U5000 is the big wite brightener block on the fly really needed.

Buffett

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U5000 is the big wite brightener block on the fly really needed.

on a U5000 is the big wite brightener block really needed for the fly to function properly.

i am fixing the chassis and don't want to order a new fly if i dont have to. this one seems to be fine no cracks or goo leaking out of it.

just the ground to the brightener block broke off where it comes out of the epoxy and unless i dig out epoxy to get enough wire exposed i will just take off the brightener.

it came out of a cruising exotica sit down if that matters. i would not think it would for this game.

so can i just remove the block and go without it?

it will get a all new cap job and other things replaced so plus the traces on the neck are lifted so i will repair that as well.

the game is not mine and i never saw the monitor wile it was in the game running. so more may be wrong with the monitor i don't know. but I will test a lot of other things before i power it back up.

Peace
Buffett
 
not working yet please help

OK so i get everything all fixed up.
i have omitted the brightener. and kept the old fly back on it as i have no replacement at the moment i may have to order one i am not sure yet.


the chassis powers up half way and has a soft hissing like sound coming from it. i cant seem to isolate where it is coming from yet.

i have no high voltage as no static is present on the screen.

the fuses does not blow.

i have not checked the B+ on it as i do not know where to do it yet on this chassis. i don't fix enough U5000's at the moment to know. but i do need to know if some one can please tell me where to check it. and let me what it should be.


other wise all seems to be good with it. the H.O.T and VR test good as do the diodes around the chassis in the power circuit ect...

any help to what i need to test next would be great thanks.

Peace
Buffett
 
The brightener is not needed - although if you put it in a gun game, it may need to be back.

A hissing? not a click?

B+ is tested at TP202. It should be about +117vdc.

Perhaps the startup circuit isn't kicking on? Check (in this order) R760, Q708, R765, ZD702, ZD705, and C713. A lot of times I find R760 open.

You may also turn off the lights and see if the "hissing" is a sparking anywhere? What did you do about the wire you cut to remove the brightener? I usually wrap it in electrical tape pretty good, and it seems to work fine. You may be hearing some HV leakage...
 
OK cool the brightener is not needed i did not think it was.

the monitor is out of a cruising exotica. and that will be its home when its fixed. no gun game for it.

cool thanks for the B+ and what it should measure. i will check it out in a few.

no it is a hissing noise almost like running water. no click is present. i have heard the click on other chassis like sharps and others. it is definitely a hissing.

the hissing is not very loud it is real soft and does not change pitch at all.

i did not cut it out i removed the wire from the anode clip in the boot and put it back together. it was not soldered originally so i did not resolder it upon reinstalling it. but i may try and solder it to the clip as it will take a little modding to the boot to get that done. so it is possible it is not making a good connection as it is a pressure fit in the boot.

i will test all those parts when i remove the chassis in a few.

but i will turn off the lights and see if i have some arcing any where and check the B+.

ill test and get back in a few thanks for the help.

Peace
Buffett
 
OK quick update.

it fires up for a split second after it sits a couple minutes.

then goes into HV shutdown. B+ measures 155v.

still has the low hissing. no neck glow.

but good news there is no sparking any where.

so now i will test all the parts you said to measure.

any other ideas of things to check wile i have it out let me know.

Peace
Buffett
 
Have you isolated the power supply section with a lightbulb test to make sure it's working properly?

Going to bed now...
 
BTW - I was incorrect. B+ should be +130.

If it works with the PS isolated (light bulb lights up), then you have an issue in the horizontal deflection circuit...
 
no i have not done the bulb trick. i have read about it but something on how to do i am not understanding. i don't know why i am not understanding about it.
i understand what it does but cant figure out how to do it for some reason.

here is the test results i have found.

R760 is 474.6 ohm out of circuit. the manual says it should be 100 ohm.
wich one is correct i have found the manuals to be wrong some times.

R765 shows open and will need to be replaced.

is there any reason they would fail? if so what else should i look for.

everything else looked and tested good that you said to check.

Peace
Buffett
 
BTW - I was incorrect. B+ should be +130.

If it works with the PS isolated (light bulb lights up), then you have an issue in the horizontal deflection circuit...

out of curiosity, where'd you get that number from? I'm quite certain even Chad says it's supposed to be 117V. I know the K7400/K7500 are supposed to be, I'm sure the U5000 is the same.

