7280,showing"Input Overload"without input

From: Nanjing China
email: macf@nari-relays.com
Model: 7280
Date: 12 Aug 2005

Comments

Now I have a problem with 7280:After turning on the instrument,it appears "AMETEK"then directly appears "main display" without appearing the "main menu 1"! The most important problem is, at left top of the screen ,the "Input overload" flashing for all the time either with signal and reference or without,even though I change the sensitivity from the minimum to the maximum! And resetting the instrment cannot solve this problem! Please tell me if it is broken! Thank you!