Tektronix 4051 repair.

[Mattis Lind]

I took a look at the Tektronix 4051 that we got a few years back. After
checking the PSU I turned it on and it seemed to start up fine. The machine
responded well to the keypresses but it was hardly readable on the screen.

Anyone that can give advice on what is wrong and how to deal with it. The
text on the screen is very faint and many characters are scrambled as if
the beam was moving when the points where plotted. When typing there is a
flash of the beam which is then stored as the scrambled text.

http://i.imgur.com/iQhQW67.jpg

It probably reads "SYNTAX ERROR" something on the screen.

My experience with DVST device is minimal. I used an old Philips storage
oscilloscope many years ago but I don't remember the screen to be this dull.

It seems like the storage system is not at full output. Unfortunately I am
not getting a good understanding on how the DVST system works from reading
the service manual. What is the purpose of the timers for cursor and
character intensity?

I am about to check all the voltages related to the display mentioned in
the calibration section of the manual, but just in case someone directly
recognize what kind of problem there is I would be much interested.

/Mattis