can i connect a wifi extender to my apple time capsule? i have a new Netgear AC750 extender and cannot connect it to my wifi. is this compatible?

".....are they compatible?"

Probably not, since Apple uses proprietary software for their "extend a wireless network" feature on the AirPorts......which is designed to only allow an Apple device to wirelessly "extend" the signal from another Apple device.

I don't have the exact Netgear AC750 model here that you have, but I have tried other Netgear extenders over the years, and none of them have really been compatible an Apple router to wirelessly extend a network.

If is not too late, return the Netgear product for an AirPort Express.....which can be set up to wirelessly extend the Time Capsule network in a matter of minutes.

What is the exact model of the netgear wireless repeater??

Repeaters should work in universal repeater mode.. But you need to have a wireless name in the Airport that is short, no spaces and pure alphanumerics. Password should follow the same rules but can be longer.

Also if you are trying to extend the 5ghz and the apple router has chosen a DFS channel it may not work.

I do not recommend this setup.. having run something similar for a while it is issue prone to say the least. It also slows the network drastically.. as any repeater system does even using apple routers.

Bob is quite right that it is much better and easier to use another airport.. the express is slow so be aware that if you want to extend AC wireless you really need an airport extreme.