Electron imaging produces only horizontal lines

[orlandin]

Hello, all!

I am having an interesting hiccup where all of my electron images in PFE are coming out as horizontal lines of varying greyscale intensities. I've tried closing PFE and opening again to reconnect to our 8200 with no success, as well as turning the detectors themselves on and off on the Unix side. Is there a undocumented but common sense thing that I'm missing, like telling PFE to only be in spot or scan mode? I recall this happening once before too - it's not very common, but I can't for the life of me remember what gets things talking to each other properly again.

Best,

Phil

[Probe321]

Phil
Hopefully you have the problem resolved before you read this.  Have you tried shutting off all the electronics on the probe and PFE computer and restarting aka the old cold boot.  If this does not work try checking the cables the video cable may have failed. Good luck
Keith

[Nicholas Ritchie]

The signal looks like a linescan which suggests that the Y-scan is fine but the X-scan is failing.

It could be that the X-scan signal is
  1) not being generated on the scan generator in the PC (use a oscilloscope to check the output of the scan generator)
  2) is not making it to the SEM/microprobe X scan input (check the cabling)
  3) failing inside the SEM
    3a) rotation compensation electronics (does the signal change with scan rotation?)
    3b) scan coil amplifiers
    3c) scan coil short or break

You might try
  * reversing the X- and Y- scan outputs from the PC - what happens to the image?
  * seeing what happens when you change scan rotation - what happens to the image?
  * change mag ...

It appears that the Y-scan signal is fine (assuming that the sample has a line-scan topography like that in the image.)

[orlandin]

Good morning, Keith and Nicholas!

Thank you so much for this advice! This is not a comprehensive answer, but performing an OPE reset and rebooting both the JEOL and PFE computers resolves this problem. Nicholas, the next time this happens I will try some of your suggestions and report back here in case that helps to learn something interesting about the way these two (three?) computers talk to each other.

Best,

Phil

[Probeman]

..., but performing an OPE reset and rebooting both the JEOL and PFE computers resolves this problem.

Or as they say in IT: "Did you try turning it off and on again"?