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Hi Gurus!

I have a K7000 from my 1943 cabinet. The monitor worked and colors, etc. actually looked OK but it had never been serviced. The original white-knob flyback was cracked and focus was going in and out as the monitor would warm up (like it would start out of focus, then eventually drift in after a few minutes of running, and then eventually drift back out again and I would hear the flyback ticking every second or so. I bought a new flyback and cap kit from @security0001 at APAR, and finally got around to the job this weekend. This is my first time trying to service a chassis myself.

I washed the board carefully and dried it over a box fan for several days, then I started by reflowing the yoke and signal headers and all the big resistors according to this guide. Although the monitor was working before I started, I also checked the HOT and the rectifier diodes, following YouTube videos from Mike's Amateur Arcade Monitor Repair basically for practice. They all checked out.

I swapped all the caps after reviewing a cap map I found on this forum and verifying the polarity of all the existing caps. I also replaced the flyback with the new one from APAR. After complete, I re-checked all of the caps one last time and all were correct. This morning I reconnected the chassis to the tube, connected my bench power supply and TPG and fired it up. No picture 😖

I have HV. I can hear it, I can feel the static on the face of the screen. But no neck glow, and obviously no video output. B+ is 124V measured at the big ceramic resistor's blue lead. I tried the full range of the Screen knob on the new fly and no change. No raster at all. I turned out all the lights to make sure I wasn't missing it, but definitely no neck glow. But hey, nothing blew up! The shutdown pot is still epoxy'd as it had been originally, so I didn't adjust that in any way.

Any pointers on where to go from here? I can go over everything I did again, but I checked and rechecked all the parts I installed as well as the stuff I reflowed. I looked over the rest of the chassis for obviously damaged solder points and didn't identify any. At one point, I did try to adjust the angle of the leg on the diode right next to the yoke connector (D18 I think it is?) and the pad broke away, so I removed all the solder and bridged that leg over to the adjacent yoke connector pin since they were on the same trace and had continuity even after the pad pulled started to break.

Again, the monitor did work before I did my stuff to it, so something that I did definitely broke it. This is my first attempt at a recap or any "real" monitor repair, so definitely looking for some tips on what to check next.

Thanks!
Bob


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