Sega Saturn PAL VA9 ( Problem Picture Shaking Wobble.. Help

[zyrobs]

Replace all the capacitors on the motherboard (make sure you use the lowest profile caps you can, otherwise they won't fit under the EM shield) and replace the EMI filters on the a/v output (the row of black little boxes in the back, according to my notes the correct replacement part should be the Murata DSS6NC52A101Q55B).

The last time I did this, it was on a console that wobbled heavily and also crashed a lot. After replacing all the caps and just the filters on the a/v output, the console became rock stable, the screen wobbled much less, and the colours became stronger to boot. However I don't know if it was the EMI filters or the caps that made the difference as far as the video output is concerned (recapping is definitely what fixed the unit crashing). Still, I know that both the caps and the filters are failing, so it is probably safer to replace both.

The caps might not look bad, but they are more than 20 years old now. They are past their life expectancy and do not perform as well as they have to, hence why the wobbling image and random crashing is more and more frequent of a problem. Replacing the power supply caps is not necessary (the issue is caused entirely on the motherboard, I tested this), but you might as well do it to be on the safe side.

And again, make sure you get low height caps for the motherboard, or else they will not fit! Even bent sideways, they might be pushed by the drive holder pegs of the EM shield, which crushes them.

[Sega Fanatic]

thank you friend for the 
information, you are right must be more problems because the capacitors are failing i dont  no if i can replace all alot work for me


i have other question if you can help me  on doing the 50hz / 60hz mod switch on pal sega saturn i have first model 2 with jumpers on back cover

the switch must be spdt right 3 legs and 2 position ?  most say  Maximum current at 250V AC = 3A or need to be 5A ?  can be ON/ON or need to be ON/OFF switch ?

also i found this mini switchs so this will work too ?  because only say  Rating: 0.5A 50V DC and others on ebay say even less = 0.3A  

thanks alot you the man

[zyrobs]

The SW4 switch doesn't need to be high amperage or voltage since it's just a DC jumper pin really. A simple on/off switch will do fine because the three grouped pins have pullup (or was it pulldown) resistors under them.

I haven't found any switches that fit both physically and electrically, the few that fit physically, did not match the pin connections.

However you can use a OS102011MS2QN1 (upright) or a OS102011MA1QN1 (angled) if you cut off and file down one of the grounding pegs on the side - then it will fit in the three side pins and the left grounding peg perfectly. Took me some time to find them. Because they physically fit the pin locations, these switches make the best connection, without needing to dick around with making extra cables and such. And they are small enough to fit under MPEG cards (even the upright switch has a low enough profile).

[themanfromsaturn]

I have a similar issue on one of my PAL Saturn consoles with wobbly video.

zyrobs, in regards to recapping the mainboard, what's the recommended way to remove the capacitors? I've tried using a soldering iron and basic solder sucker before, but it wasn't really up to the job.

[zyrobs]

I think I just used a wide chisel tip to heat both ends of the capacitor on the back of the board, then I pulled it out from the front. Removing the EMI filters was more difficult though, I don't remember how I did that.

The proper way to do it is probably using a desoldering gun (the one which is a soldering iron with a vacuum pump nozzle built in).

[Sega Fanatic]

hello thanks i have normal spdt toggle switch On-On 3A , 3 legs
i whant to install the mini slide switch because then no need use wires
what is diference some switch say On-On others On-Off both work ?
I only need to connect 2 legs on switch ?

[zyrobs]

On-On switch means that the switch will alternate between connecting the middle+left leg, or the middle+right leg.
On-Off switch means that the switch will alternate between connecting and not connecting two legs only.

The SW4 point on PAL Saturns is outfitted with a pulldown resistor. That means that it has the VDP2 50/60Hz switching pin grounded through a large resistor. When you feed 5V to it through the SW4 point, the electricity will follow the point of least resistance and ignore the ground connection behind the resistor. This is good because then the pin is never left "floating", it is always either low (connected to GND) or high (connected to 5V).

