G07 Comes up bright and washed out w/raster lines...

retroACTIVE

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G07 Comes up bright and washed out w/raster lines...

and the thing is screaming, then within a minute or so it begins to shut up and the picture comes into focus and everything looks great...

1. Recapped
2. New flyback
3. New B+ filter cap
4. B+ adjusted to 120VDC

- I've not replaced the HOT

Difficult to tell where the screaming is coming from... sounds like its coming from around the focus assembly or even the transformer that is next to the flyback...

I suspected the original flyback to be the issue... but I replaced it with a new one from Bob and still same screaming when powered up from cold.

Its strange... it really does stop yelling eventually after it warms up and the pic does look good.

Any thoughts?
 
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With any monitor of this vintage, going over - at minimum - the common solder joints that break, and at best, ALL of them, is necessary. I'd start there.
 
Good. A lot of people just install the caps and call it a day, then wonder why there are still issues.

Get a paper towel roll and put it to your ear to narrow down where the whine is coming from.

Also try resoldering the joints behind the screen and focus adjustment knobs. I've had several lately that were very suspect.
 
Good. A lot of people just install the caps and call it a day, then wonder why there are still issues.

Get a paper towel roll and put it to your ear to narrow down where the whine is coming from.

Also try resoldering the joints behind the screen and focus adjustment knobs. I've had several lately that were very suspect.

Oooh thats a good idea! I was thinking about using a microphone with a scope to probe for the source but I like your idea better.

The one thing I'm certain I didn't check were the joints under the boots, thanks for reminding me.
 
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Any G07 that is rebuilt should have the original flyback replaced before it blows up.

Your whine is coming from one of two places - your flyback or your horizontal oscillator. Bob Roberts has a thing about how to make it stop...

http://therealbobroberts.net/whiny.html

Now, sometimes what you hear is actually coming from a poor solder connection on the back of the focus/brightness knobs...
 
Any G07 that is rebuilt should have the original flyback replaced before it blows up.

Your whine is coming from one of two places - your flyback or your horizontal oscillator. As your B+ is good, I'd suspect the flyback. Bob Roberts has a thing about how to make it stop...

http://therealbobroberts.net/whiny.html

Now, sometimes what you hear is actually coming from a poor solder connection on the back of the focus/brightness knobs...

I did see that on Bob's site however I already replaced the flyback with a new one though. When I first rebuilt the chassis I didn't change out the flyback... it was noisy so then I figured "must be the flyback" so I replaced it with the new one... same issue.

I'm definitely going to check the connections on the focus/brightness assembly tonight.
 
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