Analog Circuit Tool - User Guide

This application lets you place circuit parts on a grid, connect them with powerlines, edit electrical properties, and run a simple DC or AC simulation with live value overlays.

Basic Workflow

1. Choose a part type from the top toolbar.
2. Click the canvas to place the selected part on the grid.
3. Choose Powerline, then click from one terminal or grid point to another to draw wires.
4. Use Ctrl + left-click on hollow contact markers or wire crossings to make electrical connections.
5. Select a part or wire and use Edit to change its properties.
6. Enable Run to start the simulation and show calculated values.

Top Toolbar

Left Toolbar

• Select: Select parts or wires on the canvas.
• Rotate: Rotate the selected component by 90 degrees.
• Edit: Open the properties dialog for the selected item.
• Delete: Remove the selected item.
• Cancel: Cancel current drawing, dragging, or selection state.
• Clear: Remove the whole circuit after confirmation.
• Circuit: Open the circuit JSON dialog for copying, editing, or loading circuit data.
• Reset: Stop the simulation, clear simulation values, and reset broken items and fuses.

Placement And Editing

• Enable Vertical before placing a component to place it vertically.
• Drag selected components to move them on the grid.
• Use R to rotate the selected component.
• Use E to edit the selected item.
• Use Delete or Backspace to remove the selected item.
• Use Escape to cancel the current action or close dialogs.

Connecting Powerlines

Wire endpoints that land on the same grid point connect automatically. Other possible contacts appear as hollow markers.

• Use Ctrl + left-click on a hollow square at a component terminal to connect that terminal to a wire.
• Use Ctrl + left-click on a hollow square at a wire end touching another wire to connect those wires.
• Use Ctrl + left-click on a hollow marker at a wire crossing to connect the crossing into a filled junction.
• Use Ctrl + left-click on an existing filled marker to disconnect it.

Properties

The Properties checkbox displays compact property labels next to items. The Edit button opens numeric fields for the selected item.

• Sources: voltage, internal resistance, rated power, and AC frequency for AC sources.
• Consumers: resistance and rated power.
• Switches: closed-path resistance and rated power.
• Wires: conductor resistance, cross-section area, and rated power.
• Fuses: rated current, multiplier, and reaction time in milliseconds.

Simulation

• Run: Starts or stops the simulation. Editing tools are disabled while the simulation is running.
• Values: Shows voltage, current, resistance, and power overlays for components and wires.
• Trace: Highlights powerlines that currently carry current.
• Grid length (mm): Defines the real-world length represented by one grid step. This affects wire resistance.
• Milliseconds: Sets how long the app waits between simulation calculations.
• Resolution (Deg): Sets the AC phase step. For AC, the first calculation uses vpeak * sin(1 * resolution), the next uses vpeak * sin(2 * resolution), then vpeak * sin(3 * resolution), and so on.
• History: Sets how many calculation frames are kept for the small value graphs. The default is 1000 frames.

Circuit JSON

The Circuit button opens the current circuit as JSON. You can copy it for storage, paste previously saved JSON back into the dialog, and press Ok to load it.

The JSON stores components, wires, connection markers, and the next internal ID. Simulation history is not saved.

Troubleshooting

• If values stay at zero, check that source terminals and wires are actually connected by filled markers.
• If a component stops conducting, it may be marked broken because its rated power was exceeded. Use Reset to clear broken states.
• If a fuse opens, use Reset or Ctrl + left-click the fuse while editing is available to close it again.
• If AC changes too slowly or too quickly, adjust Milliseconds and Resolution (Deg).