The numbers matched. I called the phone number on a Saturday morning and was done within five minutes. A technician from a reputable local company showed up at my door Monday morning, we took the TV off its stand and laid it face down on the floor, and he opened it up and began surgery.
He told me that the issue was a common one in flat panel TVs and was actually keeping him in business. Samsung has said that the problem affected "approximately one percent of Samsung televisions sold in the US from to Update: a reader tells me that my blown 25V capacitors must have done some other job instead, as they aren't powerful enough to zap a backlight, which needs ridiculously high voltages to start and which is usually powered by a transformer. When we tested it, the TV lit on its first click.
Samsung has denied the claims in the Oklahoma City lawsuit, but to its credit it did agree to take care of the problem and did so even before the settlement was reached. And, at least in my case, it did so in an absolutely painless way. My technician walked out the door without me paying a cent. The experience was positive enough that the dark thoughts I had been harboring—"I am never buying a Samsung product ever again!
While it's working fine again now, I keep wondering how long I have until the next design flaw blows out some tiny component. The phone number to do so is You must login or create an account to comment. Skip to main content Samsung TV internals—note the bulging tops a sign of failure on four of the black and silver capacitors. Daniel Parks. Part of my receipt, showing the nine 25V capacitors used to replace the bad ones. I recently started to look at the power supply circuits of many of my expensive electronics that were on the fritz and for me, most of them were indeed bad caps.
It's amazing what a little DIY know-how can do. For what it's worth, a few years ago , maybe? The caps would go bad in short time, often within years. Some companies managed to track the issue back to the source and purge their supply stock but I'm betting not every company did and it wouldn't surprise me to see that these bad caps were recirculated on the supply side as a great deal so even more recently manufactured items could be affected.
It certainly seems that Samsung might be affected by such an issue, with so many caps going bad at once. Rather than replacing the whole TV, it is sometimes possible to simply replace a damaged capacitor.
Capacitors are checked using a capacitance meter. Turn the TV off and unplug the power cord from the socket. Because capacitors are designed to hold their charge, wait for ten minutes before proceeding to ensure any charge has been drained.
Use the screwdriver to remove the back section of the TV. Keep all the screws in a container nearby to make reassembly easier. Turn the capacitance meter on. Use a small plastic bag to hold the chassis mounting screws, knobs, and any other parts.
Turn the chassis on its side or back so that it will lie still while you work. Be careful not to damage delicate parts when you turn it over. Don't rest the radio upside down on its tubes. If necessary, you can prop up one side of the chassis with a book, small block of wood, etc. My Midwest DD article describes a simple holder for large and heavy chassis. Some purists go so far as to hide new capacitors inside the shells of the small non-electrolytic paper capacitors.
This preserves the original appearance, but it is rather tedious. I have done this only in a few cases, for my most valuable radios. If you are interested in doing this, read the restoration articles for my Sparton Bluebird or Colonial Globe.
Using your wire cutters, snip the leads of the old capacitor about one-half inch from the terminals where they are connected.
Leaving a little "tail" on the snipped wire makes it easier to remove. Set the old capacitor aside. Use your soldering iron to melt the solder on the terminal, suck the excess solder from the terminal, and use your thin pliers to remove the snipped wire tail from the terminal.
You may need to unbend the tail a bit to work it free. If it is very firmly crimped onto the terminal, try snipping the bent portion to free it in two pieces.
Sometimes, a thin implement such as a nut pick or dental pick is handy for nudging the snipped tail out of its lair. A round wooden toothpick may help to clean out little circular holes in a terminals, since melted solder doesn't stick to wood. If the snipped tail is attached to a pin of a tube socket, avoid using too much force to pull it loose.
You might yank the pin right out of the socket or even tear it in two. The same goes for other components that are attached to the same terminal. Old carbon resistors are brittle and will break if handled too roughly. Once in a while, a capacitor will be mounted in cramped quarters, so that you need to unsolder another lead or component to gain access.
In such a case, make a note or draw a picture so that you can reconnect everything correctly. After you remove the snipped tail from the terminal, look carefully to make sure that you didn't leave any bits of wire or solder crumbs in the chassis.
Small bits of metal can cause problems if they lodge in between two connections and make a short circuit. Hint: if you do a great job of cleaning the old terminals, it may not be obvious to the eye where the new leads should go. If you are interrupted at this stage in the process, loosely stick the leads of the new capacitor into the terminals so that you won't be scratching your head with puzzlement when you return.
It's easy to forget exactly where things went, after an hour or two. You can also temporarily attach the ends of clip lead to the connection points as a reminder.
It is good practice to test every new capacitor before installing it in the radio. Modern capacitors are generally high quality, but every now and then a bad one slips through. If you don't have a capacitor checker, you can at least test the capacitor's resistance using a multimeter.
The ohmmeter should show infinite resistance on all scales. Any continuity is a sign of leakage and a leaky capacitor must be replaced. New capacitors usually have wire leads somewhat longer than needed. Your first job is to trim these leads and bend them to fit the spot. Hold the new capacitor near the place where it is to go, bend the leads to fit, and then trim the excess wire from the end of each lead with the wire cutters. Leave enough length on the lead to allow for crimping it around the terminal.
Again, be sure to avoid leaving stray bits of wire inside the chassis. If the terminal is the type with a hole, slip the end of each lead into the hole. If you did not clean all the old solder from the terminal, you may need to heat the terminal to soften the solder before slipping in the lead.
After the lead is through the terminal, carefully bend it around the terminal. Before soldering the new capacitor in place, you want to make sure that it has a solid metal-to-metal connection with its terminal! When both leads are securely crimped onto the terminals, heat each joint with the soldering iron and apply new solder. Apply solder to the joint , not to your soldering iron. If the solder doesn't melt when touching the joint, then the joint is not yet hot enough. Don't jiggle the connection while the solder is cooling.
That can create a "cold" joint that is not reliable. Sometimes, when a delicate component is connected to a terminal, I'll temporarily clip a metal tweezer onto that component's lead, to act as a heat sink and prevent overheating damage.
After replacing the capacitor, doublecheck your work against the schematic to make sure that you connected the right component to the right places. If the radio or TV is in working order, I often turn it on for a quick test after replacing each capacitor. Even professionals make absent-minded mistakes from time to time, and this brief road test will reassure you that you haven't made things worse!
If your set doesn't work at all, you will obviously need to do some other diagnosis and remedy the problem before turning it on. The "test after each replacement" routine applies only to radios and TVs that are basically working in the first place. Obviously, if you are testing the radio with the chassis exposed on your workbench, use extreme caution to avoid getting a shock.
Temporarily put the knobs back on their shafts before turning it on. Don't touch anything except the knobs while the radio is plugged in. Unplug the radio before resuming your recapping. That's all it takes!
If you can replace one capacitor, you can replace 'em all, so go to it. Replace the remaining paper or molded paper capacitors one by one until you reach the end of your list. It's good practice to make a note of each replacement as you go along, to prevent confusion and to make sure that you haven't skipped anything.
I usually check off each part on the schematic and parts list:. Digital photos are extremely useful, and since they're virtually free, why not take a lot of them? I take detailed photos of every radio or TV chassis's underside before starting work. If confusion arises later, those photos will show you how things were connected before you started messing around. I take more photos from time to time as my work proceeds, whenever I want to record something important. Starting in the s, manufacturers introduced printed circuit boards.
Instead of wiring every component separately, the wiring was pre-applied to a board and the component leads were soldered into little holes in the board. Replacing caps on PC boards is usually not difficult, but you'll need to use slightly different techniques. The mechanics of disconnecting the old capacitor and soldering in the new one are the same for electrolytic capacitors, so refer to the previous section for those basics. Electrolytics are special in a couple of ways, however.
First, their large capacitance value means that they can store an electrical charge—enough to deliver a painful shock—even when the radio is turned off and unplugged. Before touching the leads of an electrolytic capacitor, discharge the cap by shorting its leads together with an insulated clip lead.
Secondly, their large size introduces some complications in installing the replacements, which we discuss in the following sections. Most electrolytics contain metal foil and a paste, which dries out over time and causes failure. In s or earlier radios, you may find a "wet" electrolytic, which contained a weak solution of boric acid rather than paste.
You can read about wet electrolytics in my Philco 60B restoration article. The simplest option is to disconnect the old can and leave it in place for appearance's sake, then wire the new capacitors out of sight underneath the chassis. The radio looks original from above and you will save a lot of time and effort. This method was used in the Grundig radio shown at the beginning of this article. The big blue components are new capacitors installed under the chassis.
The second option is to "restuff" the can. You remove the old can, pull out its innards, hide new capacitors inside, and reinstall it. This takes more work and I do it only for special or valuable sets, or in the rare case where there's no room for a new capacitor under the chassis.
There are various types of can electrolytics, so the procedure used to restuff will differ, accordingly. The previously listed articles show cans that are completely removed, stuffed, and then replaced like before. An alternative is to cut the can above the chassis, install the new cap leads through the old base, and then put the emptied can back on. The first thing to remember about installing electrolytics is that polarity matters! You must install them with the positive and negative leads in the right places.
If you reverse the leads, the capacitor may overheat and explode. Needless to say, your radio will not work, either. New electrolytics are always marked to indicate which end is positive and which is negative. Most often, a band of arrows and minus signs is printed along the length of the capacitor. The arrows point to the negative - end.
In the following photo, the negative ends of the larger capacitors are all to the right. If you don't hide the new caps inside the original can, you must decide how to mount them under the chassis.
Many sets have enough "elbow room" underneath to fit in a couple of additional components. Some battery portables, however, pack components tightly into a small chassis and may have little if any spare room. The important factors are to mount the new capacitors securely and to insulate all connections. Multi-section cardboard capacitors are often mounted on the chassis with a metal clamp. In the next photo, the clamp has been removed from the top unit.
If the clamp is attached with a screw, you might be able to reuse it as a mounting point for your new capacitors. When the clamp is riveted on, I usually cut through the band with a Dremel Moto-Tool and cutting wheel don't forget the safety glasses!
As mentioned earlier, some times the metal can itself comprises the ground connection for a vertically-mounted unit see following photo. If you replace such a can with a compatible metal-cased unit, you will need to make sure that the new can is well grounded to the chassis.
The can of a vertical-mount unit does not always provide the ground connection, however. In the following photograph, the middle unit in the bottom row has a can that is electrically isolated from the chassis. The common ground connection is made through a terminal or wire coming out of the can's bottom. Note : The "ground" connection point in a radio is not always the chassis. In many radios with transformer-type power supplies, the chassis acts as the common ground point.
When you replace electrolytic capacitors, take care to connect the negative lead of each new capacitor to precisely the same location or terminal at which the negative lead from the old part was connected in the chassis.
When you wire up the new capacitors, keep the leads as short as practical. Depending on the layout under the chassis, some times it will work better to remove the old capacitor leads completely and solder the new leads directly to the appropriate terminals. In other cases, where the old leads were quite long but still in good condition, it is acceptable to solder the new capacitor leads to the old leads. You can insulate the new connection with a short piece of plastic heat-shrink tubing.
If the underside of the chassis is cramped, you may need to mount the new capacitors somewhat distant from the original location. Look carefully at your schematic and at how things are connected under the chassis. As long as your capacitor connects to the right points in the circuit, its physical location might not be too critical.
For example, if the common negative point is the chassis itself, there may be a closer ground connection available, making for a neater chassis layout when you are done. As a rule, position your new electrolytics as close as possible to the original connection points. If you relocate a power-supply capacitor, don't place it next to RF tuning circuits or high-frequency circuits, where it may create RF interference and cause buzzing or other misbehavior.
Avoid locating the new capacitor in a place that blocks access to other components. Some day in the future, you or someone else might need to make more repairs, so don't make that job more difficult.
Sometimes, you can use a plastic tie to hold the new capacitor in place. For instance, you could tie the body of the capacitor around a nearby bundle of wires. Don't use a plastic tie to go around uninsulated leads or any component that gets hot. If the leads of the new capacitor are short enough, they alone may hold the capacitor in place.
I have also used metal clamps or even a dab of epoxy glue to secure new capacitors. Don't use hot glue for this purpose; the heat of the radio may soften the glue and allow the capacitor to fall loose. No matter how you install the new capacitors, use spaghetti tubing or other insulation as needed, to prevent short circuits. The hot ends of these capacitors carry comparitively high voltage; you will be sorry if one of them slips loose and fries other parts.
While you are replacing electrolytics, it is also an excellent time to replace the power and cord and install a fuse on the power line if your radio does not have one. A fuse is an important safety feature which many old radios lack.
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