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CRT (Makvision) image is a large bluish blob. Dead, or repairable?
jennifer:
Well I guess Jenn ment to say if someone moved the yoke, or the rings thay would throw off convergence, not if you physically moved the cab
...My guess it is the chassis is where your problem lies, most likely the flyback itself, or something associated with it.
Zebidee:
First you need to check blue colour drive circuit like grantspain suggested (several times) as a short there can cause an excess of the colour concerned - disconnect and see what happens. For example check/desolder the blue colour drive transistor or CRT pin (on CRT neckboard).
Baldbull:
I removed the two transistors on the blue gun circuit.... and no change.
Is it terminal?
Zebidee:
--- Quote from: Baldbull on February 15, 2021, 04:26:27 pm ---I removed the two transistors on the blue gun circuit.... and no change.
Is it terminal?
--- End quote ---
No - it is normal for a colour to come full-on when there is a problem in that colour's drive circuit. If there is no change after removing the transistors, it further suggests that is where the problem is.
You can test the transistors with a multimeter (there are a bunch of guides out there).
Alternatively, try swapping them with the equivalent transistors on the red circuit. If your problem becomes mostly red instead of blue then you know where the problem is.
If that gets you nowhere then desolder the blue pin on neckboard at the CRT socket and see how that looks.
Baldbull:
Unfortunately I hosed one of the transistors on the removal... So a true swap isn't an option. It's been a long, long time since I've done this kind of work. ~20 years.
The one transistor that survived tested fine. I can attempt to test the other... may be enough of the prongs left, but it's not reusable.
Don't think I can truly desolder that blue pin without getting a good solder sucker... this copper wick isn't cutting it and is likely how I split the transistor in two.
To be continued... maybe.