Build Your Own Arcade Controls Forum
Main => Monitor/Video Forum => Topic started by: Vilepickle on October 05, 2015, 02:22:02 pm
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I repaired a 25" k7000 chassis board recently. In another 25" machine, I decided to try the chassis since its chassis was also a k7000, or one that looked almost identical. It worked for a little while, but I definitely had arcing inside the tube so I think the tube was a mismatch for this particular chassis.
My question is... what typically blows out if you get too much arcing like this in a tube mismatch situation? I definitely blew something out but I'm not sure what it was. I've replaced the flyback, C36, D18, HOT, and IC4 since but it's still not coming back to the state I had it. The HOT, IC4, and D18 definitely didn't read right. I did a cap kit right before it blew so it's also possible I need to re-cap kit.
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there shouldn't be ANY arcing in or outside the tube.
likely a neck fracture allowing loss of vacuum.
with any luck, the spark gaps did their job and didn't allow damage to cathode drive circuitry (video)
a hard arc can cause a Hout xistor short. which, in turn , may overload the power supply producing damage there.
most modern SMPS units will go into a protection mode during a high current condition averting serious supply damage
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By power supply do you mean the actual cabinet power supply? The cab this happened in is running fine after I fixed its normal chassis now. The chassis that blew is still not working but I was going to replace many of the diodes in the early circuit soon as the next thing.
When I first blew it, I replaced the HOT only. I heard a brief second of high voltage starting to happen and then it stopped. Perhaps I blew the HOT again? Since then I've done those other components and a few were indeed not reading correctly. But it is still blowing fuses.
I've heard about the high voltage shutdown due to XRAYs and all the regulations. Would I need to do anything to get the chassis out of this "state" other than replacing components like I'm doing?
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was referring to the monitor's onboard power supply.
sry, i tend to forget not everyone speaks tech
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No problem, I speak some but I'm still learning monitor stuff :) Obviously, since I was dumb and blew this chassis with a wrong tube.
By power supply do you mean everything in circuit leading before high voltage? That's what I've been assuming so far and targeting my replacements at.
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I fixed this, I ended up blowing the HOT again since I didn't have D18 or IC4 replaced at the same time. Woops :)