4/17/2016

Interesting little crystal tester I got from ebay

I saw a video by Joernone where he shows a crystal tester he built. I thought that would be pretty cool to have but I did not have some of the components to build one. While looking to order them I found a completed board that does all the same things plus a go/no go light for a pretty reasonable price.
http://www.ebay.com/itm/Electro-Resales-Crystal-Tester-and-RF-Generator-XTRF-/152053865120?

I bought the board, made some minor modifications to it, and mounted it in a project box.
Here are the results:

I went through all the crystals I had, I only found one dead one, a couple that oscillated strangely, and almost all of the crystals were spot on (or very close to) their rated frequencies.

4/10/2016

ViewSonic VA2431 LCD Monitor problems

I received this monitor from my work several years ago and it was working perfectly up until a couple of weeks ago.

My monitors are calibrated, and when I do certain things like:
login through remote desktop and then login from the console or
play minecraft and exit the monitor loses it's settings and I run a special program to restore the settings.

Lately my monitor had a pink cast to it that would not go away when I ran the program to restore the calibration. I thought maybe it had lost it's calibration so I did a fresh calibration and that seemed to fix it... for about  20 minutes, then it went pink again. I did another calibration and it seemed to work but after 5 minutes it started flashing between pink and calibrated.

sigh™

I opened it up and it did not appear to have bad electrolytic capacitors but I replaced them anyways. I tested the old caps and all of them were leaky including the large 450v filter cap.

Now it works fine.