Nebula Cosmos Laser 4K projector supports HDMI connection. If there is no signal when connecting an external device via an HDMI interface, you can try the following solutions.

1. Use a different HDMI cable.

2. Connect your Nebula Cosmos Laser 4K with another device with your HDMI cable.

3. Disconnect from your projector and try connecting your device with your TV via HDMI.

4. Adjust the HDMI output resolution/Hz of the connected device to match the Nebula Cosmos Laser 4K projector.

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