Adding a 50/60hz switch to Megadrive

[morpheus21]

Hi,
as this is my first post just want to say what a great site this is!
I'm after some info on how to add a 50/60hz switch to my Pal Australian Megadrive 1 and 2. Have searched the net on google but have not been able to find any decent info. Some pages tell me how its easy to do the megadrive 1 and the info on how to has been on the web for years but I haven't been able to locate it. Am really wanting to add a switch as am sick of playing the games with black bars on top and bottom of the screen instead of having it fullscreen like it is ment to be played. Links to web pages or direct info on how to do it would be greatly appreciated.

thanx

[Zebbe]

This is absolutely the best guide: http://users.skynet.be/DuNe/Console/md1/md1.html

After you have done it, you'll never wanna go back. :)

[morpheus21]

thanks alot for that. any more info out there for a mega drive 2?

[Zebbe]

http://users.skynet.be/DuNe/Console/md2/md2.html

This one is harder, while the first one is easy. I haven't done this mod.

[morpheus21]

thanx again. I wont be doing the modding will be getting my brother to do that. he has done similar things so hope this will be no problem for him. cant wait to get it done now.

[Zebbe]

I let my neighbour do the 50/60 Hz-mod and then I did the Eng/Jap mod myself. :)

[Elusive]

I let my neighbour do the 50/60 Hz-mod and then I did the Eng/Jap mod myself. :)

I did it all myself. Was I ever surprised to learn my Mega Drive II was created on my sixth birthday. It's like we were meant to be. Serously, near the CD connector there should be a date stamp of the day it was created. 5 Aug 1993, bitches =P

The hardest thing I found was soldering the wires to the finicky pins. I ended up doing this:

http://img197.imageshack.us/img197/9282/bend3db.gif

Cut twice the amount of wire needed, bend it over. Then:

http://img512.imageshack.us/img512/769/applied8ce.gif

Place it over the chips' wires you lifted up. The solder then naturally wants to stick between the three strips of wire, making it a lot stronger, and more secure. It's also easier and neater than making a huge solder blob and hoping for the best:

http://img512.imageshack.us/img512/9210/stuck7vl.gif

as opposed to

http://img512.imageshack.us/img512/9213/ohfuck5xb.gif

[Elusive]

My experience with a MD2:

(assuming you have taken off the shell and the metal shielding and stored it safely without maiming yourself. Directions like bottom-right assume you have the controller ports facing you - in this case bottom-right would mean the closest part of the console to your body and your right-hand side)

50/60Hz mod:

step 1

http://img261.imageshack.us/img261/5717/11tj.gif

a) Lift up the third pin from the bottom-right. I used a paperclip to detach it gently by pulling up and away from the board, then used pliers to straighten it out fully. It's a bit flimsy, do DO NOT PULL TOO HARD at any point or it will come off.

b) See the trace the third pin was attached to? It should go to a wierd hole thing. In my diagram, the hole is represented by grey to avoid confusion with the black of the chip. The green stuff surrounding the hole is what you want to scrape up. You can use a razor blade to do this. Neatness only matters as long as you don't mess up the surrounding circuitry. You should aim to make it impossible for current to pass to the hole by scraping at the green stuff.

Now, solder a wire to the sticking-out third pin of the chip, using the bend-over method I showed in my previous post. Practise on a spare bit of wire to make sure you can do it, though.

Oh, and as always when soldering, have a second pair of hands ready - that way you can hold the wire and the soldering iron, they can hold the solder. Saves you getting hot and bothered and angry and frustrated aligning and taping down the solder and wire beforehand.

Also, cut a lot more wire than you need. Nothing's worse than soldering a wire only to find it's that little bit too short. Sodler first, then cut to size.

step 2

http://img156.imageshack.us/img156/2893/29vr1.gif

Find a spot on the bottom-right of your console with the little solder dots. Put a blob of solder onto one, then attach a wire to the solder. Bingo, that's your Ground wire. (ignore the colour of my wire)

BEWARE: make sure you will be able to fit the metal sheilding back over your wires! I tested this by using tape before soldering - I taped down my wires where I wanted them to be and tested whether I could put back the RF shielding or not.

step 3

Remember the green stuff we scraped away in Step 1 around the hole?

http://img427.imageshack.us/img427/9704/36sg.gif

Put a dollop of solder on it, so the line that came from where the third pin was connected can make contact with the solder. Add a wire to this.

OMG CONCLUSION STEP 4

The wire from the third pin in step one is the important wire. It goes to the middle of the switch. The other two wires go to either the right or the left side of the switch. Make sure you can tell which wire is connected to which point on the Mega Drive, though.

Without putting the top back on you can now plug it in and test it with a game in! Wheeeee!

The result will be if you connect the middle part of the switch - the third pin, OK? - to the wire that comes from the hole you scraped around, it'll produce a 60Hz display. If you connect it to the other wire - the Ground connection - it will produce a 50Hz signal. If you've got an odd console, it might be the other way round.

Oh, and remember to account for how you will fit the switch to the outside of your machine! I didn't, and I had to squish the too-long wires around inside my machine after I'd secured the switch :(

I might do the Jap/Overseas switch in Paint some other time, it's the most difficult.

