Speed sensor connections are not supported by Vieta.
You can still ride with a "classic" non-smart trainer by selecting "Ride at Original Speed" option on the connection screen before starting a ride. This will lock the video speed into the original ride length and speed, with no variation linked to your pedalling. This mode enables you to still enjoy the rides and scenery without a smart trainer.
Vieta was built around delivering the best possible ride experience, with next generation video quality and a fully interactive, immersive feel during your ride. This experience with super smooth automatic gradient changes can only be delivered when connected to a compatible smart trainer or smart bike. We do recommend this type of setup.
For the best possible Vieta experience you will need either a smart trainer, smart bike, or Bluetooth powermeter.