Have you moved the 276c any great distance (100's km's ??) from where you last had sat fix?
If u have then I suggest you try going to: "menu" / "New Location" and then 'Use Map" rather than letting the GPS try to find the sats automatically
I find it works for me
I am new to this site but a long time user(3+ years) of this 276C: This morning the unit will not acquire any sats. I removed the external battery, let it stand for over 20 min. and pressed all buttons but that did not work. After a while it will give the message of if I want to go to Simulator, etc.
I would appreciate anyone pointing me in the right direction to fix this problem, and to get more out of this site.