That’s right, two Techie Talks in a row! Things were pretty crazy here over the past 3 months as Christy and I both moved to new places. I moved in April and she moved in May. The awesome thing about that is besides to being much, much closer to her, she found a TV on the side of the road that someone was throwing away! So we went and grabbed it not knowing if the TV worked or not. Also this thing is huge! In my head when she was telling me about it, I was imagining at max a 40″ LCD TV. NOPE! She had just found a 50″ Plasma TV complete with remote and power cord! So we successfully shoved it in her car and transported it to my apartment for easier possible troubleshooting and later moving to her place (She was due to move in a couple of days). After barely getting it up the flight of stairs (We tried to weigh it but scales are stupid. My guess is it is probably 150lbs) we plugged it in to see what was wrong with it and…
Well, sort of worked. The TV had full picture and sound, but the picture would start to sparkle and then disappear after about 20-30 minutes so apart it came!! At least some older TV’s were made with the thought that they could be easily taken apart just in case it needed repair! I think there were at least 30 screws for the back panel! Upon probing the voltage test points, one of the voltages would drop from 280ish volts down to 80v when the TV was on for thirty minutes and then the picture would disappear. When I was looking at the power supply in the TV, one of the capacitors looked like it was starting to bulge. So I thought it might need new caps as I have replaced those on one of my own monitors and an LCD TV that one of my friends also found waiting to be thrown out.
So i set off removing the power board to measure and write down the capacitor voltages and farad values to eventually order (I didn’t have internet for the whole first month that I moved… I don’t know how I didn’t go crazy! What’s that oven? The cookies are done? Huzzah! You make such delicious treats! Oh hey, microwave! Remind me to buy a couple of light globes on the way home from working at the place of many flashing pictures! It’s too much not see in here!) Ahem. Sorry ’bout that! Once I had gotten internet, I then ordered replacements for all 40+ caps that are on that board. So I waited, they arrived, I removed and then replaced. I then slapped that sucker back in the TV, grabbed a fire extinguisher just in case (Capacitors can explode if installed backwards so I was taking many precautions), plugged in the TV to a power strip using an extension cord so I would not be directly behind the TV when plugging it in, and flipped on the power to the strip.
No fire. So far so good. Red light came on, all is normal. Pressed power button. Still no fire, green light came on. Also good. I had picture and sound on the TV! YAY! I didn’t make it worse! Now to wait and see if the picture stays!
Nope. The picture still disappeared after 30 minutes. So after some more thought, I decided to point a USB fan that I got for mining at each heat sink in turn to see if something was overheating. First two heat sinks, same problem. Third heat sink, the TV stayed on past 30 minutes! In fact, it stayed on for 5 hours until I had to turn it off due to going to work! Upon returning from work, I tested it for an hour and then turned off the fan and it lost picture again after 30 minutes! I then turned the fan back on and after letting it cool down, powered it back up and left it running overnight constantly playing videos to try to stress it. It was still going after 12 hours!
So I went to Best Buy to pick up a pair of computer case fans to install in the TV and then started designing things to hold the fan to the heat sink as the fins were way to big to screw into.
Many revisions were printed by Robot 1 (see above) but I had finally gotten them to work!
I also added another connector just in case I needed to put in another fan at a future point for the other heat sinks. (It’s the white connector near the bottom of the first picture of the gallery) The added benefit of using the TV’s fan power rail? It turns on and off with the TV! Huzzah! One TV that was saved from the trash heap by my wonderful Robot 1!