The system 4 in which {TAIL ~ the means} for providing {HEAD ~ a test signal} is a video signal storage and retrieval system 
The system 4 in which { TAIL ~ the means } for providing { HEAD ~ a test signal } is a video signal storage and retrieval system
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH