We used to use a JL Cooper sync box but I don't think they're available any longer. It generated timecode you stuck on a track on the analogue machine then it synced the ADAT to that.
You will need some type of controller to lock the ADATs to SMPTE. Stripe SMPTE to a track on your Analog tape machine and feed it to back to the ADAT controller. An Alesis BRC will do this, so will the Alesis AI-2 (but it's a clusterF*** to set up). JL Copper Datamaster would also do this and there may be others.