does anyone else have a problem with their wifi connection dropping on a new imac with mountain lion installed

i am having problems with my imac, it seems to drop the wifi connection within 1/2 an hour its as if someone is literally pushing a button OFF!!!

Has anyone else had this problem???

I have many other devices on my network that dont have any issues

I have now hard wired to my network to see what happens, currently all seems ok

Thanks for reading

Mark