Can someone post pictures of u5000 with upgrades for easy identification.

Jimjaycee

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Can someone post pictures of u5000 with upgrades for easy identification.

I recently have moved to newer monitors and I'm looking for information.
 
Except for a heat sink added on one transistor, pics of an upgraded U5000 won't look any different than one that hasn't been upgraded. What you need to do is check the values and part numbers of those parts to see if they match the upgrade list or not. If so, the upgrade has already been done.

Ken's sticky for repair guides has the link where you can get the upgrade documents...
 
Took a meter to the hot, it is fully shorted. With that, I'm sure the fly is gone.
Add it to the issues...

Not necessarily. I see HOT's blow all the time on these and the flyback is still fine.

And you have to make sure you only test the HOT with the black lead on the center leg and the red lead on each of the outer legs. Between the two outer legs will test as shorted normally...
 
I tested it again, as you suggested, and it is shorted.
This monitor was in a 99 golden tee.
This main connector was plugged in for standard res.
The 2 point outside plug for the medium res. was connected to
the resistor. I don't know if this added to the breakdown.
 
What is the problem? I've worked on many of these:

http://forums.arcade-museum.com/showthread.php?p=1710227#post1710227

Randy Fromm has a flowchart for the K7400/K7500 that is partially useful, since it has some of the same circuitry, and he made one for the U2000 which is also partially useful - but there is not one specifically for the U5000. I may try to make one at some point.
 
At this point the monitor appears dead, no ticking. I remember hearing about a
light bulb trick on this kind of monitor to check switching power supply on board.
I do not know all the details on that procedure.
I know the hot is shorted out. The fuse is still good.
My original plan of action is to replace hot, fly and cap it.
At this point I still need to order hot and fly. I have the cap kit.
Some of the upgrades have been done.
 
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At this point the monitor appears dead, no ticking. I remember hearing about a
light bulb trick on this kind of monitor to check switching power supply on board.
I do not know all the details on that procedure

Get a small table lamp, turn it on, then unplug it. Run a jumper from chassis ground to one prong of the plug. Then run another jumper from TP202 to the other prong on the plug. Turn your chassis on. If the lamp lights, then the power supply will be good. You should get a B+ reading of 117vdc at TP202. Make sure the yoke is connected when you do so, and you may want to isolate the anode if you don't have it in the tube.

If the light doesn't come one (and you have the right yoke plugged in)and the B+ is too low or too high, then you have a problem in the PS section also...
 
This chassis does not pass the test for TP202. I found the 10k 7watt resistor open so far.
I did replace it with the 10 watt resistor recommended on the upgrade sheets. I also replaced the 470ohm one as well. What else should I be looking for to get the voltage going into the rest of the chassis?
I did do a complete Bob Roberts cap kit too.
Another update TP 106 is at 177 volts AC, when tested off the chassis. I can hear a real light tick. Normal is 155 when set in Standard Res. Obviously now in HV shutdown...
Any ideas?
 
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Is all you've done is replace the two resistors? You mention you have to order a cap kit and the HOT, but have you replaced these items yet? Do the cap kit as this can cover alot of problems you can find with a chassis of this age and see if you are still having a problem with the power supply area.
 
I went back and edited my last post...the hot and fly have been replaced as well as doing a full cap kit.
 
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It is presently up on the bench, with the chassis out. I've also discovered R112 is fully shorted. I'm trying to find a replacement at the moment. It is a 560 ohm 1/4w. I usually go up a to the next wattage if I replace something.
 
did you lift one side of the resistor to measure that....there is a inductor across that resistor that can make it look shorted in circuit? I have never seen that one before....
 
so....no 12vdc to drive the horizontal circuit.....you still have high B+? This is typical and you need to find why the 12vdc is missing. The area I would be checking is around Q708 and the resistors in the surrounding area....like R720, R760 and R765.....
 
703 & 708 were replaced I will be checking the resistors as you stated tomorrow. Enjoying a few tasty beverages now...
Thanks for your input. This is going to be in a GT Fore when is done.
 
Resistor r760 is reading 500ohms instead of 100ohms as stated in the manual. I also heard a bad z-diode in that section can cause the fault on pin 10. Hopefully I will figure out more on this chassis, and a solution.
 
personnally, I have never found a bad zener diode in that circuit, but I'm not saying it can't happen. Replace the bad resistor and recheck for 12vdc to the IC.
 
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