- Joined: 28 Oct 2012
- Posts: 2
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SMS Repair Advice
 Posted: Sun Oct 28, 2012 7:08 am
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Hey everyone, this is my first post on the SMS Power forums but I've been using the site as a resource for quite some time now.
Anyway, I have a couple of issues with an SMS I recently picked up on the cheap and I was wondering if somebody could help me figure out how to go about resolving these problems.
The first glaring issue with the system is the video output. Everything on screen is tinted green and appears to be missing the red channel. I have only gotten to test this with the RF output on the SMS and not the A/V as I don't have a cable to test it with (my Genesis is a JVC X'eye and that just uses straight RCA).
I can at least live with bad colour for now, but the major problem is the first controller port seems to have some problems. In games (so far tested with the built in Hang-On as well as Shinobi, Y's and Wonder Boy 3 all giving the same result) the right direction on the d-pad always works, down works some of the time, left rarely works and up almost never works at all. Buttons 1 and 2 both work however, and I have tested this with two SMS pads and a Genesis controller all giving the same results.
Upon cracking open the system I do notice that the middle leg on EM 18 and EM28 are not soldered, and look like they never have been! Would this really be the root of the problem?
I have included 3 images, showing the board and video issues.
Thanks in advance for any help you guys can give me.
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- Joined: 24 Sep 2006
- Posts: 191
- Location: Sydney, Australia
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Posted: Wed Oct 31, 2012 1:09 pm
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Ignore the unsoldered pin on the EMI filters. It won't hurt anything.
To start with, I suggest you check the unit thoroughly for corrosion, especially the the controller ports and around the cartridge slot (people spill corrosive things in there).
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- Joined: 28 Oct 2012
- Posts: 2
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Posted: Thu Nov 01, 2012 5:18 am
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Thanks for the response!
Not seeing anything corroded as such, but the board isn't exactly clean. I'll break out the alcohol and give it clean to see if that helps anything.
In the meantime, any other suggestions?
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- Joined: 11 Dec 2009
- Posts: 204
- Location: Canada
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Posted: Thu Dec 20, 2012 8:21 pm
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When I converted my SMS console from PAL to NTSC I ran into some similar Video color issues. It ended up being a "cold solder joint" on a capacitor that was tied into the video circuits.
I located the cold solder joint using "SUPER COLD 134" aerosol spray. You could also just go and re-heat the solder points on components dealing with video. However, using super cold is the way to go, otherwise it's a needle in a hay stack.
Hook up your board and let it run, while the unit is running and shows the green image, try spraying a small blast of the Super Cold spray at different spots on the board and see if the video clears to show the proper colors. If it does, then that area you sprayed is the location of the cold solder joint and just go and re-solder all the solder points in that area. This should rectify the problem......if it is in fact a cold solder joint.
This could be a similar problem with your board, but again it's hard to say. You could give it a try. :)
-Gerry
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