Sega MegaDrive 2 50/60hz and Region Single Switch Mod.

I know there have been many threads on the more commonly know 2 switch 50/60hz and region mod for the MegaDrive 2 system but there doesn't seem to be hardly any guides on the newer less know single switch mod, so today i thought i rectify this for anyone wanting to do this fairly simple and clean mod on their MD2 console.

There are only 3 areas we need to be concerned with on the MD2 mainboard (only 1 of them being slightly problematic than the other 2) and i should stress this is for the VA0, VA1 and VA1.8 revisions of the MD2 system and i cant say if the layout is the same on the later revisions but i shouldn't see why not.

The first area we want to look for is just above and to the right of controller pad port 2 (usually there is a 'Q.E Pass' sticker around this area) and its this area here and the solder pad circled in red......



This pad leads to Leg 107 on the main large chip which needs to be isolated, this 107 Leg controls the region language of the MD2, positive current makes the MD2 JPN language and negative (ground) selects ENG language. Now older guides suggest lifting this leg from the mainboard and soldering a wire to the leg but this is extremely difficult and usually result in the leg getting snapped off just due to how delicate, small and the tiny amount of work space you have to lift the leg. The best option is isolating the trace leading to the leg from the rest of the MD2's mainboard and we do this by cutting across the trace, cut just above the solder pad like so with a fine utlity knife.....



and then next we want to ever so carefully scrap the coating of the trace just north of the cut we just made until we expose the copper conductor underneath, be very careful not to apply too much pressure as it doesn't take a lot to scrap the coating off and be wary of the other traces either side as well as we don't want to take the coating of these traces......



The area we have just scrapped the coating off from is going to need solder applied to it so with your solder iron start to heat this copper trace area for a few seconds and then with the iron still in contact with this exposed copper trace apply solder to the very end of the tip of the solder iron and the copper trace itself, if the exposes copper is hot enough the solder should flow on to this copper, you don't need a great deal of solder just enough to cover the copper......



You have now completed the most difficult part of the mod.

Now we want to tint your wire that we will be soldered to this leg 107 trace, so add some solder to the wire and then place the wire on top of the solder we just added to the copper trace in the previous step and get your solder iron and press down on the wire. Because we have previously added solder to the copper trace and the wire itself when we add pressure to these 2 with the solder iron then they will adhere to each other when they get hot enough and make a secure solder connection, like so....



Now we want to locate the area just the opposite side of this main large chip and leg 46 and its trace is what we are after. Look for this small trace circled in the red, we are wanting to cut this trace as we did before with the trace for Leg 107, be careful not to cut any other traces nearby and just this small trace leading to the cluster of solder pads just above it.......



These cluster of pads are providing ground to Leg 46 of the large chip at the moment and this tells the MD2 what HZ to run games at (50hz or 60hz) as this trace is still intact at the moment its providing ground to Leg 46 of the chip and telling the MD2 to run in 50hz mode, if we were just to cut this trace and leave it then Leg 46 would no longer be getting ground and would switch the MD2 to 60hz. After we have cut this trace we need to solder another wire to the lower pad of a pair of pads labeled 'C 8' just above and to the left of the trace we just cut, like so.....



The last wire we need to solder is a simple 'through hole' solder point and its 'JP 3' located above and to the left of the 'C 8' pad we were just working on, there is a large metal heat sink nearby to help you identify the area......



As before tin your wire with solder and with the solder iron in one hand and the wire in the other heat the solder in the solder hole for 'JP 3' and when the solder starts to melt push the wire through the hole and remove the iron, this will then create a secure solder point. Check the underside of the board and cut off any excess wire/solder poking out to avoid any ground issues....



Now time to solder the 3 wires to the switch. The switch you will want to use is a 3 position ON-OFF-ON slide switch.....



The way i have my switch wired is position 1 is US NTSC, position 2 JPN NTSC and position 3 ENG PAL. So solder the wire that is soldered to the trace of 'Leg 107' (Purple wire) to left leg of the switch (if looking at the switch with the legs facing you), the wire soldered to pad 'C 8' (Grey wire) to the middle leg of the switch and finally the wire soldered to 'JP 3' (White wire) to the right leg of the switch. Please remember to use the same row of legs on the switch for all 3 wires like so......




