The scope was working great... then I moved.
When turned it on after unpacking I noticed that sweep only showed only in the left side of the display. Could move it a bit towards the right (to the 1st major division to right of center) with the Position adjustment, at which point the waveform got a bit compressed. I could also move it off screen to the left for a couple of major divisions.
I then opened the scope up (I have a scanned service manual) and adjusted the Geometry (R870) to center the waveform. With a 1 kHz sine input at , I get a maximum display width about 1.5 major divisions off the center to each side. I can move the display fine left and right with the Position adjustment.
I then tried adjusting the A GAIN (R740) (based on this https://goo.gl/k5iZZJ ) which allowed for a bit more (maybe 1 or 2 minor divisions) display.
Then I noticed that pressure on the bottom of the board or deforming/twisting the scopes frame will restore the normal width display (now out of calibration thanks to my trimming), so I suspect I have a bad solder joint somewhere (I suspect the high voltage system but I have a great deal of respect for 7kV)
Before I go through a wild goose chase, anyone have an idea what I can narrow it down to?
TIA, Dre
When turned it on after unpacking I noticed that sweep only showed only in the left side of the display. Could move it a bit towards the right (to the 1st major division to right of center) with the Position adjustment, at which point the waveform got a bit compressed. I could also move it off screen to the left for a couple of major divisions.
I then opened the scope up (I have a scanned service manual) and adjusted the Geometry (R870) to center the waveform. With a 1 kHz sine input at , I get a maximum display width about 1.5 major divisions off the center to each side. I can move the display fine left and right with the Position adjustment.
I then tried adjusting the A GAIN (R740) (based on this https://goo.gl/k5iZZJ ) which allowed for a bit more (maybe 1 or 2 minor divisions) display.
Then I noticed that pressure on the bottom of the board or deforming/twisting the scopes frame will restore the normal width display (now out of calibration thanks to my trimming), so I suspect I have a bad solder joint somewhere (I suspect the high voltage system but I have a great deal of respect for 7kV)
Before I go through a wild goose chase, anyone have an idea what I can narrow it down to?
TIA, Dre