I'm thinking of buying this Admiral

[bandersen]

Originally Posted by MadMan

...So what you're saying is... I did it right without even knowing what I was doing? Score!

Also I have no way of knowing which direction the magnet is supposed to be, other than the way that I found it. It has no arrow.

Black to the base - it's on backwards. Also the linearity and width slugs have a very subtle effect and are meant for really fine tuning the picture.

[EdKozk2]

MadMan,
After you reverse the ion trap and reset it, you may find an improvement in the focus. Otherwise everything looks good . Some of the horizontal linearity issues and slight phase shift you mention seem to be inherently common with these Admiral sets. The last three Admiral sets I repaired had some of the same issues.
I just got an Admiral 12X12 this past weekend, won't get to it till next year.
Did your set come with a metal rear cover and metal underside shield ?
The rear cover that came with mine looks it may fit more than one model.
Ed

[MadMan]

Originally Posted by EdKozk2

Did your set come with a metal rear cover and metal underside shield ?
The rear cover that came with mine looks it may fit more than one model.
Ed

Yup, I has cover ^_^ but ty.

Originally Posted by bandersen

Black to the base - it's on backwards.

Ah. Thanks. Well. It was like that, so not my fault. Actually now it makes sense - blue for electrons, black for the base.

I flipped it around and it seems to have made no difference in the clarity of the image. Perhaps I should readjust horizontal. However, I had to shove it all the way forward on the neck, touching the focus coil. Which I might move it back a bit so the focus can be adjusted, but hey on the plus side, the focus coil gets to be a lot more straight now.

Idk, how awful would it be to put it on backwards? I'm concerned that in the future if the focus coil adjuster gets bumped, it'll snap the crt neck, what with the magnet butting up against the coil.

[jr_tech]

"Turning the brightness down improves the clarity of the image, but even with the lights off in the room, the image would be too dark (and have too poor a contrast) at a level of brightness that produces a clear enough image. On the other hand, with the brightness all the way up, though the image is blurry, the screen is pretty damn bright. So... the crt is good, I guess?"

Pretty good indication of a weak CRT... yes you can turn up the grid drive and get a fairly bright image but not good focus, as the "sweet spot" (center) of the cathode is depleted... when you turn up the drive, you are drawing more electrons from off center areas, this is not conducive to good focus. Hopefully, the cathode will improve as you run it longer, or perhaps try to re-activate by running the heater at increased voltage (like 7 to 8 volts) for a few hours.

jr

[MadMan]

Originally Posted by jr_tech

Pretty good indication of a weak CRT...

Well... big surprise, right? I had it running the other day and it seemed better, but like I said, it really seems to get worse as the set warms up, but I'm not 100% sure about that. I'm still going to inspect the focus circuit anyway. Plus I still got that slight shadow, but maybe that's not related.