G07 Too bright

jumpman

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Donor 2012
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I got a completely rebuilt chassis from chris in MN. It worked fine after I installed it but after a few days I powered it up and it was too bright so I adjusted the brightness on the flyback it looked a little better. The next day I powered up and it was way too bright again however the screen adjustment on the flyback is as low as it goes. Besides being too bright the lettering and objects on the screen appear to have a shadow effect, Im not sure if the term is "bleeding" or not.

I adjusted the b+ to 120.0, tried adjusting pots on neckboard, flyback

Is there another adjustment on the chassis or yoke to adjust brighness?

I thought I would try that before I try a different chassis, any help or advice would be great.
 
I'd be leaning toward faulty flyback. Especially if the brightness on it has already been turned down all the way.

It did have a brand new flyback installed, but I suppose even a new one could go bad. I looked at a manual for the g07 but didnt see any other adjustments to try. If anyone knows of another adjustment let me know.
 
Just this week alone I've read on this forum about at least four different brand-new bad flys. Two K7000s, one K4900 and...something else, can't remember. Those aren't good odds.
 
It's possible your tube is faulty, with a heater short which could cause an overly bright picture. Do you have another G07 around that you could test the flyback with?

Have you asked Chris about it?
 
I have another g07 in my MC that works great, I was thinking I will try swapping the chassis to deterimine if its the chassis or tube, since it doesnt seem like there are any other adjustment pots for the brightness. I didnt ask chris about it yet since I wasnt 100% sure what the problem is yet, I have got 3 g07 chassis from him and have been very happy with his work and the fast shipping, I order and it arrives the next day, it doesnt get any better than that.

It's possible your tube is faulty, with a heater short which could cause an overly bright picture. Do you have another G07 around that you could test the flyback with?

Have you asked Chris about it?
 
I would definitely try it on another chassis to rule that out. If it happens with another chassis on the same tube, you've got your answer.
 
I've seen this happen when the SCREEN or FOCUS pot goes bad or start "leaking" to the adjacent pot. Even a new flyback won't help that, since a new fly doesn't come with those. (although a new flyback is ALWAYS recommended)

You can pull the little gray boots back and de-solder the wires from it and just swap that piece out and see what happens.
 

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There's also a chance it could be the beam limiter circuit.....check D301/D508/X303.

Edward
 
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