WG 6100 blowing F700 and F600

komodo

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This is driving me crazy. First off, these are the fuses for the X & Y circuits, not the power circuits. They are the 3 amp normal blow fuses on the deflection board. I shall summarize so please read carefully. I have gone completely thru the deflection board and checked all components. Yes, it took a long time. All cold solder joints fixed. LV2000 installed. This was a tested and working deflection board till one day the monitor quit on a Tempest. All the bottle cap transistors are fine. Yes, I do know how to test them.

Every time I try to power up the monitor using a known good Tempest board set, I blow the fuses at these locations. I have tried the monitor and 3 different board sets in 3 different cabinets. I decided to try a different deflection board to see if it might work but the same result. This one does not have the LV mod but that shouldn't matter anyway. AT NO TIME is the HV section connected so we can keep that completely out of the loop here. If I hook up the large connector only all is well. I have good 26V on the LV 2000. When I hook up the power transistors and deflection circuits and yoke and neckboard, KABLOOEY. The fuses blow in about 2 seconds. I am thinking that the yoke may be shorted somehow but would like to know the definitive way to test it. Mind you this monitor has no burn on it and the tube looks like it just came from the factory. However, the yoke mounting looks like it was done by a guy on his first day at work so I don't know if this is a factory install or somebody bought a new tube and mounted the yoke on it a few years back. I know the monitor came from Callan in Houston but have not contacted him as I doubt he will remember the providence of a tube from about 6 - 8 years ago. But I digress...........

I checked the resistance of the 2 different windings on the yoke and they are close to another monitor I have here in the garage.

1. Do we know the "values" the 6100 yoke is supposed to put out?

2. Is there a good way to test the yoke that I don't know about?

3. Can I put a bare yoke on a piece of wood and plug it into the deflection board and power up the circuit without blowing anything? That is, no tube?

4. What order would you plug in the power and deflection transistors to test each circuit?

5. Does the yoke have to be plugged in to test the deflection board or will I cause Magic Smoke to leak out of something if I leave the yoke unplugged?

Some of these questions may seem pretty basic but that is the kind of guy I am. Very basic. Until then, I'm going to try another monitor with the same boardset to see WTF is going on. I'm running out of 3 amp fuses.
 
Pat,

Since you have been through it so much, it is probably something that your just overlooking. You said you tested all the parts, did you validate that they are the right parts? Are all the chassis mount transistors paired up right and connected using the right mounts (2N3716 on pins 1,3,4 and 2N3792 on pins 5,6,7)? I could see someone doing those wrong and me not checking. :) I know some replacement parts might have to be flipped based on the manufacturer since they don't always use the same pin out and have to be flipped. I have seen that a few times on NTE parts in general. If this is a problem would likely be on the heat sink transistors (Q603, Q604, Q703, Q704).

For the yoke, you can just measure the resistance on each coil. Just unplug the yoke and test the two coils with your meter. I posted the following values in another thread.

The last time I tested my 6100 I had the following values (X Yoke: .5 Ohms and Y Yoke: 1.2 Ohms).

I tested another yoke last night when rebuilding the monitor on that space duel and they were basically the same. You can test the deflection board with everything unplugged except the main connector. You will get smoke on the resistor for the degaussing coil, so go ahead and hook that up.

Good luck finding what is causing the problem. It sucks when the fuses are blowing as you cannot troubleshoot the voltages in the circuit. :( Anyway, I hope I help you find something. Good Luck!
 
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I checked the resistance of the 2 different windings on the yoke and they are close to another monitor I have here in the garage.

1. Do we know the "values" the 6100 yoke is supposed to put out?

2. Is there a good way to test the yoke that I don't know about?

3. Can I put a bare yoke on a piece of wood and plug it into the deflection board and power up the circuit without blowing anything? That is, no tube?

4. What order would you plug in the power and deflection transistors to test each circuit?

5. Does the yoke have to be plugged in to test the deflection board or will I cause Magic Smoke to leak out of something if I leave the yoke unplugged?

Some of these questions may seem pretty basic but that is the kind of guy I am. Very basic. Until then, I'm going to try another monitor with the same boardset to see WTF is going on. I'm running out of 3 amp fuses.

I didn't respond to everything.

1. See previous post.

2. See previous post

3. Absolutely.

4. J100 first, then J700 (because it has the spot killer), J600 in that order....

5. Nope. All it does is create a magnetic field and doesn't have to be on the tube.

-VJ
 
This was a known good working monitor and then it quit for some reason. All the transistors are still in their same spot after testing good. I'll go look at it again AFTER I work on a different monitor just to make sure I am not screwing up. I've read so many of my notes over the past few days I'm starting to get a little Vector Crazed if there is such a thing. Oh yeah, my values on the yoke are just about the same as yours.
 
