Sometimes ( like today ) the dropout lasts less than hour , other times I give up and try next day and it's been sorted.
My father who is also with Exetel had the same issue today although he has his external antenna pointed at a different tower to me , and my mobile phone is with Optus and I had no trouble making a phone call using the same tower as my internet connection , therefore I'm ruling out a transmission tower problem .
The GUI indicates several bars of reception , WCDMA , so that's not and never has been an issue.
Today was particularly annoying for me as I was 4 minutes away from placing an ebay bid on a ride-on mower I wanted , lost connection for about 50 minutes , auction finished

Could one of the staff ( input from others also welcome ) shed any insight on why these dropouts occur , and are they at Exetels' end or with Optus ?
Cheers all.