Tektronix Scope Screen half black all of a sudden - Page 1
Forum section: electronics / repair

author: Fady
author_rank: Newbie
timestamp: May 19, 2016, 02:12:42 am
content: Hello everyone,The last time I used this scope (about 6 months ago) it was working. Today for no apparent reason the screen is half black (and the black part itself is half backlit and half totally dark)My initial guess is that it is not a screen issue since it is perfectly divided into two halves -- so its probably a driver issue.Any advice where to start with this?

author: tautech
author_rank: Super Contributor
timestamp: May 19, 2016, 02:20:38 am
content: Quote from: Fady on May 19, 2016, 02:12:42 amModel?GUI looks like a TDS1000 or 500 series.IIRC they use 2 backlight CCFL and 2 inverters.Identify the backlight inverter IC's and study the IC datasheet for atypical applicationthat may just match how Tek implemented the ICexactly.BTW. Use the flashlight trick on the dark part of the display to check if it's just the backlight missing....you should be able to make out the normal display if you look carefully.

author: Fady
author_rank: Newbie
timestamp: May 19, 2016, 02:46:50 am
content: Hi tautech,Model is TDS 1002..I don't believe the dark part has any picture on it. I am attempting to take it apart (seems to be another challenge) and proceed from there with your advice.Interestingly, I found a short youtube video showing a similar scope with the same issue, and the author doesn't seem to complain about it.

author: tautech
author_rank: Super Contributor
timestamp: May 19, 2016, 03:15:57 am
content: Quote from: Fady on May 19, 2016, 02:46:50 amDoesn't look the same to me.Yours is NOT side-shifted like the one in the vid.Got aTDS2000 here that I could like give you some measurements if needed. (display working)

author: Muttley Snickers
author_rank: Unknown
timestamp: May 19, 2016, 03:37:13 am
content: I have the same model here TDS-1002 not the B with the USB just the 1002 along with the TDS-2MEM module, compact flash serial and printer ports which I just noticed the battery date is 2004 on the module, not at all related just a note worth taking.I've never needed to take mine apart so cant really help you there but I'm pretty sure I have all of the manuals on the other computer, anyway Connor Wolf did a full teardown on the TDS-210 and the LCD connections may be similar on these.https://youtu.be/aBaMdVcKAWQ?t=1140

author: EPTech
author_rank: Regular Contributor
timestamp: May 19, 2016, 06:03:41 pm
content: Hi There,This is most likely a screen issue. Replacing the TFT will probably fix the problem. In early TFT screens you will often see several drivers, each controlling a certain half or quadrant of the screen depending on the screen panel size. It does not look like the back light is broken because you can still see the characteristic glow. As said before, it is probably a driver issue. You can try searching for driver IC's on ebay but if I were you, I would look for a replacement panel all together.Good luck!

author: nctnico
author_rank: Super Contributor
timestamp: May 19, 2016, 06:20:47 pm
content: I second the suggestion for a replacement panel. I have seen these kind of issues before with LCD screens and they are impossible to fix (properly) in most cases. In short: in these LCD screens data is shifted into shift registers which control the horizontal and vertical display lines. If the shift register breaks then the synchronisation is lost which results in a blank screen and/or shifted display information.

author: Lorenzo_1
author_rank: Regular Contributor
timestamp: May 20, 2016, 09:55:45 am
content: Had a similar problem with several Toshiba laptop backlit LCD screens which would break into 3 vertical slices, some blank, similar to yours. Problem there lay in the long and fragile strip connector at the base of the screen that broke down with repeated closing/opening of the lid. I could get the whole screen(s) back to life by careful finger pressure on the right part of the connector, but that only worked for a while and they eventually had to be replaced. A commonplace problem in some Toshiba laptops.