a receiver module disposed within the receiver module housing, the receiver module having an optical to electrical converter for converting {HEAD ~ optical signals} into {TAIL ~ electrical signals}, wherein at least a portion of the optical signal propagating along the tube toward the second end of the tube passes out of the second end of the tube and is optically coupled onto the OEC 
into
a receiver module disposed within the receiver module housing , the receiver module having an optical to electrical converter for converting { HEAD ~ optical signals } into { TAIL ~ electrical signals } , wherein at least a portion of the optical signal propagating along the tube toward the second end of the tube passes out of the second end of the tube and is optically coupled onto the OEC
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH