need advise on adjusting my WG (k7000)

[draginit]

ok, ive identified my monitor with the P538 board to be a (K7000) is this correct?

-at the top of the monitor the image, in a row of about 1½" is being pulled to the left(see pic) before i go turning knobs and what not i was hoping someone might be able to identify the problem and direct me with an easy and obvious solution. thanks

[qrz]

it could need a slight adjustment to horizontal oscillator....however,
if the monitor has any age to it , i would suspect 1 or more  capacitors to be faulty in and around the h osc .

while ur checking caps , b sure to check the bypass cap on the horiz driver xformer .  .47 - 10uF around 50-200 v
(typical value 1uF @160v)
a bad cap here can lead to premature failure of the h out xistor.

qrz

[Kevin Mullins]

Try adjusting the vertical size down a bit.

Is the picture perfectly centered on the tube?
Equally spaced all the way around?

[draginit]

thanks! i am getting out of work early today and will get a chance to try these suggestions today . i will post my results.

[SavannahLion]

Myspace pictures are blocked here at work. Can you upload them to the site itself? I think it'll  be better in the long run should you decide to close your Myspace.

ok, ive identified my monitor with the P538 board to be a (K7000) is this correct?

I have two non-working  P538's mated to different tubes and identifying these monitors was a bit of a bear. They're K7191's. Apparenly, everyone refers to K7000 as the series and not actually a monitor. Additionally there are at least three different versions, a P447 (19"), P538 (25") and a mystery Zenith board. Most readily available information relates to the P447. Menace wrote an excellent posting where he mentions the K7191's. I mention this because the manual might have interesting information pertaining to your question. Even if it doesn't it's always good to have the service manual.

[draginit]

ok, ive uploaded the pics into the site  .. started with the verticals and made sure the picture was centered. went to this next screen and found the top line in the grid does not move: --edit you tube continually fails to upload my video, ive given up and used this...
Click here to watch screen-adjust

with the top line staying put, it doesnt matter where or what size the picture is on the tube as thats section is always stationary.
my workaround for now was getting the rest as close to center as possible. but it leaves just the smallest kink in the picture at the top. im gonna want to try and fix this but here are my results:

[Kevin Mullins]

Just from looking at your video clip...... I still say the picture is stretched out too far. You should be able to see that entire grid on screen without having to shift it from side to side or top to bottom. All four corners of that grid should be visible at the same time.

Adjust the vertical height and horizontal width to bring it in.
Then center it.

The picture is otherwise really good, which is why I lean towards an adjustment versus a chassis problem per say. The problem at the top appears to be more of a foldover type issue due to it being stretched.

IMO of course.

[draginit]

correct me if im wrong but isnt this(pic) the horizontal width coil? its directly behind the flyback.
if so, ive searched for the plastic tool part # on here but couldnt find it. i think ken posted it once before.
i have the v-pos, v-hold, v-size, and h-pos, all conveniently located on a remote board but the h-size is nowhere to be found, so its gotta be this coil then yea??


--bottom picture-- here is the kink i was talking about. kevin- you are suggesting that when i am able to bring the horizontal image back in it will straighten this out? its at about as close to straight ias it will go atm.

[Kevin Mullins]

Yeah, that looks like it. You can usually find a set of TV tuning tools at Radio Shack for like $5.00 - $6.00 that should do the trick.
Just DO NOT use a metal allen wrench or screwdriver to try and tune that with...... you WILL break the ferrite core.

EDIT: Radio Shack Link

[draginit]

ok, i was able to take that part# to radio shack and pick up the kit. and glad i  finally have a set!   so now i turned the coil all the way down and saw no change. as well as all the way up. so that means its toast right?
-i havnt replaced one before and my soldering skills are ok, is this something i should/could take on?   or is there something else i should check around the coil?

[Kevin Mullins]

If it isn't physically broken, then it should be fine.
You may end up having to do a capacitor kit on that monitor.

A good read about width stuff - http://arcadecontrols.com/BBBB/width.html

My main reason for having you try to adjust it out first is simply to get it to a good starting point before truely troublshooting the main chassis as being at fault.
i.e. - The test grid didn't even fit on screen. So trying to adjust that out might have solved your problem. A stretched picture may shows signs of rollover, which is what yours looked like to me anyways. But.... a bad capacitor can cause similar problems.

[draginit]

that is an awsome write up, thanks for showing me that. after reading it, i pm'd menace and requested a copy of his schematic for the p538 boards. my board is really dirty and i cant find C38(the common one) while its all connected. i'll probably have to remove the board but i'll wait to see if i get the schematic to make things a little easier. it probably wouldnt hurt to clean this thing up a bit as well anyways..

[Kevin Mullins]

Scematic:
http://www.wellsgardner.com/pdf/Schematics/K7000_25_27_inch.pdf

Parts List:
http://www.wellsgardner.com/bom/P538.pdf

[draginit]

thanks for the schematic!  well i ordered a cap kit, it will be my first time installing one. i'll post my results! or if i have any question of course.....

[Zebidee]

You can find heaps of useful info on the k7000 from Bob Roberts.  Look here:

http://www.therealbobroberts.net

He also sells capkits for 1/2 the price of WG 
and complete repair kits for only $26 (includes capkit, flyback, HOT, fuse)

http://www.therealbobroberts.net/parts.html about 2/3 the way down the page.

I also have a P538 style W7000, and have just ordered the repair kit as my chassis has a number of badly leaking capacitors and possibly other probs too.  At the very least, it'll be handy to have any extra parts available (esp. the flyback & HOT at that price).