HP 8590D spectrum analyzer CRT repair attempt

Well, the CRT of HP 8590D spectrum analyzer has been malfunctioned for a few months, a while before i was trying to hook up an external monitor to the machine, hope that i can still make use of this machine for a little while more, however i found this way inconvenient because the context button next to the original screen is far away to the external monitor and I also have to turn on the external monitor and video converter whenever i want to use the spectrum analyzer.
As I know the CRT is actually working quite independently to the spectrum analyzer core, i hope that i can open up the analyzer to check if there are some burnt component to replace or some tuning knob i can adjust so to save back the CRT.
May be it's time to start this exploration journey.

This CRT have been looking like this for a few months, too bad.

Amazing looking, what a sophisticated high tech stuff in 90s, 

as a conventional electronics testing instrument design, it's heavy but, not difficult to take off the cover. As I expected the internal of the machine is highly modularized.

CRT, mixer and various of RF modules are shown, many SMB connectors, RF modules are heavy shielded and connected with semi-rigid cables, the CRT shielding could not be open, may be need to tear apart more module before i can take out the CRT.

The A5 second converter module, and a stuff in the middle of a rigid cable looks like common mode filter.

The bottom side contains an unshielded logic board, may be it's the computer, (90s computer)

Marking on the RF modules shows "LOG AMPL", "BW FILTER", "AMPLITUDE CONTROL" and "THIRD CONVERTER", exciting!

Carefully removed the front cover and power supply module, so the CRT could be extract out.

The extracted cute looking CRT, shielding was removed. I can see some knob showing "Vertical Line", "Horizontal line" and so, may be I could try to adjust these knob.

There we go! after tuning the "Vertical line" knob, the screen is backed to normal. I could also tuning the "Vertical size" knob to make the graphics fully using the whole screen size.

Reassemble the stuff back to the position.

It looks better than before, say goodbye to the external monitor.