Although I think the cable is the most likely problem, another
possibility to bear in mind is simply that your antenna might not be
pointing the right way.
It is far more directiional, so you should not be getting all the APs at
the same time.
Thanks for your reply. Could you please suggest a long length alternative for the cable? And I understand it is directional so I have tried to point it in every direction possible with no luck? What should I do?