Monday, March 29, 2010

Computer Fixin's Part Deux, the Finale

Today the screen came in. It was simple to install, with the hardest part being to remember where the screws go. Because of this I tried turning it on before adding the hardware, as can be seen below.
After I got it all put together it was fine. Hooray!

For the record, I bought the screen on Ebay. The supplier was in China, and the screen came from Shenzen, China via UPS. Total time on this project was about 1 hour.

Sunday, March 14, 2010

Computer Fixin's Part Deux, Laptop Fixin's

My sister bought a Laptop recently, it is a Gateway NV7802U. Not a bad machine, it has a 2.2GHz processor, 4 GB Ram, and a 500GB. Tiger Direct review. Last week, I was told there was a problem and I said I would take a look. Below, it is in its natural state.Unfortunately, when it is powered up, it is obvious what the problem is. She stepped on it and broke the screen. I found a replacement screen for the Laptop model on ebay for $149.99 but I thought if I might open it up I could find the model of the screen. The idea was, I might find the screen directly for less money somewhere.
After some fairly difficult figuring out, I was able to pull the screen out. It was a little funny as there is a webcam in the cover just above the screen. There was also two screws in the bottom of the laptop that had to come out.

After taking it out, I turned the screen over to find the model. Voila! Here it is, a Samsung LTN173kT01-A01. You may notice that the screen (and the laptop, for that matter) was very recently made. "0935" is a date-code meaning 2009, week 35. This puts it late August of 2009.
Unfortunately, my plan hit a wall when I could only find this type of screen for more than $149.99. It turns out that the replacement for the Gateway that I found on Ebay is not this model, but instead an LG LP173WD1-TLA1 and the LG is cheaper. It looks like the LG would fit, but I am currently doing research to conform. I can imagine that Gateway manufactured this laptop (and the rest during this run) with whatever parts they could get at the moment and this screen happened to be a Samsung. At other times, they might use the LG.

Stay tuned to see if I can fix it.


Monday, March 8, 2010

Ground Loops

Last week at work, we proved that ground loops with an oscilloscope can be a bad thing. Here is a description of what happened, but the pictures mostly speak for themselves. As I understand it (I was not present) the issue occurred when a setup involving 277 volts was present. Our oscilloscope was not plugged into earth ground through the third prong, which was supposed to help look at AC signals. Unfortunately, the 'scope was plugged into the PC via the serial port (to wave capture) and then the serial ground provided at path for potential disaster. Basically, all the grounds in the circuit should be at the same point (voltage), ours were not.This picture is from the serial port on the back of the 'scope. Notice anything odd?
Same board, different angle. In this picture you can almost see the lifted traces on the board as well. That trace goes from one of the pins on the DB9 to the chip. The yellow cap. next to the chip isn't looking great either.
As it turns out, since the loop was through the PC, it was not spared either. Shockingly similar failure to the 'scope. Lucky for all of us, the hard drive was spared any damage and a duplicate PC was located to replace this lost one. The 'scope, however, could not be replaced as easily.

Thursday, March 4, 2010

Give him the Clamps!

Last September, me and Freshman were in the Barre/Montpelier area to pick up some fireworks, and we stopped at R+L Archery to check out some more fun things. When there, I saw cray fish on sale for $0.50 each (as fish bait.) So what could I do? I picked up a few and I named them all clamps. Long story short, I have one left.

Notice the food to the right, and the electrical box in the back. He calls that home. Sometimes I don't see him for days while he is hiding. The point of this post is a new development. Recently, clamps molted, why not, and when he did, he came out with one less claw. Actually, he came out with the whole arm missing. The question is, will it come back?