WG 19K7601 no neck glow

debaser138

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I've got a WG 19K7601 that was working but the focus was drifting. It had an original flyback with the white knobs. So I replaced the flyback and did a cap kit as well with parts from Peter @ arcadepartsandrepairs.com.

Now when I fire it up I've got HV and screen static but no neck glow and obviously no picture. I checked the VR and it's good. Someone previously put in an STR3130. I'm getting 130v at R301 from the furthest end of the tube and 165v at the end nearest the tube. I'm also getting 130v at the neck board.

Sounds like an issue with the heater circuit but everything looks good. Anyone seen this before? Any ideas what I should be looking at?
 
R213 is the resistor on the neckboard for the heater. do verify that the black ground wire that runs from the neckboard down to the frame on the deflection board is connected... though if it wasn't you wouldn't have any voltage at the neckboard. a curious tale. :)
 
verify that the black ground wire that runs from the neckboard down to the frame on the deflection board is connected... though if it wasn't you wouldn't have any voltage at the neckboard.

The thick black wire is ground only for the heater and G1. The RGB amp circuit is independently grounded by one of the wires in the 5-pin connector.
 
In looking at the schematics for the K7000, it appears R213 on the neck board should be 68ohms, not 8ohms. I though that the resistor was labeled 6.8 but perhaps I read it wrong. I'll need to look ok at it closer when I'm in front of it again.

EDIT: I just looked at the neckboard and R213 on this K7601 is a .68ohm resistor, which is measuring .8ohms in circuit. The PDF scan I was looking at made it hard to see the period in front of .68 ohms.
 
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I've got 12v on the neckboard at P202 pin 1 and 130v at Pin 3. Where is an easy place to test for 24v? Is one of TP points on the chassis 24v?

The 24v line should be pin 4 on the flyback and I think you can test it at the IC3 pin 6.
 
A handier place to test 24V is R83:

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If 24V is present and you doublechecked continuity from pin 9 of the flyback to R213 on the neckboard, then it would appear that there's no heater voltage coming out of the flyback and you should get another or put the old one back in. Broken filament in the CRT is a remote possibility but check that too.
 

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