G07 B+ won't adjust

the ic501 i have hundreds in stock new originals and you don't easily test the ic chips (i personally just replace with known good and socket it because my time is worth something, i don't test most ic if i have narrowed it down to a very high probability of an IC failure it gets replaced).

check the traces for cracks is only checking for continuity along all traces to find where you have a crack. i personally start out checking in the ohm mode with the beeper so i don't have to watch the meter constantly, BUT unless you have a full break you will be rechecking because the beeper will beep even if you don't have perfect continuity, so use your preference.
 
Ah, I see. Sure, I'll do a full PCB trace continuity check, it should not take too long. I'm looking on your website for an X501 replacement too, do you have any? If so, what is the part number?
 
Ah, I see. Sure, I'll do a full PCB trace continuity check, it should not take too long. I'm looking on your website for an X501 replacement too, do you have any? If so, what is the part number?

x501 is a 2sc2610 or 2sc1507. pm me if you need them.
 
First lets back this train up. When you say the monitor powers up are you getting heater glow and raster? If not the monitor is still dead and not powering up.

With a 160 Volts at the HOT and X701 removed and you get no heater glow or raster you have a horizontal deflection problem. The 6 most common culprits or components for horizontal deflection problems on this chassis are these and they are in no particular order. Here they are IC501 C511, X501, X01, T501 and T502. Then if all of those parts are good it is a broken trace or cold solder joint.

You can check T501 with out removing it from the board. You should get a short on both the primary and secondary of the transformer. Any thing more than a short, it's bad. I don't recommend removing it unless you are very careful. You can break the connections on the legs inside the transformer. Once you do that it is no good. There is no reproduction of this part.

I have actually been able to solder a few T501's back together. However it is not an easy task.

Ed
 
what about the width coil?? couldn't that be a cause also on horizontal deflection issue?
 
@Ed, I was not powering up long enough to see if the screen would warm up since I did not want to blow out another FB. However, I just turned it on and let it warm up for a minute with the lights off. No neck glow, no visible raster. HOT has 160V on it.

This is the status of each:

T502: New, just replaced for the second time in case the previous new one failed.

X01: New, just replaced.

C511: New with the re-cap, pulled and bench tested with capacitance meter.

T501: Pulled (carefully) and bench tested. 55 ohms on one side, 0.5 ohms on the other. Compared to T501 on a spare PCB I just picked up, it had the same readings. Maybe both T501s are bad?

X501: Just ordered new transistors. Swapped with X501 from spare PCB, but that may be bad as well.

IC501: Just pulled and installed a socket. Swapped with IC501 from spare PCB. Same scenario as X501, could still be bad since I don't know the history of the spare PCB. Ordered new IC501, waiting for it to arrive.

Started checking PCB traces from FB outwards. Found nothing yet. I suppose I can also just rework every solder joint to be sure, but they all look good under the 10X loupe.

I have also replaced the VR, and pulled and bench tested a lot of resistors. So far there is not smoking gun.

I do not remember the status of the Width Coil, i.e. I don't know if I have replaced it. What should it read out of circuit? I'll order a new one just for the hell of it.
 
what about the width coil?? couldn't that be a cause also on horizontal deflection issue?

I have actually powered up a GO7 with out the deflection yoke fully plugged in. What I got was horizontal collapse. Also one time all I got was a dot in the center of the screen.
 
@Ed, I was not powering up long enough to see if the screen would warm up since I did not want to blow out another FB. However, I just turned it on and let it warm up for a minute with the lights off. No neck glow, no visible raster. HOT has 160V on it.

This is the status of each:

T502: New, just replaced for the second time in case the previous new one failed.

X01: New, just replaced.

C511: New with the re-cap, pulled and bench tested with capacitance meter.

T501: Pulled (carefully) and bench tested. 55 ohms on one side, 0.5 ohms on the other. Compared to T501 on a spare PCB I just picked up, it had the same readings. Maybe both T501s are bad?

X501: Just ordered new transistors. Swapped with X501 from spare PCB, but that may be bad as well.

IC501: Just pulled and installed a socket. Swapped with IC501 from spare PCB. Same scenario as X501, could still be bad since I don't know the history of the spare PCB. Ordered new IC501, waiting for it to arrive.

Started checking PCB traces from FB outwards. Found nothing yet. I suppose I can also just rework every solder joint to be sure, but they all look good under the 10X loupe.

I have also replaced the VR, and pulled and bench tested a lot of resistors. So far there is not smoking gun.

I do not remember the status of the Width Coil, i.e. I don't know if I have replaced it. What should it read out of circuit? I'll order a new one just for the hell of it.

With out physically seeing the chassis now, I'm out of ideas.

Like i mentioned before if you get to the point where you want a second set of eyes to look at it PM me. We will work something out to get this chassis going.

Ed
 
@Ed, I was not powering up long enough to see if the screen would warm up since I did not want to blow out another FB. However, I just turned it on and let it warm up for a minute with the lights off. No neck glow, no visible raster. HOT has 160V on it.

This is the status of each:

T502: New, just replaced for the second time in case the previous new one failed.

X01: New, just replaced.

C511: New with the re-cap, pulled and bench tested with capacitance meter.

T501: Pulled (carefully) and bench tested. 55 ohms on one side, 0.5 ohms on the other. Compared to T501 on a spare PCB I just picked up, it had the same readings. Maybe both T501s are bad?

X501: Just ordered new transistors. Swapped with X501 from spare PCB, but that may be bad as well.

IC501: Just pulled and installed a socket. Swapped with IC501 from spare PCB. Same scenario as X501, could still be bad since I don't know the history of the spare PCB. Ordered new IC501, waiting for it to arrive.

Started checking PCB traces from FB outwards. Found nothing yet. I suppose I can also just rework every solder joint to be sure, but they all look good under the 10X loupe.

I have also replaced the VR, and pulled and bench tested a lot of resistors. So far there is not smoking gun.

I do not remember the status of the Width Coil, i.e. I don't know if I have replaced it. What should it read out of circuit? I'll order a new one just for the hell of it.

Did you ever get this resolved? Been chasing a ghost on my GO7 as well and looking for ideas.
 
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