I position the switch on the left side of the console and under the curved edge its nice and discrete....




Cogratulations you now have a single switch 50/60hz & Region modded MD2 consoles!!!

 

Hey nice guide. Don't think I've ever seen guides that uses the 3. pos switches either, but I've been doing that for years too

I do things a little different and use pull-up resistors on the switch like so:


Two 1K resistors are soldered to the outer pins and twisted together. 5V (red wire) is soldered to the resistors, GND (black) is soldered to the middle pin, 50/60Hz select is soldered to one outer pin (green) and Language select (yellow) is soldered to the other.

That gives me 50Hz(ENG), 60Hz(ENG), 60Hz(JAP) in that order.

You can also use the same method on the second row of pins on your switch to add a tricolor LED that changes colors according to the region. 1K resistors work well here (higher would make the LED too dark).

Here's an example from my Mega Drive 1:

 

Yes adding pull up resistors can stop any "funkiness" happening (TmEE guided me on that. He had issues, I never did but do it now just to be safe).

Tri-colour is sweet too! I use blue and red to get blue/red/purple. Just took a bit of messing around with resistors to get the balance right.

 

Thanks for the heads up on the resistors, so what do these resistors actually do??

So to confirm from your picture, 1k resistor solder to each outer pin on the switch and then connected together and then the 5v wire (JP 4 in your case and C 8 in mine) soldered to resistors, ground of JP 3 soldered to middle pin, hz wire to one outer pin and lang to other outer pin?. So yours uses a 4 wire solution.

Im liking the LED mod as well

 

When the switch is in the center position the resistors "pull up" the 50/60Hz- and the Language-wires to 5V. If the switch is to either side, one line will have a direct connection to GND and the resistor will prevent a short between GND and 5V. The other wire will then be pulled high by the resistor.

If you switch the 5V and GND wires then the resistors will act as "pull-down" resistors and pull them down to GND instead But that wouldn't make sense in this case as you would end up with something like 50Hz(JAP) if I'm not mistaken

Normally it's not advised to keep the wires floating without any connection to either GND or 5V. In some (most?) cases the system will just assume that no signal = 0, but it's best to have a connection to GND just to be safe

Yes that is correct

 

Thanks, ill guess ill add the resistors on my switch. Ive not had any issues at the moment but i guess its best to add them for safety.

So for my install where i have soldered to C 8 is that replaced with JP 4 or the other JP 3 pad in your method?.....i was under the assumption that 'C 8' was providing ground?

Im guessing i just need to solder another wire to JP 4?

 

You can get GND and 5V from lotsof places. I just like to use the through-hole connections as it makes it look neater IMO If you are unsure if something is GND you can use a multimeter, and measure the resistance against one of the points that run along the edge of the PCB.

I'm pretty sure that the pad near you soldered near C8 is GND. Which means that when you have your switch in the off-position (middle) the MD assumes the wires are high (as in 5V). I would have thought it would have assumed low

 

Well the actual C8 pad ive already solderd to is ground and the north pad of C8 is actualy positive...but seems to be considerable more that 5v. JP4 seems to be in the region of 3.9v and that north pad of C8 seems to be 11.5v. Unless im reading it completely wrong on the MM.

So im not actually pick up a separate 5v from anywhere with the way i have it wired currently??

 

Nope. The middle leg is ground and the other two are the jumpers that select either 50/60Hz or Language. And since your mod works, it means that without any connection these jumpers will pull themselves high

 

https://scontent.xx.fbcdn.net/hphot...836_856450494475209_6057983623734953394_o.jpg

I made cut traces on the spots marked with red but when i try to turn on my console it didnt start up just say no signal on Rf and on Av too . What should i do please help me

 

Sorry to resurrect an old thread with a possibly stupid question or two, but I'm wondering... what gauge/type of wire (& solder) would you folks recommend for this mod?

Also, @Bearking : I'm intrigued by your tri-colour LED mod! Would you be willing to share your technique with me please?