Sorry to be picky, but I thought Secondary Surveillance Radar was actually to enable ATC to cut out primary radar returns, getting rid of all ground clutter and returns, and enable them to get a picture which only includes the returns sent from aircraft when they are interrogated by the secondary radar pulse? Also I was told that it's mode C which carries the height information from the encoding altimeter, enabling ATC to get a height readout on the aircraft and enabling them to get good vertical separation. In the old days before Mode C and using only primary radar we still used to get vectors for an ILS. You merely flew at the height designated by ATC but they had no visual presentation of it on their radar screens except for GCA approaches to military airfields.
Back to the original thread, Port Harcourt is improved in that it has a working VOR/ILS/DME approach after many years of occasional serviceability, and the NDB has been re-installed, but the level of professionalism of the actual controllers is generally pretty dreadful, notwithstanding the fact that they have no radar and it's all procedural approaches. It may be to do with the fact that as a 'relatively' busy airfield for Nigeria, a lot of ATC personnel are posted there direct from training and are still basically under training. Put many of these guys in a busy European or North American environment and there would be chaos, but maybe some cross-postings and cross-training would be beneficial. Port Harcourt urgently needs a serviceable SSR radar installation if it is to coipe with the increased levels of traffic you are implying in another of your postings.
Things are undoubtedly improving, but the rate of improvement needs to be considerably increased.