It used to be you could crack open a TV or radio and really work on the components inside. The smallest thing in there was maybe a disc capacitor a little smaller than your pinky’s nail. Nowadays, consumer electronic boards are full of tiny SMD components. Luckily [StezStix Fix?] has a microscope and the other tools you need. Someone sent him an Amazon Echo Show with a bad touchscreen. Can it be fixed?
The video below shows that it can, but there’s a twist. The bad capacitor was mounted on one of those flexible PCB cables that are so hard to work with. It is hard enough not to damage these when you aren’t trying to remove and replace a component from the surface of the cable.
[StezStix] didn’t have schematics, so he had to use the “Columbus method” (you know, hunt until you find it), but that worked in this case. Turns out a burned finger broke the case. We liked that he showed his hot air mess-ups, where he blew a handful of components off the board. You may, however, want to hover over the mute button for the fast-forward dance party music.
We envy [StezStix] the feeling you get when a repair like this works. SMD fixes can be rewarding. We’ll remind you of the utility of covering parts you don’t want to heat with hot air using tape.
Thanks [Jim] for the tip!
There’s no law that prohibits people from using CRT TV. To receive digital TV you can buy special converters on AliExpress. In fact CRTs are better because they have full viewing angles and better color reproduction than LCD displays. Their only downside is slightly higher power consumption – but you can fight it if you develop a healthy ritual of shutting off TV when you walk out of the room.
OK, gramps. You realize that flat-panel display tech has moved significantly beyond this caricature you have in your head of “LCD displays”, right? No, apparently you don’t.
You’re right. Now, they can spy on everything you say and on your viewing habits, too. You gotta love the arrogant modern generation who thinks that everything that is new is better just because it’s new and that anyone who disagrees is just some “boomer gramps” who is obviously wrong. 🙄
You do realise that “Peter Puffer” is a troll. I expect he’s the same troll that we had previously, who has gone a bit quiet lately.
I still have a CRT TV in my shop and you are correct. The image is better than then overly sharp image from my LCD TVs. When I first got one of the LCDs, the edges of everything were SO crisp and sharp that it looked completely unnatural. Over the years, I’ve gotten used to it, but…
there’s no indication that there was a law
I ditched CRT computer monitors in 2000, didn’t get an HD TV until they stopped broadcasting football in 4:3 (my wife complained)
Show me a 75″ CRT TV that is capable of displaying 4k video and doesn’t weight as much as a car. Some of the last CRTs were just touching 1080
Back in the day my best Digital tuner was a DirecTV Samsung unit that pulled the digital channels even with no Dish connection. Even had component and DVI outputs. Some nice equipment from late 90s/early 2000s.
I have an old dashcam that has a broken (ground) trace on its flex cable.
Someday (sigh!) I’ll solder a jumper wire between the 2 PCBs.
A hot air gun is the wrong tool for such a task – note the difficulty in not blowing other parts off the flex.
A plain old (temperature regulated) soldering is the weapon of choice for removing and replacing such simple components.
It takes seconds and isn’t difficult at all.
It should be easier to repair components on a flex cable. The material has a much higher temperature resistance. A normal FR4 PCB will melt long before a flex cable will. Of course, if you’re melting your PCBs you are probably doing something wrong to begin with. But it might be easier for beginners.
huh thanks for this because my initial thought was that you’re wrong but now i realize i might just be totally ignorant about flex cables.
my impression is that flex cables melt really easily but i just realized, i got that impression from trying to solder on the flex cable that represents the connector edge of a keyboard membrane. i never realized it before, but i guess you’re saying that real flex cables are made out of something more like kapton than the low-temperature plastic i ran into in that scenario? i will be more willing to experiment next time i run into a flex cable repair. thanks
It’s been a few years since I had to deal with flex cables at a former workplace, but I don’t recall having much success soldering on those cables. Maybe the company was using cheap flex.
Should I tell my horror stories of the days when I hand soldered fine pitch 80 pin connectors to ribbon cables because no fab house could ever do it?
They were temperature sensitive as hell and the glue would bubble outside of a strict temperature range. Then you would get solder bridges, and you would hope to hell that they were on the first row. I developed tools and procedures to correct solder bridges on the second row and worked by microscope, but it was absolute torture.
10 minutes spend breaking and then fixing back Radio portion of the device for no reason
breaking component on a flex with brute force
resoldering said component back and ripping actually shorted cap off
He got there at the end so all good :) but all the drama was self inflicted, diagnosis took 10 seconds with thermal cam @19:33