K7400 - No B+

Its possible to put a replacement ic in wrong Looks like it was touched.
confirm its in correctly.
Then get manual or datasheet and find pinout, measure the Dc at the Vcc pin.
confirm its there.
After a few minutes touch heatsink see if it gets warm at all?
Ic would suspect IC or Voltage to it. Mention the V-Ic number
Some things to try.LUK
 
Update on this. I was able to fix the vertical deflection by replacing R402.

I have picture now, but missing color. On to the next step :)

PXL_20250112_220224124.jpg
 
Lee sent this to me for repair. I didn't have any color issues but I did have the same vertical deflection issue. Turned out to be an open R613. Never seen that before. Replaced R613 and it's back in business. Looks and works great. Lee will have to see if maybe the tube is the issue or maybe the harness/dip switches on the TPG that's being used might be turned off. On my end, I experienced no color issues. Got everything dialed in with no issues. Now, I will say that the replacement R402 that was installed was insufficient. It was getting way too hot. Replaced it with a much beefier one. Good to go now. It was also 4.0 ohms when it was supposed to be closer to 1.2. I had to fix a number of bad/lifted pads as well as remove a solder bridge on pins 2 and 3 for the remote board headers. I also found a 50v 10uf cap installed on the neckboard at C507. Installed the proper 50v 100uf. After all that, it's good to go.
 

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