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News announcements and other topics => News => Topic started by: tinman on May 05, 2014, 06:47:56 AM

Title: SG screen problem>??
Post by: tinman on May 05, 2014, 06:47:56 AM
Ok,as some of you will know,i bought a new Atten SG(along with a scope and power supply) less than a year ago.Last time i used it(a couple of months ago),all was fine.Tonight i went to do some testing with pulsing an LED at high frequencies,and the pic bellow shows what i see on my screen now. So last time used-was all fine--two months later-it's RS.It is housed in a clean dry enviroment(the lab),along with all my other stuff.
So what has gone wrong here?.
Any help would be much appreciated.
Title: Re: SG screen problem>??
Post by: MarkE on May 05, 2014, 06:59:43 AM
Quote from: tinman on May 05, 2014, 06:47:56 AM
Ok,as some of you will know,i bought a new Atten SG(along with a scope and power supply) less than a year ago.Last time i used it(a couple of months ago),all was fine.Tonight i went to do some testing with pulsing an LED at high frequencies,and the pic bellow shows what i see on my screen now. So last time used-was all fine--two months later-it's RS.It is housed in a clean dry enviroment(the lab),along with all my other stuff.
So what has gone wrong here?.
Any help would be much appreciated.
I would suspect:  1) The flat cable connection for the LCD on the main board has gotten loose, or 2) The LCD display has gone bye bye, or 3) The LCD controller probably located on the main board has gone bye bye, or 4) The unit is suffering from the plague of bad electrolytic capacitors.
Title: Re: SG screen problem>??
Post by: tinman on May 05, 2014, 07:03:32 AM
Quote from: MarkE on May 05, 2014, 06:59:43 AM
I would suspect:  1) The flat cable connection for the LCD on the main board has gotten loose, or 2) The LCD display has gone bye bye, or 3) The LCD controller probably located on the main board has gone bye bye, or 4) The unit is suffering from the plague of bad electrolytic capacitors.
I dont know MarkE. It is only 6-7 months old,and wouldnt have done 10 hours. All was good last time i used it,and now after sitting for a couple of months,she's no good.
Title: Re: SG screen problem>??
Post by: mscoffman on May 05, 2014, 09:37:34 AM
Sometimes an instrument manufacture does not get to the latest LCD display technology. The square format of this display says that this might be the case here.
I think this indicates that either some grounding problem is occuring or some virtual grounding problem is occuring where the LCD display generates it's contrast
signal.  If there is any way to get the instrument apart to get access some of the LCD points I believe this would be solvable. I don't have much experience with
this because portable computer LCD displays usually are not accessible much at all nowdays. Sometimes on the web, someone will go through and actually
teardown various instruments to the component level this may be true of Aten series. One thing you should look for is water damage. Instruments need
to be kept in a non-condensing humidity environment though I realize that this is not always possible. By probing cleaning and checking especially flat no header
cable connections I think this is solvable. If the problem changes when mechanically manipulated, it is probably not inside an IC. Even if it is inside an IC
sometimes by careful adding an external bias resistor you can get things functioning again. I hate it when this happens, when it happens multiple times
I tend to stay away from that brand as they may be committed to using too cheap LCD's displays or not thoroughly removing solder flux.

:S:MarkSCoffman
Title: Re: SG screen problem>??
Post by: Vortex1 on May 05, 2014, 10:51:55 AM
If you were exploding any HHO gas or discharged a large HV capacitor into a low inductance coil in the area it is possible the EMP took out a sensitive mosfet chip. Even playing with a Tesla Coil near equipment can build up destructive charge that can take out a mosfet part.

I have seen equipment failure from EMP on my bench. I don't do that kind of stuff near my good equipment anymore, having lost an unconnected Fluke DMM and a HP scope.

A screened room or box is a good idea if you intend to play with the HHO stuff or other impulse discharges near sensitive equipment.

Of course, the other suggestions are also very valid.
Title: Re: SG screen problem>??
Post by: magpwr on May 05, 2014, 11:44:53 AM
Quote from: tinman on May 05, 2014, 06:47:56 AM
Ok,as some of you will know,i bought a new Atten SG(along with a scope and power supply) less than a year ago.Last time i used it(a couple of months ago),all was fine.Tonight i went to do some testing with pulsing an LED at high frequencies,and the pic bellow shows what i see on my screen now. So last time used-was all fine--two months later-it's RS.It is housed in a clean dry enviroment(the lab),along with all my other stuff.
So what has gone wrong here?.
Any help would be much appreciated.

hi tinman,

You may want to try your luck by touching the display at various corners to see if there is any improvement in display to discover if there is any possible loose connection to display panel.
That's the only solution i have from my end,can't promise anything.Good luck.
Title: Re: SG screen problem>??
Post by: Marsing on May 05, 2014, 11:57:26 AM

Perhaps the lab where you keep lcd don't have constant temperature that caused steam/dew/water inside lcd. so, check all connection, blow with "hot air blower" at necessary point carefully, maybe  will solve the problem.

Good luck, too. 
Title: Re: SG screen problem>??
Post by: e2matrix on May 05, 2014, 10:29:15 PM
Yes if it's not under warranty pull it apart and disconnect any and all connectors one by one and reseat them.   If it has any chips that are in sockets carefully pull them and reseat also (but I doubt there will be on this unit).   Use anti-static wrist strap or similar when doing any of the above.   Look for any blown caps or other obvious fried parts.   I fixed one 400 MHz digital scope that was only suffering a blown cap.   
I'd write the manufacturer also to see what suggestions they might have (if not under warranty).