Can I use the 815xxA Series optical heads with the 81618A / 81619A interface modules?

The 815xxA Optical Heads can NOT be used with the 81618A/81619A interface modules. Only the 81533B can be used with the 815xxA series optical heads.

However, the 81533B interface module with an 815xxA series optical head will operate in the 8163 and 8164 mainframes but NOT in the 8166 mainframe.