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25"CGA Makvision by Wei-Ya Monitor questions
lilshawn:
tick tick tick, is an indication that the B+ is overloaded and the SMPS power supply is gone into protect mode. when it does this, it continuously tries to restart in case it was just a fluke from having to recharge filter capacitors.
probably wouldn't hurt to do a re-cap, they look like they might be original, in which case they are 20 some years old. but you might be looking at a HOT for it as well.
if you post what the actual monitor chassis number is (probably like a CH-666 or 2525 or something like that) i can see how the HOT is in circuit and tell you the best way to test it to see if it's still good or obviously blown out.
ScottyDutch:
Thank you, I appreciate all your help with this. I didn't see a CH number, but I attached a couple of photos of the back of the monitor. If you think it might be somewhere else, please just let me know.
lilshawn:
M3125
it's a makvision branded 95% clone of the CH666 chassis with a modified neckboard and a handful of different parts.
6 out of 10 times it's caps. the other 3 times a dead HOT (sometimes both)... and one, the stupid resolution detection IC.
check the HOT (powered off) by measuring resistance across the middle and right most legs (the collector and emitter) should read something OTHER than shorted together. not a definitive test, but rules out an obvious issue there. if it measures in 100's or 1000's of ohms, go ahead and replace all the low voltage electrolytic caps 100uf and higher and all the high voltage electrolytic caps. (or buy a kit)
that will probably get you going again.
if it's still doing it, replace the HOT. sometimes they test okay, buy fail under high voltage stress. it'll be a 2S5302 buy from a reputable distributor, not ebay.
if still not, could be one of the big high voltage orange/brown/blue polymer plastic dipped caps is shorted out. common failure mode is shorted so run around and test with your meter looking for one's legs connected when it shouldn't be. they should all read some resistance...not 0.
ScottyDutch:
Thank you, it looks like I have some work to do!
grantspain:
flybacks are failing on these in a big way now