Re: Tektronix 465B Scope - Some problems.
I think the noise voltages on your plates say that your fuzzy trace isn't due to hum, ripple or noise, so I'd start checking the voltages on all the CRT electrodes.
One nasty possibility is internal damage to the CRT due to a bad knock.
Can you see the ghost spot? Set the timebase sweeping the spot across the screen on its slowest range, 0.5s/div and make the spot rather bright. You should see a dim ghost cross the screen at twice the speed of the spot. It is always about twice the distance from the centre that the spot is (and in the same direction) In my 465 it looks like a thick doughnut about 1.75 divisions in diameter.
It's an image created by the post-deflection accelerator screening dome-shaped mesh.
Its presence shows that the electron optics around the mesh are OK.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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