re:WG failures

In message "WG failures", aek (Al Kossow) writes:

> Zonn had tried bypassing the regulator completely on an WG, with some
> problems with vector stablity. One thing that was suggested is putting
> a pecision voltage reference at the base of the current source (Q602/702)
> to improve its stability if you were going to run it from an unregulated
> supply. Or, put 7824's and 7924 regulators in in place of the 3.3 ohm
> resistors and drive just the deflection transistors unregulated.
>

There's been a lot of talk about stability lately. I've assumed this has
meant the display's ability to draw something in the same spot repeatedly.
For example, the copyright in the Tempest attract mode. I assume this be-
cause that is the type of instability I've observed in these displays.

It seems a lot of attention is currently on the deflection section of the
display, but HV ripple and regulation seem to have a lot to do with image
stability (as defined above) as well.

Has anyone else found that to be the case?

Does anyone know what the impact of poor LV regulation is on image stabil-
ity versus poor HV regulation? I've observed stability problems (in a WG)
while the LV is fairly well behaved, only to find ripple on B+.

Cheers,
Mark
Received on Wed Sep 3 16:12:02 1997