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  #16  
Old 05-15-2018, 07:37 PM
Bill R Bill R is offline
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Almost always the capacitor. I would not just replace tubes. Most of them are probably fine. The new capacitor will be much smaller and can be mounted under the chassis. There likely other capacitors that will need to be changed as well.
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  #17  
Old 05-18-2018, 07:49 PM
Wind157 Wind157 is offline
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Well that was a bust. Replaced the capacitor from that can, just made another component smoke badly and vert didnt work at all until I removed the new capacitor. Unless I'm reading the SAMS and attached the leads to the wrong part of the can.
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  #18  
Old 05-18-2018, 09:36 PM
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init4fun init4fun is offline
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Um , you took a picture of the smoke ? Really ?

To save you future grief in your troubleshooting endeavors I'll make this short & sweet ;

At the very first hint of smoke , reach for the power cord to yank it outta the wall rather than the camera !
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  #19  
Old 05-18-2018, 09:56 PM
Wind157 Wind157 is offline
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I took a picture after I unplugged it so I could better identify which component was smoking.
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  #20  
Old 05-18-2018, 11:19 PM
Wind157 Wind157 is offline
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Well go figure, so no matter how I connect the new capacitor there is smoke. I disconnected a cable running to the can assuming maybe I was over powering the smoking resistor but still the same thing. When I disconnected the new capacitor and ran a clip from the disconnected wire the tv works fine.
Bad solder? Or dumb luck?
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  #21  
Old 05-19-2018, 10:45 AM
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Does that yellow wire connect to ground or pass thru the chassis to something on the other side in the third pic? Did you observe polarity with the new capacitor, if you connected it with reverse polarity it would pass enough current to smoke a resistor (the capacitor will also be damaged by powering it up with reverse polarity).

Sams is good, but has typos. Always best to learn to read the markings on the part and verify the actual wiring of the set.
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  #22  
Old 05-19-2018, 02:11 PM
Wind157 Wind157 is offline
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The yellow wire connects to another yellow soldered to a tube then the the vert control.
The new capacitor didn't have an indication of polarity but connecting either way didn't make a difference, it smoked that resistor either way.
That said it worked fine after disconnecting the new capacitor and the image filled the screen where it did not before so I assume the yellow wire was my problem. Unless the power of Jesus flowed into the smoking resistor.
This morning the image still fills the screen even the bottom portion that it didn't not prior to trying the new cap except I can't adjust the picture in any more. I assume the smoking resistor is now my problem but at least I can see what that is and where it connects unlike the cap from the damn can.
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  #23  
Old 05-19-2018, 03:08 PM
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There should be polarity on the new cap unless you bought unpolarized (but those are not common over 50V rated). If you connected the cap backward the first time then it probably shorted instantly on power up and correcting the polarity after that would not have helped...Once a cap shorts it is dead. You only get one chance to connect a lytic with the correct polarity before power up, before destroying your new replacement...Worse yet if you connect a lytic backwards it can explode and possibly cause injury...Measure twice cut once (ie make sure it is right before power up even if you have to ask us).

Where are you sourcing your caps? You should be going with a legitimate online vendor of NEW capacitors. Places like Mouser, Digikey, Allied, Justradios, Capacitor World, etc are where you want to buy from...Brick and mortar shops who's stocks can languish years to decades, and used parts places like surplus stores are bad sources...Electrolytic caps have a shelf life shorter than their rated life...Lytics need to have voltage applied to them regularly or they go bad...I've personally bought dead caps from Radio Shack and surplus places in the past, but I had a quality capacitor tester at my disposal to realize it and not use those parts.

