Old Router As Ap

Hi all.
I had a weak spot in a bedroom so I decided to use a router I had to extend the network.
It's a D'Link DIR 615.
It has a AP setting which I checked, once checked all other options greyed out, and I saved.
As far as I'm aware, once checked it should automatically act as an AP.
When I searched for networks I could see my original network plus a unsecured network called D'Link.
I reset the D'Link and this time I changed the SSID to that of the original network and entered the same password then checked the AP box.
This time there was only one SSID showing and it seems to work with the signal improving within a few seconds. I'm assuming that is as it changes over.
From what I've read I should be able to access each router individually to make changes.
Or is that only when you manually set up an AP?
If I should be able to access the second AP, where do I find the ip address?
I've run ipconfig but only see router 1.
Cheers