New flyback transformer won't foucs

dyno

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Got a new flyback transformer for my Hantarex polo from bob roberts and when I turn the focus knob on it nothing happens on the screen, is the flyback defective? The part number on the flyback is a hr7191, is that the right flyback for a 25" hantarex polo? Did I miss something when I installed the flyback?
 
Sounds like a bad connection at the neck socket. The pin on the tube could also be bent or the socket could be bad. You can check the voltage on the focus wire if you think the fly is bad. But you will need a HV probe as the voltage will be around 4000 volts.
 
you didn't reverse the G2 and focus wires did you? have to go by the thickness, not the colors lol

if you did, you'd see like a rainbow line pattern in the middle and it would be buzzing when it's on. (I've done this before... stupid)

oh also, which kind of neck socket do you have? the door kind where you solder to the terminal inside or that other kind that... I never figured out.
 
I don't think I reversed the wires, don't get a rainbow line pattern in the middle. But I will have to double check on that. The monitor has started making a more of a high pitched whining noise than a buzzing. The socket on this neckboard is the other kind, not the door and I couldn't figure it out either so I just cut the old wire and soldered the new one in. I do have another polo chassis that has the door kind, wonder if I should try swapping the neckboards. I did check for continuity from the wire to the neckboard and that is good, maybe the pin on the tube isn't making contact in the socket of the neckboard. I can get the picture to almost focus but seems to be just a bit off.
 
Checked the wiring and I didn't mix up the wires. I noticed when I turn the screen knob on the flyback that the screen will go out of focus and then if I adjust the contrast it will go back in to focus which I don't think is suppose to be happening.Still getting nothing from the focus knob on the flyback when I turn it.
 
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Check your connections on the flyback that go to your focus adjustment control. I had the same problem and found out the wire connector was not completly on the post. There was a rubber boot over the connector and post and I could not tell the wire had slipped off and was only making intermitant connection.
 
It could also be a bad socket. Doesn't happen often, but when it does it can be tricky to diagnose.

The last one that I had with this issue seemed to have good contact, but it wouldn't focus. Replaced the socket, and it was 100% again.
 
I do have a second chassis for parts, maybe I will try putting that neckboard on it

mark the ribbons. easy to reconnect them backwards. (or upside down, rather) also verify you soldered all the flyback pins in, there's a pin on the replacements that's just tucked underneath and a lot of KLOV folk say "oh, you don't need that!" but trust me you do. I verified it on 2 Polos. I wanna say that can cause the weird focus adjustments when you mess with the screen pot.

remember the G2 wire is the thicker of the two. the colors on the replacement Polo flybacks are usually kind of reversed from a stock one. I just can't remember the damn colors off hand, don't have any of my game stuff here.
 
The 2 polo chassis I have are a bit different from each other, the neckboard on one has a blue gain and red gain knobs and the other has green gain and red gain knobs so can they still be swapped? I made sure that the pin tucked underneath was connect and I have connected the thicker wire to the focus pin on the neckboard. This is getting a bit frusturating, I can get the picture to focus so it can be played but it seems just a bit out of focus and if the focus adjustment worked I am sure it would fix the minor tweeking needed.
 
The 2 polo chassis I have are a bit different from each other, the neckboard on one has a blue gain and red gain knobs and the other has green gain and red gain knobs so can they still be swapped? I made sure that the pin tucked underneath was connect and I have connected the thicker wire to the focus pin on the neckboard. This is getting a bit frusturating, I can get the picture to focus so it can be played but it seems just a bit out of focus and if the focus adjustment worked I am sure it would fix the minor tweeking needed.

thicker wire's the G2. you're backwards.

if I'm right off memory, the wire sticking directly out the top is the G2. G2 would normally be red, I think it's white. and the focus wire's a different color. I wish I could remember the friggin order. let me look in my pics.

EDIT: I may be stupid. here, maybe these pictures can help you: http://www.organizedmassconfusion.org/hantarex-polo-maintenance/
 
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I connected the thicker black wire coming out of the top to the focus pin on the socket and the red wire coming out of the bottom to the g2

That's correct. mecha got it backwards. The larger (4000 volts) focus wire goes to the neck socket the smaller (400 volt) G2/Screen wire goes to the neck board.
 
That is what I am thinking I might do and see if that helps.I am hoping it will, sometimes the screen will be in focus then go out of focus a bit and I have to adjust the screen control on the flyback to get it back into focus.
 
Is the tiny pin on the front of the flyback connected to the chassis? That provides the ground for the Screen/ Focus pots.

What was the problem before you changed the flyback? Have you ever seen the monitor work with a good picture. There could be a G2 to Focus grid short in the picture tube.
 
Yes, I made sure that the tiny pin was connected and I just reflowed it tonight. I got the cabinet for free and the monitor wasn't working and the chassis on it looked pretty messed up. I bought a non working chassis from a klov member, when I installed it the flyback blew a hole in it when power was turned on so that is why I replaced the flyback.Not sure what the pciture quality was before hand on the monitor.
 
Any chance you have a high voltage probe? If you knew the range of voltage on the focus wire as you turn the pot it would be a big help. There is always a chance the new fly is bad.



Here are the symptoms of a screen to focus grid short.

"Screen to focus (G2-F). Screen (G2) and focus voltage will be the same and
the controls on the flyback will interact. Result will be a fuzzy white
raster with retrace lines and little or very low contrast picture. Symptoms
will be similar to those of a flyback with breakdown in the focus/screen
divider network. "
 
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