Re: Mechanism of CRT Double Peaking
I don't see the rationale behind this. With rising grid voltage larger ringsYep, as I mentioned... my rational may be (and probably is) flawed.
Back when I was still struggling with that 464 and romancing the chance there could be some level of recovery to that CRT, I read a lot of things in a lot of places... In many of them I encountered widespread use of the term "Double Peaking" but in none of them I found explanation about the mechanism that originates the behavior.
I agree that by my own rational, the intensity should always increase (maybe not at an even, or linear fashion, but always increase).
BTW the potentials discussion in the CRT Circuit Concepts book seemsYou may be right... I`m not familiar with the term "space charge".
The Tekscopes issueGassy tubes or worn cathode... Well... In my way of seeing it, apart from tubes (or CRTs) that have a manufacturing defect or a crack, I tend to generalize that gases develop on a tube as they wear out... so I think it's kind of difficult to tell apart which of the abnormal behaviors are due to the presence of gas, or from the cathode itself being worn out so, I plead guilty for using "Cathode Wear" for everything.
A little side comment... with so many people in this group with access to things as exquisite as Electron Microscopes, high vacuum pumps and etc... I wonder how come that nobody has come with means to open the worn out tubes, replace or recoat the cathodes, and seal them back again.
I see there are still some plants that do this kind of thing for specialized tubes...