dependent components can be added:
Battery: value entered in V.
General
Voltage source:
its function prescription (in V) can be entered
next to the source button and it default value is
"sin(t*2*pi*f)". Use "t" as
time variable, "f" as frequency
variable and "p" as period variable.
The frequency can be entered in the text field
below.
Current
Source: value
entered in A.
Oscilloscope: simulation of a
one-beam-oscilloscope. A window with the view on
the particular oscilloscope can be opened by
selecting the "Display Oscilloscope"
option of the popup menu when you click the right
mouse button on the oscilloscope icon in the
circuit.
Voltmeter: simulation of a digital
voltmeter. Use the "Display Voltmeter"
option of the right-mouse-button popup menu.
Ampèremeter: simulation of a digital
ampèremeter. Use the "Display
Ampèremeter" option of the
right-mouse-button popup menu.The "Calculate" button is recalculating data. A number of "Step #" data points is calculated iteratively with a step size of "Step (s)". So the step size is entered in seconds (default is 1e-6 s).
The "Start/Pause" button and the "Reset" button are used when a real time clock is necessary. This is in situations with slow varying sources or the displaying of voltage or current graphs. The number of frames per second = 1 / (10 * step size). This is real time up to step sizes of 0.01s.
You can move a component
to another position by using "drag and drop".
Other actions are available as options of the popup menu
when you click the right mouse button on the oscilloscope
icon in the circuit. The possible options are only
enabled if it is relevant:
