19K7000 Focus Issue

Peale

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Received a 19K7000 for repair. Wasn't DOA - but was close. Heater on, no picture at all. Has been capped in the last few years, so I have not yet touched them. Has a hack repair job in the power supply (bad bridges, burns, lifted traces, tarnished pads). Corrected all that I could find.

Upon power up, we have picture, but out of focus. Noted that you can adjust the focus, but it only changes things, it never actually gets anywhere close to being able to focus. It's really, REALLY far off.

White knobbed flyback (with the characteristic cracks around the focus knob), so I thought perhaps the flyback was at fault. Changed it out with no change.

B+ is a bit high (129VDC), but not overly so.

Thoughts?
 
what about in the neck socket.
is the focus clip bent up in there, can you see it at all without tearing it up to take it apart.

i would swap neck boards to see if there is a change.

and if there is swap the socket next.

i have one kinda like that but it is my chassis so i never got back to it.
it will not focus at all, there is an effect when the focus knob is turned but
it will not completely focus. you max it out and that is the best it will get.

and my B+ is off on it as well. i just ant remember if it is high or low.

Peace
Buffett
 
if its a 19" it probhably has some flavor of sXXX123 regulator. In that case, b+ should be 123v. for reference if it was a 25" chassis they usually came with a sXXX130 regulator, or course b+ on those should be around 130.

Id make sure someone didnt put in the wrong vreg. after that checkover neckboard(krappy socket maybe??) and check the tube with a revuve for giggles.
 
Yes, you can see the focus pin just fine. It would appear that it makes good contact with the pin on the tube, but what I would consider good contact, and someone else....well, that's two different things.

The connection isn't broken between the wire from the fly to the socket, it Ohms out fine.

I'm reluctant to swap neckboards, if only because I've only got just the one other one, on a tested, working unit, fully rebuilt, ready to sell. I'd swap sockets...except I don't have any, as far as I know.

To rule things out, I'll probably swap the neckboard anyway, and then at least I'll know if the issue is there, or not.
 
Check the focus wire connection inside the tube socket on the neckboard.

Double check the tube's condition on a rejuvenator.
 
what about in the neck socket.
is the focus clip bent up in there, can you see it at all without tearing it up to take it apart.

i would swap neck boards to see if there is a change.

and if there is swap the socket next.

i have one kinda like that but it is my chassis so i never got back to it.
it will not focus at all, there is an effect when the focus knob is turned but
it will not completely focus. you max it out and that is the best it will get.

and my B+ is off on it as well. i just ant remember if it is high or low.

Peace
Buffett

Probably low not enough juice=not enough focus powaoh!!! Seen that on k7s with bad caps vreg issues etc had to have focus maxxed out to even be close
 
if its a 19" it probhably has some flavor of sXXX123 regulator. In that case, b+ should be 123v. for reference if it was a 25" chassis they usually came with a sXXX130 regulator, or course b+ on those should be around 130.

Id make sure someone didnt put in the wrong vreg. after that checkover neckboard(krappy socket maybe??) and check the tube with a revuve for giggles.

Tube's fine, it's my reference tube. Unless the chassis killed it somehow (and I should probably swap it back out with my known good chassis to be sure...).

Regulator is the correct one. First thing that I checked.
 
This is one of those times that I wish I had a proper cap testing meter. The caps are newer - but, I'm betting one of them (or more) is bad.
 
Check the focus wire connection inside the tube socket on the neckboard.

Double check the tube's condition on a rejuvenator.

Tube is fine (reference tube on which I use for testing chassis'). But will test to make sure the chassis didn't ruin the tube. Connection is fine, was good before swapping flyback, and the problem persists.
 
ok.. wanted to make sure somebody didnt stuff a 25" chassis on there lol. Seen stupid op hack stuff like that before.

447= 19 incher (usually) so youre good there. hmm..

at this point id shotgun all the big caps around the flyback/fuse area (and verify correct values in the process) and see what i got. Suspect you might have the wrong vreg in there as well but changing that would likely make this issue worse not better.
 
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The very first thing I did was verify that the vreg is the correct one.

Was hoping to avoid capping this completely, but...oh, well.
 
Turned out to be the neckboard. Swapped it with one from another chassis, and the focus cleared right up. Guessing the socket (though it Ohms out fine) but don't have any to swap out the socket to test right now.
 
pay the shipping and i will send you a socket from a tv you can swap in.

i would like to know if that fixes it.

Peace
Buffett
 
pay the shipping and i will send you a socket from a tv you can swap in.

i would like to know if that fixes it.

Peace
Buffett

Pretty sure that I have at least one - but, I need to be able to get to my box of TV chassis.

I'm in the process of a divorce, and everything is this way and that.
 
Pretty sure that I have at least one - but, I need to be able to get to my box of TV chassis.

I'm in the process of a divorce, and everything is this way and that.


cool hope you have one.

good luck in the divorce give her nothing.

Peace
Buffett
 
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