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Mitsubishi CT-36309 36" CRT Issues
Another curbside refugee I took pity on, mostly because I have heard a lot about these larger Mitsu CRTs but never had one. It's pretty clean and appears well cared for. When plugged in, the power supply clicks continuously. After several seconds I noticed a thin whisp of smoke from what I thought was the flyback and unplugged immediately. As it turns out, the flyback was not to blame; it was instead emanating from a small disc capacitor(?) very near the FBT, dead center in the attached photo. Obviously something upstream is causing this cap to throw a tantrum, but what?
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Sony Trinitron Fan |
#2
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The capacitor might be the only problem. This looks like one of the capacitors that connects between the collector of the horizontal output transistor and ground. This capacitor is under a lot of stress and these little blue capacitors are bad about shorting and burning. Replace the capacitor and the set will likely work again.
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http://www.youtube.com/user/radiotvphononut |
#3
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I would be very happy if that little guy ended up being the only problem! I assume the ratings will be printed on the cap, but as it isn't an electrolytic, it may be some sort of code rather than a plain English rating. Will pull it out and check when I get a chance. Hopefully the rating hasn't been burned off!
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Sony Trinitron Fan |
#4
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The model number is not listed in Sam's; so, hopefully, the value will be on the capacitor.
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http://www.youtube.com/user/radiotvphononut |
#5
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I have extricated the offending capacitor. It's nice and toasty, haha. I can read the following on its side:
HR R 561K __KV Unfortunately the cap is burned over part of the rating for KV. The last digit may be a '2'. The capacitor's location on the board is C568.
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Sony Trinitron Fan |
Audiokarma |
#6
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I KNOW a 2KV cap would work fine here.
I have repaired many tv's over the years...of ALL sizes...includiung projos--for this problem. nearly ALWAYS....that is all that is wrong--besides maybe a fuse or possibly fuse resistor on the line open or such. |
#7
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Now, my only question is how to interpret '561K'. I've mostly dealt with can electrolytics, so am unfamiliar with this nomenclature.
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Sony Trinitron Fan |
#8
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561K is a 560 pf. Probably rated at least 2 KV.
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http://www.youtube.com/user/radiotvphononut |
#9
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Here is an ebay seller--US--for this cap. 10PCS.
http://www.ebay.com/itm/10PCS-2KV561...item20fd98c37f |
#10
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Quote:
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Audiokarma |
#11
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Quote:
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Sony Trinitron Fan |
#12
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Another question: How critical is the capacitance rating? I have some junk/parts boards laying around with very similar caps on them. Just an idea that may save me some time and money.
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Sony Trinitron Fan |
#13
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You need to use the same value as the original, if at all possible. This capacitor controls the HV and the width of the picture.
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http://www.youtube.com/user/radiotvphononut |
#14
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Very common fail on 1980's - early 90's sets. Mostly in
MGA, Panasonic, RCA, Quasar, Sony & Panny built GE's. Usualy all thats wrong. On Panasonic & Quasar VCR combos it causes a chain reaction & blows the HOT, STR regulator & a few resistors. IIRC most used 220pf. On any sets of this vintage is best to give a good looking at the hoz drive through the hoz out for cracked caps & cold joints. 73 Zeno |
#15
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There were some late '90's Philips-Magnavox sets where the blue capacitor would short. I remember the 19" Panasonic-built MK chassis GE's that used an orange capacitor that would burn and this would sometimes take the HOT with it.
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http://www.youtube.com/user/radiotvphononut |
Audiokarma |
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