This has me baffled, I was given a Tek 2215 a few months back, this was like new and had been sat in storage for 30 odd years.
It was all working perfectly but today I noticed it flickering horizontally slightly which was annoying me as I assumed it was an issue with what I was working on!
I've had it in pieces and gone through everything, all voltages are correct and within spec. This issue is present on both inputs I suspect its an issue with the Horizontal deflection circuitry.
However I do not have access to another scope at the moment so it's a bit of a chicken and egg situation. I have a feeling the input section and controls are all okay, I did check it all over for dry joints and given it a good tap and wiggle everywhere, the V/H wires are fine on the CRT.
Hoping this is a common or known issue with this, I know they are not the best scopes but it suits my needs and the CRT had zero hours on it, so hoping to keep this going.
Excuse the poor video, but just uploaded this to YouTube to give a rough idea of what's going on: