Help S3 will not connect to wireless repeater


All, just set up a wireless repeater, works fine with Galaxy Grand and laptop, the problem is it will not connect to S3, it picks up the signal, then drops and continues to scan and keeps repeating the process. I can however still connect downstairs directly to wireless router????

I have tried turning off all other wireless devices and only keeping the S3 on, numerous reboots etc, all out of ideas

Any pointers please? Thanks in advance.