60hz mod on Pal Saturn, some issues

I have a Model 1 PAL Saturn with revision VA01 motherboard. It has the SW4 jumpers near battery compartment, and also the JP1 Jumpers on back of motherboard.

I tried soldering together the two middle SW4 Jumpers through switch, and yes it does output in 60hz, but the image is garbled, as if it is trying to display a 50hz output at 60hz? Maybe the display processor isn't getting the memo? Crystal Oscillator is wrong? If I do the switch as a game is running, then the Saturn freezes but the 1 frame it freezes on ends up displaying correctly in NTSC mode.

I thought the Sw4 jumpers/JP1 go straight up to pin 79 on the VDP? I won't have to break that damn pin will I? Is there an additional line leading up to this pin I need to sever/break somewhere? Why would Sega include SW4 jumpers in battery compartment if they're useless?

I found this in an old 2009 thread on your forum, does this apply to me?

I cannot into electronics and may have bought the one PAL Saturn on the planet with a dud motherboard revision where this easy mod is not easy to do. Story of my life.

Also from old thread:

The image link doesn't work, this guy seems to know where to cut/what to do in this situation, but the links are broken sniff.

Old Thread Link in case any of these users still active: http://assemblergames.com/l/threads/pal-saturn-60hz-mod-made-simple.20598/page-4

 

It's expected behavior the way you've done it.

If my memory is correct pin1 of the PLL chip that delivers the clocks to the processors makes it switch between 50 and 60hz modes but both of those modes require a different crystal. This causes the system to run at the wrong speed.

What you need to do is either lift pin1 of the PLL or sever the trace going to it.
You want the PLL to stay in the same mode as it currently is and only switch VDP2 pin79.

Alternatively you can perform the 50/60hz mod by lifting pin79 of VDP2 and attaching your switch to that. (very delicate and easy to mess up) This method works on any Saturn no matter the board version.

Essentially i'm just echoing what that one quote said, the easiest way is probably to lift pin1 of the PLL and tie it to ground with a wire.

 

Thanks for the valuable info.

I may have tried this had I not ordered an NTSC-J SS console anyway this morning. In the interests of posterity I'm building a retro collection and will keep this PAL console around as it is. I have an action replay so imports/regions aren't an issue.

I suppose I'll build my Saturn collection around US and Japanese games. Keep the PAL console around as a decorative piece and for the handful of European exclusives. It is in near-mint condition so as a collectors item it will hold value.

 

That will of course work too.

On the plus side that will give you a fully in spec NTSC signal while a PAL console running at 60hz depending on your tv or scaler may stutter or have wonky black levels.
CRTs did not have any issues with that but our modern gear is a bit picky.

 

Cool did not consider that, probably minor things but it becomes noticeable on lcd tv's these days.

I tend to stick with original console revisions because they tend to cut back on features as they miniaturize and move into higher production yields. I've heard rumours that the model 1 Saturns output slightly better video signal/audio but not sure if true. Regardless the Japanese model 1 grey and model 1 in west just look better.

 

From my experience the model 1 Saturn does indeed have a slightly sharper image. It's a minor difference though as the Saturn has excellent RGB overall

 

Good to know.