G07 Issues

Scucci

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Anywho, I said I wanted to do this one from Fromms flowcharts... but it comes to a point (at the end) where I just can't decide on what to do.

Anywho, monitor had no neck glow... followed the charts and tested R1, voltage was about 25V too high on either side of the resistor (167V, 145V). So, next step was removing X701... K, neck lit up, I have a "picture" (no boards hooked up) on the monitor now... Great. I check the voltage again... it's gone down, but still about 15-20V too high... lets look at the two options.

1: Monitor now works
or
2: Voltage still too high

Okay... yeah, monitor "works"... k, but the voltage is still too high...

FWIW X701 was open all the way around.

Anywho, so the screen turns on now, and after I turned the brightness down on the flyback, there's a wavy black/brown spot on the "top" (left) of the monitor... *image attached*

Caused by... bad caps? The fact that transistor is still off the board? Flyback pooping out?

What's my next step in this thing?
 

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I remember getting a picture and too high of a voltage with X701 removed when I had the voltage regulator (C1106) wired up backwards. Check yours for proper wiring and function....
 
KK, I just worry about wasting a cap kit if there's something majorly wrong with the chassis.

Either way, X701 was completely screwed, so I'll order in a replacement for it while I'm all it. I'll cap it, replace the transistor and then report back...
 
Its never a bad thing or a waste to put in a cap kit, while you are at it do the fly , chances are it will pop on you. GO7 is not a monitor to go component by component, they have notoriously weak flys and they take HOTS out with them
 
I went ahead and pulled that transistor off another chassis, tested it, and slapped it on the bad chassis, no chage from when the other chassis had that bad X on it. Just coincidence that it happened to be bad. Ordering my capkits (back ordering for my other monitors as well) Hopefully she'll be good to go in a couple of days.

I played a quick game on the bad monitor (about 3 mins just to see the 1st intermission on MsPac). But is there any long term damage that could be done by operating the monitor with that (X701) transistor missing?
 
C1106 refers to the 2SC1106 power regulator

Ahhhh... KK, two part confusion on my end. The caps are listed in the manual as C1XXX so it was throwing me off... second part is the can isn't listed as that in the manual. lol Sorry about that.

It seems to be wired up properly, and I'm getting good voltage on the top of the can (160'sh)... is there anything else I should check with it?

EDIT: That's also cross-reffed at NTE94, sound about right? Just in case there is something wrong with it in the end. (Might just order one anyways...)
 
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Ahhhh... KK, two part confusion on my end. The caps are listed in the manual as C1XXX so it was throwing me off... second part is the can isn't listed as that in the manual. lol Sorry about that.

It seems to be wired up properly, and I'm getting good voltage on the top of the can (160'sh)... is there anything else I should check with it?

The 160 should actually be about 145. What's it read on the other side?
 
If you are reading 160 on both sides of the big white resistor, then I'll bet your VR is either bad or wired wrong. I wired one wrong by accident once and got the exact same readings.

Here's a pic of how it should be wired...

g07r-15.jpg
 
Oh, by other side I thought you meant the other side of the chassis (the other big trans). I'm reading 166'sh on one end and 145 on the other end of the resistor.

The machine was in a waiting room at a pediatrics center looked over by a lady that didn't even know the coin door was supposed to open. I doubt she was doing much chassis work. ;p

She said it was working fine for the longest time, then one day it just didn't come on (the monitor). So I don't think the wiring got screwed up, just something failed on me. I've got the cap kit, transistors (including the big boys), and some other misc crap I needed, on order... so hopefully I'll know by next week if I'll get anything out of it. I do have some spare G07 chassis (what the plural? Is that it... is it like sheep?) laying around here but they're from 19" monitors and I'm not sure how it would handle having one of them swapped over to it.
 
Probably have cold solder joints that need to be touched up, but a cap kit won't hurt...
 
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