I know from experience that the K7400/K7500 will trigger the shutdown (high B+, not sure if it's ever up to 150V however, given that the monitors still worked intermittently) when they're ready for caps. I suppose install the cap kit and check the results afterward?

what's that one upgrade kit, the one that has something to do with the chassis eating HOTs, would that have anything to do with this?
 
There is a slew of DC voltage test points listed in the manual.
Here's just the usual "TP" ones, but there are many for different components listed as well.
 

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OK, 117vdc was correct. I went to check something on a flowchart and it tried to tell me it should be 130vac.

R765 is probably the problem. I don't know of any reason it fails other than the stress of starting up over and over. I've never found another issue, and replacing usually fixes it...
 
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BTW - the easiest way to do the "lightbulb" check is to get a small desklamp. Using two alligator jumpers, connect one to one side of the lamp plug and the other end to TP202. Then connect the other jumper to the other side f the lamp plug and connect it to the monitor frame. Turn on the lamp, then turn on the monitor and see if the lamp lights. You'll probably get a good B+ reading at this time, even if the monitor still doesn't work. This just shows that the PS section is good...
 
cool thank you for explaining the bulb trick i will try that and see what happens.

cool ill order the resisters and see it that gets the job done. maybe ratshak has them ill have to see.

thanks for the help i am new to theses chassis types. they are essentially the same just more modern on how they get it done.

so is the manual correct in that R760 should be 100ohm?
and my reading is bad at 474.6.

i don't see how it could be so far out of tolerance and still give a reading like that. i would think it would have gone open.

Peace
Buffett
 
i cannot rember except i think it had a double orange together and i don't know the third band.

i cannot find it rite now. i moved some stuff on the table before i went to bed and it got swept off the table. i have not found it yet.

if not i will get both and try them.

worst that will happen i am guessing is ill have a warped pic with one and not the other. or the wrong one will smoke and the other will not.

but i will try and find it later when i get home.

Peace
Buffett
 
I'm sure it is a typo but B+ is a DC voltage, not AC. The schematic says that resistor 760 is a 470 ohm 1/2 watt resistor. R 765 is part of the circuit that sends the 12 volts for the horizontal circuit to function and is most likely why you are unable to get a picture. Once you can read 12vdc on pin 10 on IC U701, you should have a picture, as long as there aren't any other issues. Good luck.....
 
we have a working monitor!!!!!!!!!!

OK update the chassis is up and running.

R765 was a 33k ohm resister and it was open. i replaced it and the chassis comes to life.

R760 is 474.6 ohm tested out of circuit i left it in so i guess the schematics were correct and the parts list is not.

thanks cbuschief for pointing that out.

also the B+ was low around 114.2vdc so i adjusted it up to 117vdc and so far it is holding steady.
i will let it run for a while and adjust it again after it warms up if needed.

now i don't have a med res PCB here to test it.
is there any thing that would not let it work when i hook it back up to the cruising exotica.

so is there any thing i should check or do before i travel 40 minutes and reinstall it into the game and have it not display a pic.

thanks to all for the help in fixing my first U5000.

Peace
Buffett
 
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There are very few issues that would occur as med-res but not as standard-res, and they would be sync related - not start-up related.

You can disconnect the video input, then set the jumper for med-res and make sure it starts up and you can turn the brightness up and get raster. That will at least tell you it works in med-res mode.

And you'll have to adjust hold and position once you change to a med-res signal...
 
FWIW, there is a cap (22mf I think) next to the MOSFET part in the power supply that when bad the power supply will run high and make that "sizzle" noise that you had at one time.
 
cool i will at least see if i get raster before i take it back.

But new problem.

letting it run for an hour or so after getting it all fixed up for testing purposes.
i come back to the bench and it is ticking like a clock.

so i guess the H.O.T went out on it.

so now i will need to get it back out and see wats bad now.
good thing it did this before i took it back and reinstalled it in the game.

any thing else but the H.O.T that i should look for.

you think with all new caps it stressed the fly and i should get a new one for it.
i haven't looked at it yet i went to bed after turning it off for the nite.

i guess the stress of new caps pushed it over the edge and it gave out.

so almost there. i know that the U5000 is a different animal but will a K7000 hot work as a replacement? i have them readily available.

so is it not rated strong enough or it to weak to work. or is it just pined out different and its not worth modding it to work. and i need to get the correct part. i hate having to ship just one part that costs as much or less than shipping does. we have no place like a fryes around here.:(

Peace
Buffett
 
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