K7500 in Golden Tee. Can't fill the screen vertically

blkdog7

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K7500 in Golden Tee. Can't fill the screen vertically

I can't seem to get my Golden Tee 2005's picture to fill the screen vertically.

I have the vertical width knob on the remote board cranked but still have a 1" black gap on top and bottom.

The only knob I didn't touch on the chassis is the vertical hold. Do you think that might stretch it out a bit? I can't get to it very easily, it's in a tight spot.

Or, is this a cap kit?
 
many factors dictate cap operation. particularly heat, the quality of the caps (are they some of the millions of defective ones?) etc.

ok, there's not really an etc. :) really though, ask Ken, Chad, mod, anyone will tell you that there have been times where they put new caps in that were no good.

Chad told me on the phone that he doesn't buy cap kits, that he buys NEW caps in bulk to avoid such a problem with the caps with the shitty electrolyte.

if it means anything, I had a cap kit I put in a K7500 where one of the caps blew instantly.

caps do weird shit. I had jailbars and NO brightness/contrast adjustment on that K7500. capped it, and it worked mint.
 
It seems odd to me that caps are bad already. It's a 2005!

That doesn't mean a thing. Wells-Gardner used bottom-of-the-barrel el cheapo capacitors on the monitor to begin with.

You probably do have some marginal or bad capacitors in that monitor. That vertical size/height control on the remote board should certainly be able to stretch the picture above the top and bottom of the picture tube.

Recap it.

And yes I have seen brand new capacitors bad right out of the package. That's why I always test a new one before putting it in.
 
really though, ask Ken, Chad, mod, anyone will tell you that there have been times where they put new caps in that were no good.

couldn't resist. lol

for fun, I was fixing a pinball machine tonight that would keep losing GIs, and my theory of cold solder rang super true. never seen a whole joint (not the pad) lift before.

and my next piece of somewhat useful knowledge... check for cold solder or bridged traces and the like. I get mixed up lately cause I post in so many threads, but recently in like a Sanyo EZ one I made mention that during one of my capkits on a K7500 that I was in a rush and given the poor lighting conditions I bridged a nearby cap with one of the transistor legs (the one that controls horizontal width... isn't that a horizontal deflection transistor?) and that affected the horizontal size.

so check the vertical I guess. is it really that logical on those that there's a vertical, a HOT, and a horizontal deflection transistor? there's 3 in a row on the big heatsink in the middle.
 
likely a bad 30v supply voltage.. could be a opening resistor near the flyback area where the 30v pumpes out of. maybe a bad tda1771.. i think there is a 1500uf cap that plays a role in height if i recall.
 
likely a bad 30v supply voltage.. could be a opening resistor near the flyback area where the 30v pumpes out of. maybe a bad tda1771.. i think there is a 1500uf cap that plays a role in height if i recall.

Ok, thanks.

I'm gonna cap the monitor and look for open resistors by the flyback. I also ordered the vertical IC TDA1771 in case too.
 
I am bumping an old thread as I am having the same problem. The monitor had about two inches of black bars across the top and bottom, so I did a cap kit but that had no impact. The remote board makes adjustment to the vertical size when adjusted, but not enough of an adjustment. Does anyone have any recommendations and what section makes up the vertical caps?

When I looked at replacing TDA1771, there is some hardened white residue between the component and the board around the screw hole side of the component. What is this white residue and is it necessary as part of the replacement?
 
I am bumping an old thread as I am having the same problem. The monitor had about two inches of black bars across the top and bottom, so I did a cap kit but that had no impact. The remote board makes adjustment to the vertical size when adjusted, but not enough of an adjustment. Does anyone have any recommendations and what section makes up the vertical caps?

When I looked at replacing TDA1771, there is some hardened white residue between the component and the board around the screw hole side of the component. What is this white residue and is it necessary as part of the replacement?

that is heat sink compound. Some people put new stuff on, and others just reuse it. If there is a mica insulator there also, then you must use one when installing the new part....
 
I am bumping an old thread as I am having the same problem. The monitor had about two inches of black bars across the top and bottom, so I did a cap kit but that had no impact. The remote board makes adjustment to the vertical size when adjusted, but not enough of an adjustment. Does anyone have any recommendations and what section makes up the vertical caps?

When I looked at replacing TDA1771, there is some hardened white residue between the component and the board around the screw hole side of the component. What is this white residue and is it necessary as part of the replacement?

Let me know if you fix yours. I still haven't gotten around to mine.
 
So, I capped my monitor and replaced TDA1771 and I still have the issue where I can't fill my screen 100% vertically. Everything else is fine.

I checked a bunch of resistors near the flyback and they all appear to be ok. I did test them in circuit. Was basically looking for zero readings.

Any ideas? Anything specific that I should be doing or looking at? Resistor numbers?

I also swapped pots to make sure my height pot wasn't bad. And, same thing. Is it possible to replace the pot with a higher value? Stupid idea?
 
wells uses around 25vdc to power the verticle section.....there is a test point to check it.TP205 should measure around 25vdc and there are a couple of resistors that I would check to see if they have gone up in value, remember to lift one end to make your reading. R 303 and R 402 are 1.2 ohm resistors and must not be allowed to raise above 1.5 ohms without causing problems. I would also test the resistors around Q602...good luck.
 
In the K7000 sticky you'll find a link to my repair logs on these chassis types, including a fix for not being able to increase the vertical size...
 
wells uses around 25vdc to power the verticle section.....there is a test point to check it.TP205 should measure around 25vdc and there are a couple of resistors that I would check to see if they have gone up in value, remember to lift one end to make your reading. R 303 and R 402 are 1.2 ohm resistors and must not be allowed to raise above 1.5 ohms without causing problems. I would also test the resistors around Q602...good luck.

Tested R303 and it tested at 4ohms. I replaced it. No change. Couldn't find R402 at first glance. Or Q602. I'll pull it out again and check it this weekend.
 
Are you using a 27" chassis on a 25" tube, or vice versa? If it has the pincushion board, try taking it off...
 
Are you using a 27" chassis on a 25" tube, or vice versa? If it has the pincushion board, try taking it off...

I have a 27" tube and as far as I know a 27" chassis. I don't have the pincushion board.

Monitor appears to be completely original and unmolested. But who knows.
 
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If you don't have the pincushion board, you might have a 25" chassis. What's the label say? I've seen a 27" chassis look good on a 25" tube without the pincushion board, so that might be the problem.

Assuming you have a 27" tube. Most GT's had 25" monitors...
 
If you don't have the pincushion board, you might have a 25" chassis. What's the label say? I've seen a 27" chassis look good on a 25" tube without the pincushion board, so that might be the problem.

Assuming you have a 27" tube. Most GT's had 25" monitors...

I thought the pincushion board was just an option for the 27"? They didn't all come with it?

The only difference between the two is the value of one resistor, right?

I am pretty certain this is a 27" model. I'll measure and check the label on the chassis tonight.

I thought most original dedicated GTs had 27"!?
 
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