[landstalkerx]

There is another way of doing the mod to a genesis 2, following the same principals, which I consider to be easier. I've done the mod twice. I'll post pictures later today, when I get a chance.

[landstalkerx]

US/JAP switch

The first step is to locate pin 107 Then follow the lead that comes off of pin 107 until it gets to a hole in the board. (blod of solder in pic)

Pic 1 (http://kenyonfamily.net/steve/pic1.jpg)


Follow the through hole to the opposite (bottom) side of the board. The objective is to seperate the hole (lead from pin 107) Cut through the copper using an exacto knife. DO NOT CUT ALL THE WAY THROUGH THE BOARD. Just until you see white. You can use a continuity meter to make sure you’ve isolated the hole.

Pic 2 (http://kenyonfamily.net/steve/pic2.jpg)

Flip the board back over and scrape around the through hole, to remove the protective coating. Do Not sever the lead to the hole. The idea is to create a place that you can solder a wire to. After this is done, solder a wire to this point/hole, as in the first picture. This wire goes to the middle of your switch.

The other two wires should go to the right side of L4 and the Left side of L3. L3 and L4 should already have some solder in them so this shouldn't be difficult.

Pic 3 (http://kenyonfamily.net/steve/pic3.jpg)


50/60 switch

Locate pin 46. Follow the lead until it splits into two, right by the white "52" printed on the board. Use an exacto knife to cut the lead that goes up towards the cart slot at the junction. Leave the other half intact (the half that goes towards the left.)

Pic 4 (http://kenyonfamily.net/steve/pic4.jpg)

Now for the second switch. solder the middle wire to the left side of JP3. Solder another wire to the right side of JP3 and antoher one to the right side of JP4. the other end of these wires should be soldered to the other two terminals on the switch.

Pic 5 (http://kenyonfamily.net/steve/pic5.jpg)

Overview Picture (http://kenyonfamily.net/steve/segamod%20002.jpg)
Another Overview Picture (http://kenyonfamily.net/steve/segamod%20006.jpg)

If you need any aditional pictures or explaination just ask!

[Joe Redifer]

Are you guys using 4-pole double throw switches? Where are you getting these? I could only find 2-pole single throw switches when I modded my Saturn with a US/JAP switch, and as a result I had to use two separate switches.

[landstalkerx]

I bought my switches at fry's electronics. They aren't "4-pole double throw switches" though. They've got three solder points. ie. on-on. So theres one switch for the 50/60 and one switch for the US/JAP setting.

[Joe Redifer]

I don't have a Fry's up here in Denver. I wish I did. The closest thing we have is Radio Shack. But we do have specialty electronics shops that might have what I am (was) looking for. With the Saturn, 1 jumper was on and the other off for USA mode, and for JP mode they were opposite.

[landstalkerx]

Actually to tell you the truth, Fry's isn't a speciality electronics store, I don't know where any of those are in San Diego, because I haven't lived here very long. Fry's is a huge (costco size) all purpose electronics store that sells everything from dishwashers to resistors to Hard drives.

[Joe Redifer]

I've been to Fry's in Dallas so I know what they are and you are lucky to have them in your city, but my city only has Radio Shack and some mom and pop stores that sell things like switches, diodes, capacitors, resistors, transistors, etc. Maybe Fry's will expand to Denver someday.

[Elusive]

Are you guys using 4-pole double throw switches? Where are you getting these? I could only find 2-pole single throw switches when I modded my Saturn with a US/JAP switch, and as a result I had to use two separate switches.

No, I'm using break-to-make single-pole double-throw switches that look like this:

http://img66.imageshack.us/img66/3153/switch0qr.gif

In my diagram the blue wire goes to the leg of the third pin from step 1, the Ground wire and the wire coming from the hole on the board go to the other legs of the switch.

This means I am using two seperate switches for the 50/60Hz mod and the Jap/Overseas mod.

[morpheus21]

got my modded mega drive back the other day and it is great. brother added direct rca video and stereo out aswell. apparently it is a jap megadrive that was modded to play pal. huge difference being able to play the games fullscreen instead of letterboxed. couple of games incompatible with it though - samurai showdown screen scrolls as though v-hold is screwd and another world the top part of the image flickers but other than that no real complaits. does anybody know of any other games that wont work?

[Zebbe]

There are many. Virtua Racing for example, it flickers.

[morpheus21]

damn, am bidding on that game at the moment on ebay!

[Zebbe]

I try to buy the US/Jap version in most cases were you have the lockout-chip. But I had PAL VR many years before I modded the console.

[Elusive]

got my modded mega drive back the other day and it is great. brother added direct rca video and stereo out aswell. apparently it is a jap megadrive that was modded to play pal. huge difference being able to play the games fullscreen instead of letterboxed. couple of games incompatible with it though - samurai showdown screen scrolls as though v-hold is screwd and another world the top part of the image flickers but other than that no real complaits. does anybody know of any other games that wont work?

You've got an Asian machine there, pal - it's designed to work in the areas of the East that run at 50Hz (as opposed to, say, Japan which runs at 60Hz). You've basically got a PAL machine in a Japanese case.