> For the complete documentation index, see [llms.txt](https://support.4cast.world/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.4cast.world/archive-v12-userguide/4.-ltc-timecode-setup/ltc-timecode-setup.md).

# LTC Timecode Setup

Linear Timecode (LTC) allows you to trigger video and lighting clips using an LTC (SMPTE) audio source.

The MVP listens for the audio signal via its rear input port and fires specific clips when the incoming timecode matches your Timecode Trigger.

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### 1. Hardware Connection

1. Source: Connect your timecode source into the Pink 1/8" (3.5mm) **IN** port on the rear of the MVP.

<figure><img src="https://972130380-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FJy0o1OGq5vpGIjXyRxmH%2Fuploads%2FVCgz2dQ0QPL1BjtlTdjt%2Fimage.png?alt=media&amp;token=80be41f6-061c-4372-a618-d81a1dbc38aa" alt="" width="563"><figcaption></figcaption></figure>

***

### 2. Signal Verification (The Input Monitor)

Before programming triggers, you must ensure the MVP is receiving a clear signal.

1. Navigate to the MVP's **Dashboard** page.
2. Start playback on your LTC source.
3. Check the **LTC Counter**: You should see the numbers running rapidly (HH:MM:SS:FF).

<figure><img src="https://972130380-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FJy0o1OGq5vpGIjXyRxmH%2Fuploads%2FVjxYZcn6hPDPYyAJLl3O%2Fimage.png?alt=media&amp;token=5916bcc6-6a06-44d5-851b-4a853b30d9a0" alt="" width="416"><figcaption></figcaption></figure>

Troubleshooting Signal Levels:

* If the counter is frozen or erratic: The audio volume is likely too low or too loud (clipping).
* Fix: Adjust the output volume on your source device up or down until the MVP's LTC Counter runs smoothly and consistently.

***

### 3. Creating Triggers

Once your signal is verified, go to the **LTC** tab in the left sidebar.

<figure><img src="https://972130380-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FJy0o1OGq5vpGIjXyRxmH%2Fuploads%2FRdtvdqmhD1qhJ8ydSlYu%2Fimage.png?alt=media&amp;token=8f6e9cb1-3919-441a-9dbe-7f921a0af98e" alt=""><figcaption></figcaption></figure>

Add New Timecode Trigger

1. Click the toggle switch to enable **EDIT MODE** on the top right.
2. Click the blue **ADD NEW TIMECODE TRIGGER** button.
3. **Select Type**: Choose between **VIDEO TRIGGER** or **LIGHTING TRIGGER**.
4. **Set the Time**: Enter the exact HH (Hours), MM (Minutes), SS (Seconds), and FF (Frames) for the trigger.
5. **Select your Media**: Choose the specific video file or lighting clip from the dropdown menu.
6. **Save**: Click the **SAVE** button.

<figure><img src="https://972130380-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FJy0o1OGq5vpGIjXyRxmH%2Fuploads%2F7t996kOpFBieUaR3B7dk%2Fimage.png?alt=media&amp;token=915ba303-29fd-4c91-86dc-fc817d4eb4f0" alt="" width="433"><figcaption></figcaption></figure>

Repeat this process to add all of your LTC triggers.

#### Managing Triggers

* **Edit**: Click the Pencil Icon next to any trigger to change its settings.
* **Delete**: Click the Trash Can icon to remove a trigger.
* **Sort**: Triggers are automatically sorted chronologically.

***

Note that the MVP uses LTC as a Start Trigger, not for continuous synchronization.

* Behavior: When the incoming timecode matches the Timecode Trigger values (e.g., `00:01:30:00`), the MVP simply presses "Play" on the assigned clip.
* No Scrubbing: The clip plays at its normal speed. It does not slow down, speed up, or scrub backward if the external timecode changes speed. It purely listens for the specific "Go" frame.