If you have a camera with Timecode & Genlock input, you can make the recorder (in my case a Mixpre10-II) the master and feed Timecode Out to a UltraSync One (Master). On the camera side, a Slave UltraSync One can provide both Timecode and Genlock to the camera. I use this setup and it works great - no drift with 1hr+ long continuous recordings. Very compact and low cost solution (assuming you need Timecode sent to multiple cameras anyway).