Circuit Editor Basic Operations Guide for uSimmics (formerly QucsStudio) [2026]

uSimmics (formerly QucsStudio) is a powerful software platform for advanced circuit simulation. To work efficiently in the circuit editor, it is essential to understand mouse operations, keyboard shortcuts, and the correct use of each editing mode.

This article provides a mode-by-mode and function-by-function reference of all available operations in the uSimmics (formerly QucsStudio) circuit editor, along with practical tips to improve your workflow.

What You Will Learn
General Operations
Selection Mode
Component Insertion Mode
Wire Mode
Paste Mode
File Operations in the Content Tab
Keyboard Shortcuts
Tips for Efficient Operation
Summary
Related Articles

What You Will Learn

An overview of each operation mode in the uSimmics (formerly QucsStudio) circuit editor
How to use mouse operations (click, scroll wheel, right-click)
A complete list of keyboard shortcuts
File management operations in the Content tab
Practical tips for efficient schematic creation

General Operations

Operation	Description
Mouse wheel	Scroll the circuit editor view vertically
Shift + Mouse wheel	Scroll horizontally. Also works while moving a component
Ctrl + Mouse wheel	Zoom in or out
Middle button (wheel click)	Toggle component activation/deactivation
Drag and drop a file	Open as a schematic or data display file

Selection Mode

This mode is used to select and move components and wires.

Operation	Description
Left click	Select the element under the cursor. If multiple elements overlap, click repeatedly to cycle through them. Hold and drag to move a component. Hold Shift while dragging for fine-grained positioning
Ctrl + Left click	Add elements to the current selection. Click an already-selected element to deselect it
Right click	Select a single straight wire segment
Right double-click	Open the properties dialog for the element

Component Insertion Mode

This mode is used to place new components onto the schematic.

Operation	Description
Left click	Place the component, diagram, or shape on the schematic
Right click	Rotate the component by 90°
Middle button (wheel click)	Mirror (flip) the component

Practical tip: Set the orientation of a component before placing it with a left click. This eliminates the need to rotate it afterward.

Wire Mode

This mode is used to connect components with wires.

Operation	Description
Left button	Set the start or end point of a wire
Right button	Toggle the corner direction (horizontal-first or vertical-first)
Right double-click	End the wire without connecting to a port or existing wire

Practical tip: If a wire bends in an unintended direction, use a right-click to toggle the routing direction. This is especially useful in dense layouts.

Paste Mode

This mode is used to paste components and wires from the clipboard.

Operation	Description
Left button	Paste the clipboard contents onto the schematic
Right button	Rotate the pasted elements

File Operations in the Content Tab

Used for managing files within a project.

Operation	Description
Left click	Select a file
Double-click	Open a file
Right click	Display the file context menu (see items below)

Right-click menu items:

Item	Description
Open	Open the selected file
Info	Display detailed file information
Rename	Rename the file
Delete	Remove the file from the project
Delete Group	Delete related files together (e.g., schematic and data display)

Keyboard Shortcuts

Key	Action
Delete / Backspace	Delete the selected element. If nothing is selected, switch to Delete mode
Enter	Open the properties dialog for the selected element
Arrow keys	Move the selected marker or element. If nothing is selected, scroll the view
Shift + Arrow keys	Change the reference position of the selected marker

Tips for Efficient Operation

Precise component selection: In densely populated areas of a schematic, repeatedly clicking with the left button cycles through overlapping elements, allowing you to select exactly the one you need.

Using keyboard shortcuts: Deleting unwanted elements with Delete and opening property dialogs with Enter are significantly faster than relying solely on mouse navigation. Building these habits will noticeably increase your throughput.

Making zoom a reflex: Mastering Ctrl + Mouse wheel zoom allows you to switch seamlessly between inspecting fine wiring details and reviewing the overall layout.

Summary

The uSimmics (formerly QucsStudio) circuit editor assigns distinct operations to each mode. Mastering these mode-specific interactions enables efficient schematic creation. In particular, the wire corner direction toggle and keyboard shortcuts can dramatically change how quickly you work. Use this reference alongside real design tasks to build fluency.