Autohelm ST50 change to ST70 ??
 

I have on flybridge panel 2 pcs ST50 displays (Speed and Depth) and ST7000 autopilot. The old ST50 units starts to have some moisture problems and I would like to replace them with one new ST70 multidata display. I have understood, that even the 1998 yearmodel Autohelm ST50 units are using SeaTalk bus communication and the new ST70 units should communicate with Ray's new SeaTalk-ng but also with old SeaTalk protocol and also there are available SeaTalk-SeaTalk-ng convertors. So my question is, if it should be possible to use the old sensor and bus cable and just plug the old SeaTalk to ST-STng convertor and then with ST-STng connection cable from the convertor to one ST70 display? Which then should show me both depth and speed data!?? Has anyone tried to do this?