The used boat I just bought did NOT come with a remote. It's a 2018 model and the previous owner did not get the remote when he bought the boat also used. Duh. Any idea how to calibrate it without one? Tried to Youtube but they all use the remote to do it. I'm sure he never paired the ultrex to the heading sensor, or calibrated the heading sensor, or set up the sensor offset. The spot lock works but is not as accurate as I'd like it to be. PM if you like. Thanks!

You are in a bit of a bind, then. From what I see reading the manuals for the Ultrex and the heading sensor, a remote paired to the particular heading sensor is required for calibration.

To see for yourself, you can download the manuals for both parts (TM + heading sensor) from this page:

Ultrex & Heading Sensor Manuals

Calibration mandates the use of one of the remotes, and that remote must be paired with the heading sensor (via bluetooth). That means you can't simply/easily borrow someone else's remote for a few hours to do it. To pair the set, the heading sensor will have to be removed in order to push the pair button on the bottom. After you return a borrowed remote, its owner would have to remove his heading sensor to get to the button in order to re-pair that BT connection. Too bad the remote was available and passed to each new owner. It looks like the BT remotes go for $180. I'm fairly certain you need the BT capable version for the Ultrex, so don't plan on buying the cheaper non-BT remote.

Thanks Flip...that's what I figured. Dang.