ipad connect to airport extreme

I have just connected my AirPort Extreme as my Wireless Network Base Station. it is updated to version 7.5.2

My iMac connects to the AP Extreme and connects to the internet perfectly well.

When I try to connect my iPad (v1) to the AR Extreme it connects but gets no connections to the internet. The AP Extreme is reporting 2 Wireless clients connected.

Radio Mode : 802.11a/n - 802.11b/g

Radio Channel Selection (Manual)

44 (5 GHz), 11 (2.4 GHz)

Wireless Security is WPA2 Personal.

i've enabled the 5 GHz option but this doesn't work either.

Multicast Rate : High

Transmit Power : 100%

WPA Group Key Timeout: 10

Use wide Channels (selected)

i've tried DHCP on the iPad, but the selections it makes I don't recognise

IP Address : 169.254.74.62

Subnet Mask : 255.255.0.0

Router : blank

DNS : 194.168.8.100

I've tried manually configuring the IP Address as Static, but this doesn't work either.

Does anyone have any ideas what I can do or try?

Thanks