My Samsung LCD broke. I took it apart, wiggled some cables, but it didn’t help. The symptoms are that the whole picture is just vertical bands. No input method works, even the built-in menu doesn’t show. It’s all vertical stripes in various colors. (Audio works.)
I think i’ve figured out what’s wrong. I have a hunch that the TV is all analog internally, except for the LCD panel, which is driven by an ADC. I think it is that ADC that is busted, and it sits on its own separate PCB. I think if I can just buy this PCB, I can swap it and fix everything. However, where the hell do I buy it?
P.S. I used the TV mostly as a VGA monitor. The TV broke a few days after I bought a KVM switch. The night it broke I unplugged it and left it alone. In the morning it worked perfectly, for 10 minutes.
TV sets are rapidly becoming all or mostly digital. Call the manufacturer’s regional or national service center to inquire about the availability of service manuals and parts. They may tell you that you have to ship it to an authorized service center for repair. Many TVs and monitors are not repairable. If under warranty, they just send you a replacement.
I don’t think this is a valid assumption. I recently pulled open a large Samsung LCD TV (dead panel according to the 3rd party non-warranty engineers - dead PSU according to my 'scope) and the main video board is basically a video card.
Given the propensity for LCD TVs to include (and require) extensive signal processing, I think it’s sensible to assume that any non-digital signal is digitised quite early on.
In answer to your main point, have you tried googling for the pcb codes? I found pretty much all were available, just not very cheaply.
From the description of your fault though, I think it’s likely to be the panel controller (sync with the video stream, clocking the data in, rinse & repeat) or the panel itself in terms of row/column controlling or data clocking - depending on the tech.
Have you got a 'scope available? You can get a general feel for the signal just by looking at it. Which is why I love digital electronics
I had the feeling it was all-analog because when I unplugged the cable feeding into the smaller pcb, the colors changed like when messing with a VGA plug. So I think it was all analog leading up to this smaller PCB, the fault was in the ADC there, and that’s why everything, including the on-screen menu, was corrupted. (Plus, when I tried hooking up my PC to the TV using HDMI, the results were absolutely horrible, much worse than using VGA.)
I tried calling Samsung and specifically asked about buying my own parts, but they said no. Maybe the person didn’t know? But I got the feeling they didn’t care about me except to refer me to someone who’s gonna rip me off. The TV is nine months out of warranty. I have a feeling if I call the repair guys, they’re not gonna care either except to do it by the book. Maybe I could bribe them?
That’s interesting. No. Should I look for a number on the PCB and just search for it?
I do, actually. A great 400MHz dual-channel. However, I don’t think it’ll help me.
I recently had my rear projection HDTV blow its projector bulb (within the warranty period). I was fortunate to have a technician who came out to replace the bulb answer several questions concerning HD TVs, including rear projection, LDC and plasma.
His response across the board with replacing parts was to forget it and but a new TV. Unless the TV is under warranty, several critical components to HD TVs cost more as replacement parts than buying a new TV.
Holy crap. It took me forever to find, but Samsung actually has a website, samsungparts.com, where it lets you buy all this crap, plus service manual! I don’t think any other manufacturer does this. The prices are a bit high, but it’s all there. No seedy websites or underground communities!
Finally I’m about to order the replacement LCD driver (which, through lengthy searching, especially on ifixit.com, i’m pretty sure is the cause of my problems. this isn’t the A/D converter, but it is the original small pcb that I was looking for from the start).
Biggest thing is I had to know Samsung’s part # for the part. When searching by the panel manufacturer’s # that’s silkscreened on the PCB I did not get very far. The real # I got from samsungparts.com, but the service manual would have it too.
