K7500 re-capped now width won't fill screen

[mecha]

I posted about this very monitor a couple weeks ago about it shutting off randomly, which I found was being caused by the HV Shutdown. I installed caps in it tonight and when I powered it on to try it out, I found the Width pot has like zero functionality in stretching the horizontal size to where it should be.

I don't know anything about the B+, I've never measured it before, and I've never adjusted it, but considering my shutdown problems I had before and how apparently the K7500 is picky about B+, would that have anything to do with the width, or is this a matter where I just have to adjust the width coil?

and is it customary for a monitor to look perfectly normal, but have caps fucked up to the point that after installing new ones you have to go as far as to adjust the width coil, or did I botch something here?

am I correct in understanding that any caps that are around the width coil are the ones that have to do with horizontal operation?

I just adjust colors or if a monitor's bad enough I re-cap it, I haven't gone into all these like sections or the other items outlined above.

thanks.

 

[modessitt]

You know that transistor in the back right corner mounted to the frame with a connector to it? You have the connector on backwards...

 

[mecha]

are you serious? I didn't mess with that though. this game worked fine for like 2 years.

I don't think this one has that transistor like that, I've seen a few variations on the K7500 where the big heatsink will have anywhere from 1 to 3 transistors mounted to it. this one has the 3rd one mounted to the heatsink, I've seen them before where it's got wires running to a little 3 pin red connector that links to a transistor, if that's the one you're talking about.

EDIT: yes, that is the one you're talking about. this one's got it hardwired to the chassis.

so now what?

 

[modessitt]

are you serious? I didn't mess with that though. this game worked fine for like 2 years.

I don't think this one has that transistor like that, I've seen a few variations on the K7500 where the big heatsink will have anywhere from 1 to 3 transistors mounted to it. this one has the 3rd one mounted to the heatsink, I've seen them before where it's got wires running to a little 3 pin red connector that links to a transistor, if that's the one you're talking about.

Yeah, that's the one I'm talking about. If it was there, then you unplugged it to remove the chassis and do the cap kit. If it's on backwards (or not connected), then the width is too narrow and won't adjust with the pot. Putting it on properly will then allow you to adjust it fine.

Check and make sure you don't have one...

 

[modessitt]

EDIT: yes, that is the one you're talking about. this one's got it hardwired to the chassis.

so now what?

Check it for good functionality, and no cold solder. if you installed any caps near it, check them for proper polarity or solder bridges or damage nearby...

 

[mecha]

I had a rough time with solder pads lifting on this chassis. I'll have to take another look at it tomorrow. there's a possibility I fucked something up doing this job at the end of the night and under the gun, because the width pot doesn't change anything, but the height one is fine.

I only had it on but about 2 mins, I didn't smell anything get toasty or notice any waves or other abnormalities in the picture, and I know my cap polarities were good. (it's why it takes me 3 hours to do vs. your 30 minutes you speak of )

I should've touched up the solder joints, but like I said, this one was a total shitpiece, had about 5 pads lift on it, I wound up crossing the legs in like an X pattern to get them to hold tighter and then I snipped them off, OR I went to the next point in the circuit OR scraped some trace and soldered direct to that.

I'll give it another look when I'm not fried tomorrow.

 

[mecha]

problem solved. was a gd bridged cap to one of the legs on the transistor mod spoke of. monitor's been fine all day.

 

[cadillacman]

glad to hear you fixed it. Now lets hope the thing hangs in there for awhile...

 

[PrairieDillo]

awesome fixing something right and getting the good help.

listen for the sound of applause......

I've a bunch of monitors in my garage/games to work on now also. I'm seriously going to need help advise also.

 

[mecha]

glad to hear you fixed it. Now lets hope the thing hangs in there for awhile...

yeah, this is the one in our Carnevil. I think you can understand the importance of getting that working lol.

awesome fixing something right and getting the good help.

listen for the sound of applause......

I've a bunch of monitors in my garage/games to work on now also. I'm seriously going to need help advise also.

yeah, it sucks that it took mod for me to realize I had a bridge though. this chassis as I mentioned was difficult to work on cause of the solder pads lifting. wasn't as bad as this one U5000 I did though, that one was already hacked to shit, and most of the caps that were in it were of ratings that were WAY off.

I'm just glad I didn't cook anything.

I think I learned some things about that 3rd transistor (the one mod talked about) and why some of these junk 7500s I have either have empty spots or they have jumper wires going to the red connector you plug into the transistor OR the 7500s I have that actually work that have them soldered in.

anyone know what that does? does it have to do with the horizontal width or was that just an anomaly of me shorting a cap to one of the legs? lol

 

[mecha]

not the HV shutdown pot itself... what else should I look for to be shorted or causing this thing to go out of range?