Fix off-spec refresh of 60Hz modded PAL Mega Drive?

[ASDR]

I know that a modded PAL console does not run at the correct refresh when in 60Hz/NTSC mode. Works fine with my current TV but I'm worried about future incompatibilities with the OSSC/Framemeister/new TV. Can I fix this by simply replacing the oscillator? Is that a standard part I can just buy and drop in? I know this will likely make the console off-spec when running in PAL mode, but I'm not terribly concerned about that.

[Kez]

Yes you just need to replace the crystal with a 53.693175Mhz one and the console will be effectively NTSC. As you say, any issues you had in NTSC will be transferred to PAL mode. I picked some up on one of those chinese export websites and have installed them in 3 mega drives without issue.

If you are a perfectionist you can also replace the crystal with a DFO (dual frequency oscillator) (http://nfggames.com/forum2/index.php?topic=5744.0) and wire it up to your switchless mod so that the frequency is correct for both modes. As I almost exclusively play my games in NTSC anyway and the PAL issues are fairly minor, I think the straight crystal swap works fine for me.

[ASDR]

Good news!

I don't really care that much about the handful of PAL exclusive games that are problematic on NTSC consoles (if there are even any), so a simple swap would be OK.

How do I find the correct crystal? Can you let me know the mode number etc. of what you used? I'm betting the thing labeled with '53.203Mhz' is the crystal on my motherboard, the replacement will have the same package / pins?

Sorry for the newbie questions, new to all of this, willing to learn.

[Kez]

If you search for "53.693175Mhz" with no spaces on aliexpress then any of the results you find there should work fine. I wasn't able to source any locally (UK). Just make sure it has four legs.

It is just a straight swap, all you need to do is make sure the orientation is the same.

[ASDR]

I also tried to look at the usual UK at German stores, didn't find any. But Aliexpress is perfectly fine. Looks like a very straightforward task.

Shipping from China is also no problem. I'm in no rush. MD works fine right now. My HDTV is a gentle old soul that takes 240p with off-spec refresh rate no issue. I bought an OSSC and should get one next month, I've heard it's a bit more picky. Good to be on the safe side.

[BuckoA51]

We have some dual frequency oscillators in stock you may be able to adapt for that.

[ASDR]

Ah neat, never noticed those in your store! I ordered a batch from Aliexpress yesterday. Since I doubt I'll be needing PAL output very much, just replacing the crystal seems like the simplest thing to do.