This was a known good working monitor and then it quit for some reason. All the transistors are still in their same spot after testing good. I'll go look at it again AFTER I work on a different monitor just to make sure I am not screwing up. I've read so many of my notes over the past few days I'm starting to get a little Vector Crazed if there is such a thing. Oh yeah, my values on the yoke are just about the same as yours.

Ok, I re-read what you posted. Are you connecting P101? How about the spot killer Blue/White cable? You said you were not connecting the HV, but don't know if you were just not connecting the cable to HV cage, but connecting P101 to the deflection PCB and neck board? What about the molex connector off of the HV cage to the neck board? Just trying to figure how how much your connecting when the fuses blow. Since it isn't the deflection board (you tried another board), it almost has to be in the wiring or neck board. You validated the yoke and transistors so there are very few placed left. Have you tried a new neck board?
 
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See, here's where a completed thread with details of the fix would've come in handy. Le sigh.
 

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Yeah. Back then I was gone a lot and stuff would sit for a long time before I could work on it again. When I did get it working it usually needed to go out right away. I'm sure I probably figured it out. Let me go dig thru my notes and see if I recorded how I fixed this bad boy. 2009 huh? Wow.......

OK, checked my notes and they only go back to 2011. I know I have another notebook around with some notes in it. Let me dig around and see what I can find. I'm heading out of town for a week so you might find the answer before I get back to you. You might check the diodes under the big white resistors.

pat
 
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Was a solution found for this? Have the same thing going on right now and a few narrowed down areas to troubleshoot would be great.
 
Thanks Ian - will start checking components tonight!

On a side note - when will you have the pole position power wiring kits available?
 
usual suspects for F600 and F700 failure are Q603,Q604, Q605, Q606 for F600
and F703, F704, F705, F706 for F700

I'm having this issue with F600 and F700 blowing and have yet to find an answer, although I haven't tried everything yet such as testing the yoke.

I tested the transistors in circuit, and their readings were all similar, then I pulled Q603 to test it and it tested fine. I assumed then that they were all probably good. Found a bad diode at D602 and replaced it, 1N4001.

All my chassis mount transistors are new, and the game has been working great for a while till this just happened. I've rebuilt most of it with the twisted quarter K6100 repair kit, new flyback, new HV pot, resistors etc...

Going to try measuring the yoke now.
 
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I'm having this issue with F600 and F700 blowing and have yet to find an answer, although I haven't tried everything yet such as testing the yoke.

I tested the transistors in circuit, and their readings were all similar, then I pulled Q603 to test it and it tested fine. I assumed then that they were all probably good. Found a bad diode at D602 and replaced it, 1N4001.

All my chassis mount transistors are new, and the game has been working great for a while till this just happened. I've rebuilt most of it with the twisted quarter K6100 repair kit, new flyback, new HV pot, resistors etc...

Going to try measuring the yoke now.

Did you disconnect the headers for the frame mount transistors and test them with your meter in diode mode to ensure they are good and not shorted to the frame? Did you re-flow the headers? Below is my cheatsheet I made a long time ago for how to test the transistors. Doing it this way rules out the mounting, wiring as well as the transistor itself.


NPN (2N3716) Test on connector at Pin positions 1, 3, 4 of J100, J600, J700
===============================================

Test #1
-------------------
Red -> Pin 3
Black -> Pin 4

Result: .45v to .9v

Test #2
-------------------
Red -> Pin 3
Black -> Pin 1

Result: .45v to .9v

Test #3
-------------------
Red -> Pin 4
Black -> Pin 3

Result: Open

Test #4
-------------------
Red -> Pin 1
Black -> Pin 3

Result: Open

Test #5
-------------------
Red -> Pin 1
Black -> Pin 4

Result: Open

Test #6
-------------------
Red -> Pin 4
Black -> Pin 1

Result: Open



PNP (2N3792) Test on connector at Pin positions 5, 6, 7 of J100, J600, J700
===============================================

Test #1
-------------------
Red -> Pin 6
Black -> Pin 5

Result: Open

Test #2
-------------------
Red -> Pin 6
Black -> Pin 7

Result: Open

Test #3
-------------------
Red -> Pin 5
Black -> Pin 6

Result: .45v to .9v

Test #4
-------------------
Red -> Pin 7
Black -> Pin 6

Result: .45v to .9v

Test #5
-------------------
Red -> Pin 7
Black -> Pin 5

Result: Open

Test #6
-------------------
Red -> Pin 5
Black -> Pin 7

Result: Open
 
Thanks VJ! After testing them according to your awesome tutorial, I found issues with 4 out of 6 of them. WTH? What would cause them to go so relatively quickly? (a month or two of working well). Was it possibly because of the diode D602 that was fried? Or?

