You should try this
https://www.bhphotovideo.com/c/product/880882-REG/Neutrik_NADITBNC_MX_Digital_Impedance_Transformer....
with that you can put the adaptor into the back of your 866 and a standard coxial cable from node to back of that adaptor.
https://www.bhphotovideo.com/c/product/880882-REG/Neutrik_NADITBNC_MX_Digital_Impedance_Transformer....
with that you can put the adaptor into the back of your 866 and a standard coxial cable from node to back of that adaptor.