Electronics are not magic, and while I can appreciate faith, it will not keep the original caps or bad quality replacements going for long.
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  #24  
Old 05-19-2018, 03:11 PM
Wind157 Wind157 is offline
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The faith comment is sarcasm as the cap didn't resolve the issue yet that issue is resolved. Now I have to replace smoky resistor
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  #25  
Old 05-19-2018, 03:17 PM
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Quote:
Originally Posted by Wind157 View Post
The faith comment is sarcasm as the cap didn't resolve the issue yet that issue is resolved. Now I have to replace smoky resistor
Got a DMM and can do math? If so it won't hurt to check the original...If it is still within tolerance then you did not let out too much smoke.
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  #26  
Old 05-19-2018, 03:26 PM
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Kevin Kuehn Kevin Kuehn is offline
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Can you please post up a picture of that new cap you had installed?
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  #27  
Old 05-19-2018, 04:00 PM
Wind157 Wind157 is offline
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Quote:
Originally Posted by Electronic M View Post
Got a DMM and can do math? If so it won't hurt to check the original...If it is still within tolerance then you did not let out too much smoke.
Good point, i will check. I'm pretty sure it's done as the image does line up any more or at least didn't this morning.
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  #28  
Old 05-19-2018, 04:36 PM
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Quote:
Originally Posted by kevin kuehn View Post
can you please post up a picture of that new cap you had installed?
+1.
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  #29  
Old 05-19-2018, 06:35 PM
Wind157 Wind157 is offline
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Here it is
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  #30  
Old 05-19-2018, 07:24 PM
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Pretty sure the end that + is nearest is the positive end.

That cap looks like it was made in the 70's. As a general rule, you always want to use new or under 3-year-old electrolytics caps made in this mileneia are failing from age already that part looks like almost as much of a gamble as the originals.

I don't know how familiar you are with sourcing caps, but here is some advice anyway under most parts house web sites there will be passive components listed capacitors will be under them, Lytics will probably be listed as aluminum electrolytic, papers will be replaced by film types, other capacitor types can mostly be ignored. Most originals are of an outdated standard value selection the values 20, 30, 40, 50, 60 have been replaced with 22, 33, 47, 56 respectively (the industry transition happened from the 1940's-70's). So order a 56uF to replace the 60. The original lytic caps had a -50% +100% tolerance so there is tremendous fudge factor in choosing a replacement, but the closest modern standard value is recommended. Voltage rating: is the maximum voltage that can appear across the terminals before the lytic will fail and explode(or vent it's guts in a messy mineral oil steam)...You can select a new cap with a higher voltage rating (higher voltage cost money, and is bigger and less easy to fit so it pays not to go too wild) and the set may even be more rugged because of it, but never select a lover voltage (your new cap will die quickly if you do). When buying from one of the parts houses with a search engine with lots of options I first check the "stocked" box so I'm not waiting 6 months for the factory to make more. I also will select all voltages at or above what I need for a lytic, then capacitances close to the value, then sort by price and look at brands I have confidence in (Panasonic, Nichicon, Illinois Capacitor, etc.) and sometimes compare things like lead length, size and mounting in making the final choice. Honestly once you've got the correct value and a good brand you can't go wrong electrically (though good choices after can make mounting easier). On paper caps go with 630V for everything unless there is a higher voltage part in the set (get the correct voltage for that)...Going lower for some parts to save money/room is not worth the effort for paper/film replacemet.
Here are a couple of links to play with:https://www.mouser.com/Passive-Compo...ors/_/N-75hqt/
https://www.mouser.com/Passive-Compo...ors/_/N-9x371/

You can craft an order of the parts you need off of the schematic parts list. New film caps are rated in pF and the body markings are 2 value digits and a multiplier. So a cap marked 153k is 15000pF=.015uF In sams most caps with a voltage rating are paper, and most that start with a "." or are 1000 (pF) or more are paper, the first few are lytic and you can confirm by looking for polarity on the schematic.

The white tubular caps in some of your chassis pictures and the bumblebee paper caps (they look like giant black resistors with color stripes) are as much time bombs as the original lytics.

Damn, I dumped a lot of info on you. Sorry if any is old hat, TMI, or confusing. If you have any questions just ask.
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