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Main => Monitor/Video Forum => Topic started by: cky4987 on January 02, 2011, 01:21:22 pm

Title: Help identifying & diagnosing monitor issues.
Post by: cky4987 on January 02, 2011, 01:21:22 pm
Ok. Yesterday I bought a bad dudes vs. dragon ninja cabinet. It's in pretty good shape, but there are a couple problems with the monitor. It seems that the left side of the monitor is much dimmer than the right, and also when jumping in the game if you look to either side you can see a sort of white line that follows the character upwards and back down. I also am not sure exactly what kind of monitor it is. In the instruction manual for the game I found a seperate sheet containing a diagram for a monitor made by Matsushita, but on the back of the monitor there is a sticker that says it's made by Hantarex. Any help would be very appreciated.

(http://i165.photobucket.com/albums/u53/cky4987/2011-01-02_12-43-52_996.jpg)
(http://i165.photobucket.com/albums/u53/cky4987/908845171_photobucket_28446_.jpg)
(http://i165.photobucket.com/albums/u53/cky4987/908845171_photobucket_28445_.jpg)
(http://i165.photobucket.com/albums/u53/cky4987/908845171_photobucket_28444_.jpg)
(http://i165.photobucket.com/albums/u53/cky4987/908845171_photobucket_28443_.jpg)
(http://i165.photobucket.com/albums/u53/cky4987/908845171_photobucket_28441_.jpg)
Title: Re: Help identifying & diagnosing monitor issues.
Post by: lilshawn on January 02, 2011, 05:05:49 pm
sounds like all your issues can be solved with a cap kit.

those capacitors are probably starting to get old and drift out of specification. they don't charge up properly and therefore discharge to zero before they are supposed to. causes the screen to go dark on the side like what you got there, as well as about 100 other issues.

as for what it is, Wells Gardner 19'' 4900 series.... it's been replaced so the schematic you have there (unless it's some kind of mutant re-branded unit) is useless. a schematic can be had here: http://www.ahsco88.com/Monitor%20Schematics/Wells_Gardner_49xx_Repair_Manual.pdf (http://www.ahsco88.com/Monitor%20Schematics/Wells_Gardner_49xx_Repair_Manual.pdf)
Title: Re: Help identifying & diagnosing monitor issues.
Post by: cky4987 on January 02, 2011, 05:52:14 pm
alright cool. Thanks a lot man. As far as a cap kit goes. Any recommended places online to buy from? Or would I just be better off going to radioshack?
Title: Re: Help identifying & diagnosing monitor issues.
Post by: lilshawn on January 02, 2011, 07:31:44 pm
alright cool. Thanks a lot man. As far as a cap kit goes. Any recommended places online to buy from? Or would I just be better off going to radioshack?

aaaaaaak! don't even think about going to ratshack.

for what they would charge you for stuff there, you can get 10X the amount anywhere else. don't even bother asking about anything electronic related, unless your question has High def, cellphone, or satellite in it... they don't know what the hell you're saying. save yourself some frustration and avoid it. they even go so far as to profile you in that if they think you know nothing about what you are looking for, they will sell you the most expensive thing they have. they push worthless produ......
:soapbox:

you can get a CAPKIT online from a few places... between 10 and 20 dollars... google yourself up "4900 series capkit"  but if you have some electronics supplier in your area, you would be better to get a list together and get them there, that way you have them right away and you don't have to pay for shipping... just your time to drive there. onesies of the caps are all you are going to need, so there is no sense in buying 10 packs of each amirite? an electronics supplier will be able to supply single units for purchase. yellow pages or google up "electronic parts ______**insert name of your town/city here**" or maybe "electronic components"

Title: Re: Help identifying & diagnosing monitor issues.
Post by: cky4987 on January 08, 2011, 11:06:28 pm
Just wanted to update. I bought a cap kit, and installed it. It fixed all my problems, and the monitor now looks great. Thanks again.
Title: Re: Help identifying & diagnosing monitor issues.
Post by: Ken Layton on January 09, 2011, 12:18:32 am
The symptom you had is called "uneven brightness". It is definitely caused by bad electrolytic capacitors as you have now found out.
Title: Re: Help identifying & diagnosing monitor issues.
Post by: lilshawn on January 09, 2011, 05:21:24 pm
good job  :applaud:

be sure to check your B+ voltage, as often after the caps are replaced, the voltage can get out of whack due to service persons adjusting it over the years as the caps start to fail.
Title: Re: Help identifying & diagnosing monitor issues.
Post by: cky4987 on January 17, 2011, 05:08:15 pm
Although The picture is now mostly fixed, I still can't figure out how to make it completely fill the screen horizontally. I messed around with the horizontal width coil some, but honestly couldn't see any changes. You can see what I'm talking about in the 3rd picture I posted. I tried changing the horizontal position but, even when centered there's still empty space on both sides. Is this normal, or is it just this game????
Title: Re: Help identifying & diagnosing monitor issues.
Post by: lilshawn on January 17, 2011, 07:45:15 pm
A low B+ can cause width issues. Did you check it? Sometimes a small drop in voltage can cause the picture to squeeze in as the B+ is driven into the horizontal deflection yoke. Less voltage = less deflection. If the voltage is good, we can look other places. But start there.