k4900 issue once more.

Xomb2e

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My chassis was working okay with some minor issues before cap kit. I installed a k4900 kit from Bob Roberts. I have HV but no neck glow. After the initial startup and diagnosis I noticed smoke and quickly powered it down. What parts should I be looking to replace and what could my problem have been? Rectifying diodes? I checked and double checked that all cap polarities were correct as this is my first attempt at a cap kit.
 
Did you try to see where your smoke was coming from? Was the yoke connected improperly? If you're not blowing a fuse, check the B+ and report back. If you continue to smoke, look to see where it's coming from.

And check all your caps. Maybe you put one in backwards and it blew on power up. Or maybe you have a solder bridge near one you did...
 
Did you try to see where your smoke was coming from? Was the yoke connected improperly? If you're not blowing a fuse, check the B+ and report back. If you continue to smoke, look to see where it's coming from.

And check all your caps. Maybe you put one in backwards and it blew on power up. Or maybe you have a solder bridge near one you did...

Checked and double checked cap polarities, no problem there. And no bridged connections. B+ at TP91 is 127.8VDC(black lead on frame red lead on TP correct?).

Reflowed input headers at neckboard and video input on chassis just for shits. Also, no smoking components this time around. Thanks for the suggestions you guys. Not sure where to go from here. My post count is properly a direct reflection of my knowledge but I'm learning.
 
It almost looks like there's a hairline crack in the glass on the neck of the tube. Im assuming this could be my problem. Can I meter out the yoke without a HV probe to make sure the correct voltages are making it to the tube?
 
no post a pic of said crack.

the tube and yoke are two different pieces. they are not connected in any way except where the neck board connects and the anode.

the tube is sealed and cannot be fixed if broken.

also update your general location in your profile and maybe some one local can come help.

Peace
Buffett
 
no post a pic of said crack.

the tube and yoke are two different pieces. they are not connected in any way except where the neck board connects and the anode.

the tube is sealed and cannot be fixed if broken.

also update your general location in your profile and maybe some one local can come help.

Peace
Buffett

Here is the suspect crack
 

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looks like glue and a scrach to me.

take a razor blade clean it off then Windex it and see what it looks like.

is there a blue/purple sparking in the neck when you turn the game on?

if there is the tube is shot. but if there is not then it possibly needs a rejuve.

Peace
Buffett
 
No sparking when turning the machine on.
I don't know what the hell I did considering it was working fine beforehand.
 
No sparking when turning the machine on.
I don't know what the hell I did considering it was working fine beforehand.

Did you hook the wires back up correctly?

One time I recapped a K4600, and I hook the high voltage wires to the interface board (they were supposed to be going to the neckboard). Needless to say, I fried about 5 components on the interface board (it smoked, literally). After replacing the fried components, and hooking the wires up correctly it worked like a charm.

Just a thought.

Greg
 
Did you hook the wires back up correctly?

One time I recapped a K4600, and I hook the high voltage wires to the interface board (they were supposed to be going to the neckboard). Needless to say, I fried about 5 components on the interface board (it smoked, literally). After replacing the fried components, and hooking the wires up correctly it worked like a charm.

Just a thought.

Greg

Wiring is correct. Found broken trace and jumpered it but still no progress.
I'm killing myself then moving to Alaska.
 
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