Please ID and concerns

[modessitt]

There is a big white resistor on the outside of the wall on the left. Measure the side closest to you. That is your B+. Set your meter to DC 200. Red lead on the resistor and black lead on the frame.

And make sure the black wire is connected between the tube and the neckboard anytime this is powered up.

And I often see these "dead" and come back to life simply by fixing a cold solder joint on one of the big power resistors around the horizontal width coil...

 

[chris25810]

Desolder one leg of the D10 diode and try the monitor again, the regulators are notoriously crap in these chassis. If the monitor fires, there's your problem

 

[jay]

Will do. I'm at work so I'll report back later today.

For my second cap kit, that part went very fast this time. The old flyback kicked my butt. I had a very hard time getting it off of the board.

I did try just doing the cap kit and leaving the other stuff. When it still didn't work, thats when the fun began...

Thanks again for the suggestions and help.

 

[chris25810]

The failed caps most likely caused the regulator to short out. These damn 7000's can really be a moneypit. Make sure you take a real good look at the solder pads around the R89 and R101 resistors, this is where the boards cook themselves to death. Wiggle em around and watch the bottom side for any movement.

 

[jay]

Just checked the B+ (big white resistor, bottom left on the board above the PFC...right)

I'm getting 171Vdc. Seems high to me. Where is the adjustment for the B+??

 

[chris25810]

There really is no adjustment for the B+ desolder the D10 diode

 

[jay]

Pulled 1 leg of the D10.....nothing. Reflowed suspect solder joints.....nothing.

 

[jay]

So I guess it's not the reg at this point???

 

[KevinMullins]

Measure the input voltage on pin 1 and 2 of the voltage regulator.
(pin 3 is ground, pin 4 is output)

 

[jay]

Just a question:

I have no way of testing the reg with everything connected. This cab is a nightmare. I can connect power and test it outside of the cab. With this in mind, what happens if this thing decides to come to life with the anode cup detached?!?!

 

[modessitt]

Just a question:

I have no way of testing the reg with everything connected. This cab is a nightmare. I can connect power and test it outside of the cab. With this in mind, what happens if this thing decides to come to life with the anode cup detached?!?!

The best thing to do would be to pull the entire monitor from the cab, then set it on the floor or on a stand behind the cab. Connect it up and have easier access to do your voltage checks.

If you really know what you're doing, you can do testing of a chassis without the anode cup connected, but you have to keep it away from you and anything metal (including the chassis). Considering your monitor isn't working now, you probably won't have any HV anyway, but you always be safe.

And don't test it without the dag wire connected....

 

[jay]

If you really know what you're doing

I think we all know the answer...:}

I really really don't want to pull the tube. It's facing down and will have to come out that way. I'm sure getting it out is not that bad. Putting it back in would seem to be a giant pain.

As my last resort, I'm going to order a reg from BR and hope that works. If not, I'm calling it quits.

I'll let someone who knows what the hell their doing play with it. I know a bench tech at work that can perform miracles. Didn't want to bother him with it. If not, then I guess I'll pay for someone to repair it.

I'm afraid I'm causing more damage with my shit ass soldering skills.

 

[modessitt]

I've found that techs with excellent PC board repair skills can have no clue when it comes to fixing monitors. Monitors tend to be different animals, especially monitors that were made 20+ years ago...

 

[jay]

This guy (the bench tech) has repaired many tv's. I've also watched him reverse engineer our RF mini-bridgers, line extenders, fiber nodes, and make his own schematics when none were available.

He's our "god" and has saved the company thousands and thousands of dollars. I would trust him with anything electronic no matter the age or cost.

Again, I am hesitant to ask him for "one more thing" to do. He's a busy guy. I'll probe him a little and see

 

[jay]

This seems interesting...

http://www.therealbobroberts.net/dead.html

Besides the reg, I guess I'll be ordering more parts....

By the time this is over, I think I could have sent it to someone to be repaired for cheaper.

I'm thinking it's worth my time and money in the long run. At least I'm learning.