Variable Copper Bulb Signal
Variable Copper Bulb Signal changes the comparator output of copper bulbs, so a bulb's redstone signal follows its oxidation state and light level.
What it does
Copper bulbs in vanilla give light at different levels depending on how far they have oxidized. This mod links that light level to the redstone signal a comparator reads from the bulb, so a comparator placed beside a bulb reports a strength that matches its oxidation state. Builders can use the copper stages as a built-in signal source, for example to pass a graded value through a contraption without extra blocks.
The mod runs on the server only, so players join without installing anything. It requires Fabric API on the Fabric loader. The code is open source under the MIT License, and files are published for Fabric, Forge, NeoForge and Quilt, with the latest build 1.0.0 for 1.21.11 dated 2026-07-04. Builds cover 1.21 – 26.1.2 across 15 release versions, and snapshot builds are not part of the listing.
Key features
Comparator output from copper bulbs
A comparator reading a copper bulb receives a signal strength tied to the bulb's oxidation level.
Light level as signal
The redstone value follows the same light level steps the bulb already emits, so the two stay in step.
Signal from oxidation state
As a bulb oxidizes, its comparator output changes, letting a circuit read copper age as a number.
Server-side operation
Only the server needs the mod, and clients connect without installing it.
Gallery
Compatibility
Latest build for each game version and loader.
26.x3 of 3 versions with builds
1.21.x12 of 12 versions with builds
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Who it’s for: Redstone builders and server owners who want copper bulbs to act as a signal source. Players who only play single-player on a client without a server need not install anything extra beyond the loader.
How it compares
Sulfur Oxidizes Copper is an MIT-licensed mod for Fabric, Forge, NeoForge and Quilt, built for 26.2 – 26.3, and it needs the server while clients remain optional. Remote Lights is an MIT-licensed mod across Fabric, Forge, NeoForge and Quilt, covering 1.21.2 – 26.1.2, and it is also server required with client optional. AutoOxidize is a client-side only Fabric mod under the MIT License for 1.21 – 1.21.5, so it does not change what a server reports.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Variable Copper Bulb Signal | Fabric, Forge, NeoForge and Quilt | 1.21 – 26.1.2 | Server-side only | 2026-07-04 |
| Sulfur Oxidizes Copper | Fabric, Forge, NeoForge and Quilt | 26.2 – 26.3 | Server required, client optional | 2026-09-16 |
| Remote Lights | Fabric, Forge, NeoForge and Quilt | 1.21.2 – 26.1.2 | Server required, client optional | 2025-03-13 |
| AutoOxidize | Fabric | 1.21 – 1.21.5 | Client-side only | 2025-03-27 |
Questions
Does Variable Copper Bulb Signal need Fabric API?
Do players need to install the mod?
Which game versions does it cover?
In the catalog
Variable Copper Bulb Signal is one of 29,952 Game mechanics mods on ModsFinder, and one of 19,630 Game mechanics mods for Fabric. 15,189 mods support Minecraft 26.1.2.
More from Strange-Quark
Similar mods
What the author says
Copper bulbs have different light levels based on its oxidation state, but why limit it to only light levels? ### This mod enhances the functionality of copper bulbs by changing the comparator output, i.e., the redstone signal strength, to match the light level of its oxidation state.
Official listing
- Modrinth page
- modrinth.com/mod/variable-copper-bulb-signal
- Owner
- Strange-Quark
- Published
- 2024-07-10
- Updated on Modrinth
- 2026-07-04
- Facts verified
- 2026-10-15