Two little Predicta questions
 

After a recent relapse was cured, my Predicta looks good but has two little issues.

http://antiqueradio.org/art/DorothyWizard.jpg

Issue 1. The horizontal centering and linearity are just a tad off. I've done all I can with the centering control -- it just moves the image in one direction and then goes back the other way if I turn it farther. I can't move the linearity adjuster at all. It's the flat magnet sticking out on an arm to the left.

http://antiqueradio.org/art/Predicta...lLinearity.jpg

I tried to rotate it, which just started rotating the entire yoke. It is tilted with the top end closer to the front, but adjusting by bending the arm seems so peculiar that I hesitate to chance it. What's the secret behind this adjuster?

Issue 2. There is an opaque piece of "stuff" stuck between the cover and the CRT face, so I want to remove the cover.

http://antiqueradio.org/art/PredictaScreenBlotch.jpg

The oval cover clasp seems to be held on with wire hooks at the base, but I can't get them free with a needlenose plier. The clasp is on really tight. If someone has done this before, how did you do it?

http://antiqueradio.org/art/Predicta...CoverClasp.jpg

Thanks!

Phil Nelson

Hi Phil. I've removed the cover from the Princess model which seems to use the same clasp.
I was able to use pliers to unhook the spring. I recall it took a pretty strong pull.
I removed the bolts to free up the steel band holding the plastic cover together.
Then, I removed the arms.

http://farm4.static.flickr.com/3540/...e8df1535c9.jpg http://farm3.static.flickr.com/2792/...a19f3c6053.jpg http://farm3.static.flickr.com/2571/...0d7d767a10.jpg http://farm3.static.flickr.com/2669/...b941468ff8.jpg

Phil, the magnet on the arm on the left should be the centering adjustment, bending it should be the correct method, at least it is on other sets that use it.
Bend it closer to or further away from the bell, straight forward or straight back.

Obviously if it seem to have a lot of resistance to bending than maybe we need to rethink it or get some info from someone who knows for sure.

Hi Phil;
When I worked on my Predicta's, I ran into the same issues that you're now facing. My conclusion about the horz. centering was that the little flat disc magnets used for centering have lost some of their magnetic pull and will never work as well as they did when new. And you're right about the horz. linearity, it's just a matter of bending the arm assembly around to find the "sweet spot". It seems like a real half baked way of doing it, but this whole set kind of leans in that direction.

Like you I also went to battle with that darned difficult to release spring in the neck base. I discovered the easiest way to put the face and band on and take them off is to leave the spring attached in the base and carefully spread the band around the face of the tube cover and slowly work it into place. The spring will give enough to allow the band to go over the little ears. When I remove the face, I go in reverse and pull the band up over the ears and slowly pull it off. It seems to work quite well for me.

I don't know that I've ever seen a 21" Predicta with a picture that is free from some type of geometric distortion (including mine). The smaller 17" sets seem much better.

Good luck.
Bob

Sams says linearity is adjusted "by means of a magnet located to the left of the yoke," but doesn't explain how to manipulate it. If you have to ask . . .

The two centering adjusters seem to work as advertised, so this must be the right adjuster. I'll try bending it and see what happens.

Phil

Predicta spring
 

On reattaching the spring, some "lengthen" the spring by attaching a strong paperclip to it & cutting off as needed If needed, this works great and makes rehooking much easier and is hidden by the bottom trim piece on the swivel base.

My Predicta Princess has the same issues-correcting a horiz. lin. issue on one part of the screen just causes another one somewhere else. This is the only set I have with the adjustment just being a magnet, so maybe that's the best it can do.

I'm still too much of a weakling to get that spring back on, I lengthened mine with a bit of wire, but now the spring is too slack to really do its job.

Thanks, maybe I'll try inching off the cover when I get back to the shop. I don't want to pull the CRT off the cabinet, and there's not much room to fit a pliers in that space. Sounds like removing the spring would just end in tears.

It's weird to have a piece of junk between the cover and picture tube. The tube is very bright, so perhaps it was replaced and the "thing" got in there at that time. Looks like a bit of paper or straw.

The linearity & centering are only a little bit off. I'll see what some bending does. If the answer is "nothing," I can live with it. You only notice it when there's something like film credits that fill most of the screen.

Phil

The dime size magnets rotate to center the picture. They should move easily by hand. The factory used a plastic tool.

Yes, the little centering magnets work OK (up to a point, anyhow). I didn't know that you're supposed to bend the linearity adjuster.

There's often a little interaction between width, horizontal centering & linearity. I'll get as close as I can by fiddling those three, then call it a day. I have a couple of other sets that you can't get perfect in one dimension or another no matter what you do, so you pick the compromise you like best :)

Phil

I'm done. It's as good as anyone could manage without replacing tired adjuster magnets (and who knows if that would really make a difference).

What a piece of work that linearity adjuster is. For the record, bending the whole thing forward or back adjusts horizontal linearity. Twisting it so that one ear is farther forward than the other just deforms vertical linearity on the right side.

It's back in my office where it belongs, playing a movie. I'll ignore the fleck under the cover for now. More urgent projects are crying for attention.

Thanks again for the tips.

Phil

Phil,
I caught the thread a little late, but did you notice if there is a 'width sleeve' on the CRT neck? That's a little sheet of brass mesh or shimstock rolled into a cylinder and fits inside the yoke, and is meant to slide in or out to adjust width. I generally threw the damn things away if width was sufficient without it. If present, it could conceivably cause some wonky issues with linearity etc. Bill(oc)

I'll keep that in mind if I ever have a reason to mess with the yoke. I just removed the back plate from the CRT cover and didn't look closely at the neck.

There's not enough play in the cover band to inch the cover off, unless you had stainless steel fingernails and hands with gorilla strength. Maybe one day I'll get motivated to muscle that spring loose, but not today.

Phil

You boys are makin' ME want a Predicta...I've seen a few RATTY examples down here, but nothing that wanted me to take it home...A couple of the ones I've seen down here have been very badly painted w/Tiddy Nipple Pink, or Sea Foam/Insane Asylum shade green...And/or look like the plastic CRT covers have been thoughtfully gone over w/40-grit sandpaper...And, of course, the Philistines want 3 fortunes for 'em in that shape, too...

Predictas are the cheerleader girlfriend of TVs -- cute, but high maintenance. If you get one, at least be sure it has a good CRT and flyback.

Phil