My 2440 behaved in a similar way after I improperly did the CCD
calibration. Maybe one of those many trimmer potentiometers is bad or
drifted. You need a tunable signal source like an SG503 and lots of
patience to perform that part of the calibration procedure.
On Tue, 20 Nov 2012 16:30:19 -0000, "marjoriehookham"
<marjoriehookham@...> wrote:
Hi,
The symptoms are that the display goes crazy when changing from 100 microsecs timebase to 50 microsecs or above but only when acquiring.
Using Special/ Force DAC to correct the Centring values (CT11/21)brings back a reasonable display. I can see this working on the 4051 chips pin3
however trying to write these to store fails and the old value comes back when TBase is 100microsecs or greater.
I cold start most times I start the scope to have a known base. Lithium Battery is fine, amazing.
I first rebuilt the Low voltage Power supply with new caps. Then all the electrolytic caps on the main board A10.
I am tempted to think that D7 of the data bus is being pulled by the waveform processor bus. Any ideas
Rob ( this is my wifes ID)
David Hess