So technically the only thing you need is a way to open/close the middle two pins of the SW4 point. On-off switch works, but on-on also works because of how the pins are laid out (GND - common point - 5V).

[patters]

Hi, my VA9 PAL console has picture wobble that starts out quite noticeable but then calms down as the components warm up. I recently took the console apart and took a look at the caps and there was no swelling, or conspicuous doming of any cap even on the PSU board. So, is the cause of the wobble still relatively unknown, or is there a particular cause?
I also notice image wobble during loud optical drive seeks.

[zyrobs]

Jul 11, 2020 23:43:34 GMT patters said:

Hi, my VA9 PAL console has picture wobble that starts out quite noticeable but then calms down as the components warm up. I recently took the console apart and took a look at the caps and there was no swelling, or conspicuous doming of any cap even on the PSU board. So, is the cause of the wobble still relatively unknown, or is there a particular cause?
I also notice image wobble during loud optical drive seeks.

Electrolytic capacitors have a finite lifespan (the electrolyte liquid inside dries up), and Saturns are old enough that the caps are weaker, even without any outward signs of trouble. Since they are mostly used for filtering, the weaker caps end up causing shaky picture or generally unstable operation (which starts slowly going away once the caps "warm up").

So yeah, you'll need to recap the console. This is a very common problem with VA9 PAL units, very nearly all the ones I had suffered from this.

[patters]

Thanks. I had wondered, since VA9 boards seem to suffer particularly with wobble, whether there were perhaps a few specific caps that could be tackled without replacing the whole lot.

Now that I have taken a closer look I also see that there are a great many of those EM filter devices too, which I believe are also a type of capacitor. Previously you posted a suitable replacent part code manufactured by Murata but that appears to have been discontinued. Do you perhaps have details of a modern equivalent part? It seems odd that Console5 would seem recap kits for instance, but leave these out. Also, are they all the same? There is a long row of them at the back of the motherboard near the AV port, but also there are many at the front of the board too.

[zyrobs]

The last time I did a recap I also replaced the EMI filters but only on the ones on the video output part. I haven't tested before or after changing them though, only after I changed out all the caps plus that half of the EMI filters.

I don't know what is the currently available correct replacement part. I still have a bunch of those old ones which are a bit too thick to be used but can make do if you angle them a bit. There was a thread where we talked about it:
segasaturngroup.proboards.com/thread/11508/emi-filter-source

[semaj]

I have a Saturn VA9 PAL console with an issue where there is slight horizontal glitching when the laser assembly moves/seeks. It's only a couple of lines here and there in the middle of the screen. Sounds very similar to what you're talking about above.

I've replaced all the capacitors - main board, PSU, and the optical drive board - and I've also replaced the EM filters. Still getting this interference on the video output.

I'm pretty sure the interference has been reduced but now I see it maybe I will never unsee it!

Is this just something we have to live with or did you guys solve this problem on your consoles?

[zyrobs]

In the last console I recapped, it took a little while for those lines to disappear even after recapping. However, after recapping they at least disappeared eventually. Also the colour output of the console improved a lot.

You could also try using one of those aftermarket power supplies, or putting extra caps on the empty pads of the motherboard - the latter helped me, but unfortunately I don't know the exact capacitance you should use for filtering. Someone with an oscilloscope would need to measure the frequency of the screen wobble.

[semaj]

Appreciate the response. The additional capacitors was something that crossed my mind and now you've mentioned that helped I'll look into that more seriously.

[jamesofmercia]

Good afternoon and good news everyone! I've solved your problem for you.

After a week of feverish experimentation I've successfully concluded and tested that it was infact the X1 Crystal oscillator at fault.

This is very good news as the part is easy enough for an experienced modder to replace and if you wanted to convert the unit to true NTSC output while you're installing a region mod you'll kill two birds with one stone.

The part is easy enough to buy off eBay, 14.318mhz for NTSC, 17.734mhz for pal