They were the ones connected to P100 and P600.
The P700 transistors tested perfectly.

I checked all diodes everywhere, but just did a visual on the resistors (many of which I already replaced) and nothing looks burnt.
 
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Thanks VJ! After testing them according to your awesome tutorial, I found issues with 4 out of 6 of them. WTH? What would cause them to go so relatively quickly? (a month or two of working well). Was it possibly because of the diode D602 that was fried? Or?

They were the ones connected to P100 and P600.
The P700 transistors tested perfectly.

I checked all diodes everywhere, but just did a visual on the resistors (many of which I already replaced) and nothing looks burnt.

Pull the ones that test bad and see how they test off of the chassis one at a time just to be sure something else with the harness or mount was the problem. Reflow the headers with your soldering iron. They are prone to get cold solder joints which can cause problems due to intermittent connections, etc.


Have you put a low voltage solution on the monitor like the LV2000/LV6100? If not you need to make sure your LV section is good. The schematics in the manual have the expected voltages for connector P100. So it is pretty easy to see if the LV section is putting out the right voltages.

So that is the order I usually do things.

1) Prove transistors and harness is good.
2) Prove LV is good.
3) Prove HV is good.

If all of those are good, you generally have some other symptoms to track down instead of blowing fuses, etc. Obviously if any one of those items isn't right, you have to drill down into it. There isn't much to LV if you put in a mod. The Mods do the whole job once they are in place. A HV rebuild is usually enough to fix issues there.

Good Luck!
 
Pull the ones that test bad and see how they test off of the chassis one at a time just to be sure something else with the harness or mount was the problem. Reflow the headers with your soldering iron. They are prone to get cold solder joints which can cause problems due to intermittent connections, etc.


Have you put a low voltage solution on the monitor like the LV2000/LV6100? If not you need to make sure your LV section is good. The schematics in the manual have the expected voltages for connector P100. So it is pretty easy to see if the LV section is putting out the right voltages.

So that is the order I usually do things.

1) Prove transistors and harness is good.
2) Prove LV is good.
3) Prove HV is good.

If all of those are good, you generally have some other symptoms to track down instead of blowing fuses, etc. Obviously if any one of those items isn't right, you have to drill down into it. There isn't much to LV if you put in a mod. The Mods do the whole job once they are in place. A HV rebuild is usually enough to fix issues there.

Good Luck!

Thanks again for the help. I have the LV2000 installed, and have reflowed the solder on all connectors, but will do them again anyhow. I've done the repair kit on it that included most problem diodes/resistors/Zenerdiodes/capacitors etc, and a new flyback, HV adjustment pot.

I'll pull the transistors in question and see what's happening with them. Thanks again for the info, I'll be back with my findings.
 
Thanks again for the help. I have the LV2000 installed, and have reflowed the solder on all connectors, but will do them again anyhow. I've done the repair kit on it that included most problem diodes/resistors/Zenerdiodes/capacitors etc, and a new flyback, HV adjustment pot.

I'll pull the transistors in question and see what's happening with them. Thanks again for the info, I'll be back with my findings.

If you reflowed the headers, you shouldn't have to do it again. I just didn't see a message from you stating that you did it, so I had to mention it again. You might just inspect them with a 10x loupe if you have one. After the transistors, start digging into the voltages then to see where the problem might be.
 
Just pulled the transistors in question and they all tested bad.
I have neck glow, but I don't get any reading for the 180v at the orange wire on neck board, or pin 5 on the HV unit. I have ground to chassis, meter set to 200vdc (even tried 500vdc) and I get a reading of .001 or something on both points. That can't be right if I have neck glow can it?
Both lights are on on the LV2000, no light on for spot killer, and no light on on the HV unit. (P329 version, deflection board is P327).

I tested the transistors for grounding out when I originally installed them, and they weren't loose when I removed them this time so I can't see grounding being an issue right? They worked great for a while.
Again, could that one diode that was shot have caused this? Seems like a stretch, and I wonder why the 2 transistors on P700 were fine in all this but the other 4 failed. Still blowing F600, F700.

I'm just going to go over the boards again and see if I can find any bad resistors etc. Thanks for your input.
 
Thanks VJ! After testing them according to your awesome tutorial, I found issues with 4 out of 6 of them. WTH? What would cause them to go so relatively quickly? (a month or two of working well). Was it possibly because of the diode D602 that was fried? Or?

They were the ones connected to P100 and P600.
The P700 transistors tested perfectly.

I checked all diodes everywhere, but just did a visual on the resistors (many of which I already replaced) and nothing looks burnt.

Ive had it where i installed new transistors, they all all test good.
fire the game up for a while and it started blowing fuses.
two of the transistors heated up and walked alittle then shorted to the frame.
 
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