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#1
08-06-2023, 12:19 AM
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Need help fixing Samsung Slimfit tx-s2783
Okay. So I noticed that there is wiggliness in the top 1/4th or 1/5th of the screen. It relaxes and gets less wiggly when things warm up. From my research, that's horizontal deflection. So I recapped all the electrolytics. Pretty much any CRT is due for that. The colors and geometry got WAY better afterwards. Not bad for my first CRT recap. But even though everything looks better, the GOD DAMN deflection issue is still there. So I said okay, maybe these big brown film capacitors adjacent to the flyback are on the Fritz. So I remove one. Can't tell what 125j is because I have no electronics knowledge, so I measure the capacitance with my multimeter. Comes out to 1.2uf. okay. About what I would expect from a film capacitor. So I move on to one labeled 644J 400V (the kind of voltage I would expect would have to do with something like deflection). The multimeter read 615 NANOFARADS... What the hell? 615 NANOFARADS!? That's a completely retarded measurement. It should be under 5uf. Is this a sign that the cap is bad? Should I pull others just to see what kind of measurements I get? The first one was fine... There are service manuals for some of these slimfits, but my model has not been posted. In the 30inch service manual i found, there were part replacement details. this is EXACTLY what I need to replace the film caps, but I still don't know if I'm tackling the right thing.
I don't know what I'm doing. I'm extremely overwhelmed. I'm glad the electrolytic recap worked and I didn't fail at that, but these big brown sawhorse film capacitors are ridiculous. I don't even know if it'll fix my deflection problem in the first place. PLEASE help! https://i.postimg.cc/sxvLSMWv/PXL-20...-201041560.jpg https://i.postimg.cc/KjwH5m7Q/PXL-20...-201031317.jpg https://i.postimg.cc/13pjph8c/PXL-20...-194505081.jpg You can see the wiggliness in the screen pic. Last edited by Bowlsnapper; 08-06-2023 at 12:40 AM. 
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#2
08-06-2023, 08:30 AM
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First check the main B+ that feeds the horz stage. Must be right on.
The PCB is probably marked. Typical 130 VDC. Those caps rarely go bad. Markings are the value, last number is zeros. Ex 623 is 62000 in mfd or pf. Caps around the hoz / HV are critical & must be the same values & type or you may blow things. Odds are its another 'lytic but check it for cold joints in horz and main power supply. good luck 73 Zeno  LFOD !
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#3
08-06-2023, 09:23 AM
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615nF is a reasonable measurement...that's 0.615uF. A bit low, but well within the 20% (I assume) tolerance of the cap.
__________________
When you lower your standards, you set a new standard.
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#4
08-06-2023, 03:49 PM
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I will have to replace the film caps in order to test the B+ voltage. Is it safe to assume that the film caps are not the culprit? Should I just leave them alone? I don't even know how to convert microfarads to nanofarads.. I guess just 1 into 1000. Not a huge deal. But I can't even find replacements for these caps anyway. The 615nf measurement freaks me out. I can find .56uf 400v film caps on digikey, but that's it. Somebody here is saying it 62000uf. There's no way. Should I just leave these alone? I'm suspicious of the nearby transistor that's supposed to handle B+.
Zeno: Every single electrolytic capacitor was just replaced, so it can't be that. Soldering is sound. 130v is indeed marked on the underside of the board. So I should test it while plugged in? Where should I attach ground, chassis? If it's too high then a component has no continuity, and if it's low then it's basically shorting, correct? Also... Which contact is the 130? I can't quite pinpoint it... I guess I can just move around with the meter, until I'm sure I've found it. It can't be THAT far off... The problem with my measurements is, I can't find replacements that match what I'm reading. The only way to get accurate replacements is by purchasing the service manual, the way I see it. But the film caps are probably fine. I believe my issue is elsewhere... Should I give some of these solder points a good reflow? https://i.postimg.cc/8zSz1Nwb/PXL-20...-203720386.jpg https://i.postimg.cc/fT4wKM4h/PXL-20...-203728977.jpg Last edited by Bowlsnapper; 08-06-2023 at 05:01 PM.
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#5
08-06-2023, 05:57 PM
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130 VDC apx while set is on.
Caps are in mfd, or pf. Asian sets use nano at times. Also US uses mmf at times, same as pf. Should be tons of sites explaining the conversions. Its been 10 yrs since I opened a set so I dont want to give you bad info. Before that it was 40 yrs of use & second nature. But age has effected the memory ! Keep in mind this set has 2 grounds. Hot ground is the primary of the power supply. The rest of the set is ( cold ) isolated. Use the CRT ground or tuner shield for this one. There will be different ground symbols in the manual. Zeno
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#6
08-06-2023, 07:44 PM
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Quote:
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#7
08-06-2023, 08:05 PM
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Well nothing matters now. I'm getting high pitched groaning when plugging in the set after I tried to reflow some solder points. Which is exactly what I was afraid of. Oh well! So much for that. Guess I'll throw that in the trash! So much for a successful recap, huh?
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#8
08-06-2023, 08:35 PM
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The howling is coming from the speakers. Tube warms up when speakers are unplugged. Speakers cause the tube to shut off. Will not get any display, however. Get plenty of static from the front.
I'm so PISSED. I should have just left it alone and ignored the deflection. Now I just wasted a bunch of time recapping and it worked fine... It's history. I'm never trying to reflow something again. From now on I'm just recapping the electrolytics and being done with it. What should I do, trash it? Last edited by Bowlsnapper; 08-06-2023 at 08:50 PM.
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#10
08-07-2023, 12:36 PM
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When you spot a bridged land, or suspect about, you can try to test it with a DMM to see if it was really shorted. Like John said, is common to this occur (even with experienced people).
And if after this check the speaker symptom continues, try to remove the audio output IC (if it uses a IC) and power the TV on, to see if it was damaged or not.
__________________
So many projects, so little time...
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#11
08-07-2023, 08:54 PM
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Quote:
Yup - do that..... If you get it working, then leave it alone. .
__________________
Yes you can call me "Squirrel boy"
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#12
08-08-2023, 06:02 AM
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Those tvs were pretty nice, I liked the Dynaflat sets better. But that ripple is most likely a bad capacitor. Could be power supply, or H-Output, and in some cases on newer sets like that, H-Output & power supply can be the same. Since the ripple is stationary, I would guess more towards a H-output Cap. You could try finding a service manual for it online even if you have to buy one, it may make it easier on you. Or you could just keep replacing caps till you get to the bad one... .
__________________
Yes you can call me "Squirrel boy"
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#13
08-10-2023, 09:33 PM
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Quote:
Last edited by Bowlsnapper; 08-10-2023 at 09:42 PM.
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Linear Mode
