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nigelicious
1st September 2008, 10:50 AM
Picked up a Megadrive 1 to play with, looking to have a crack at the full list of mods located at this site : http://www-unix.ecs.umass.edu/~dhowland/mod/

All of the parts required look reasonably easy to find from Jaycar/DSE, except for the "9.216MHz TTL oscillator (Digikey: X113-ND)". Having a look on their respective website, can't seem to find ANY oscillators of this style. Can see them on US sights but it seems a little ridiculous the shipping and quantities required - and I find it hard to believe I won't be able to find one locally.

Total electronics n00b here so I may be missing something - any advice from the ele-geeks?

AdamC
1st September 2008, 11:46 AM
Hey what great mods .. i remember connecting a 3.5mm plug - 2 RCA lead to my tv to get stereo sound. Wish these mods were available when i had my megadrive.

What mods are you going to do to it ?

AskJacob
1st September 2008, 11:56 AM
I have a whole box of crystals and oscillator modules - PM me to remind me when I get home to check for you.

Cheers
Jacob

nigelicious
1st September 2008, 11:59 AM
Will do Jacob, thanks!

Adam - I'm planning to *try* and do all of the mods on that page :)

My soldering skills are attrocious (just ask Tony, I did some for him yesterday :lol) but it looks like a pretty simple set of mods to do.

My only concern is that I've read somewhere that overclocking the CPU has issues with some games ... and I've read you can install a switch but cant really see how that can be done considering the method on that page puts a hole in the board from the onboard clock.

David_AVD
1st September 2008, 01:23 PM
My soldering skills are attrocious (just ask Tony, I did some for him yesterday :lol)

Remind me not to buy that machine! :o

nigelicious
1st September 2008, 01:54 PM
Remind me not to buy that machine! :o

It was one dab of solder, I overstate the fact a little. Certainly alot less than what i'm about to do here!

dmworking247
1st September 2008, 01:59 PM
Those are great mods, I want to do that one day (I have two first gen megadrives). I think the SVideo is a bit out of my league though, I would have been happy with a simple PAL RCA out, I *hate* those RF tuners.

AdamC
1st September 2008, 02:29 PM
I pretty sure I used an old plug that fitted into the large socket on the right side of this pic.
That went into the video input of my tv.
http://www-unix.ecs.umass.edu/~dhowland/mod/images/finishedrear.jpg

elvis
2nd September 2008, 08:50 AM
I pretty sure I used an old plug that fitted into the large socket on the right side of this pic.
That went into the video input of my tv.

Same, but they're hard to find these days as they're not very popular.

Doing these mods means you can just buy an off-the-shelf set of RCA and S-Video cables.

I did the same A/V out mods on a mate's Sega Master System (http://www.stickfreaks.com/smsmod.php), and it came out a treat. Picture quality is fantastic.

The next one I do will be an RGB out mod straight to an arcade monitor.

AskJacob
2nd September 2008, 09:02 AM
Sorry mate, I didn't have a 9.216 module...

Have a 10.000 but I guess the odd value of 9.216 was picked for a specific timing reason...

www.rockby.com.au only have a 9.6 module

I can't seem to find the modules at my usual aussie suspects...

Cheers
Jacob

narf_
2nd September 2008, 07:57 PM
that plug looks like a commodore plug

dmworking247
2nd September 2008, 08:14 PM
Same, but they're hard to find these days as they're not very popular.

Doing these mods means you can just buy an off-the-shelf set of RCA and S-Video cables.

I did the same A/V out mods on a mate's Sega Master System (http://www.stickfreaks.com/smsmod.php), and it came out a treat. Picture quality is fantastic.

The next one I do will be an RGB out mod straight to an arcade monitor.

But wait... if there was originally a cable/plug that allowed you to get an RCA video out into a PAL TV, then shouldn't you be able to find the two associated pins on the inside of that round socket that you need to syphon off a dedicated RCA output?

nigelicious
2nd September 2008, 08:43 PM
But wait... if there was originally a cable/plug that allowed you to get an RCA video out into a PAL TV, then shouldn't you be able to find the two associated pins on the inside of that round socket that you need to syphon off a dedicated RCA output?

There is only an RF out on the SMS2. I do believe the European SMS2 had the scart. The chip however still has the capabilities - hence the hack.

Ryan555
2nd September 2008, 10:02 PM
Same, but they're hard to find these days as they're not very popular.

Doing these mods means you can just buy an off-the-shelf set of RCA and S-Video cables.

I did the same A/V out mods on a mate's Sega Master System (http://www.stickfreaks.com/smsmod.php), and it came out a treat. Picture quality is fantastic.

The next one I do will be an RGB out mod straight to an arcade monitor.


I remember in the very late 90's someone showing me a whole heap of arcade cabinets with multiple Megadrives inside them, they were hooked up via RGB to the Arcade Monitor. There were also lots of dodgy custom PCBs (Vero board) with relays that enabled you to switch different games and accept coins to start play. The cabinets were being stripped for parts.

I have a Sega Nomad (hand held Genesis) that I have hooked to an Arcade Monitor (just because I could) :)

Here are some links for RGB out.

http://members.optusnet.com.au/eviltim/gamescart/gamescart.htm#megamstr
http://www.mmmonkey.co.uk/console/sega/md-stereo-scart.htm
http://www.mmmonkey.co.uk/console/sega/md2-scart.htm

elvis
3rd September 2008, 08:15 AM
But wait... if there was originally a cable/plug that allowed you to get an RCA video out into a PAL TV, then shouldn't you be able to find the two associated pins on the inside of that round socket that you need to syphon off a dedicated RCA output?
There was in the Megadrive. You still need to go and buy a 5-pin DIN cable, and hack it up of course. And if you lose the cable, then you gotta do it all over again.

As mentioned, the Master System 2 only had RF-out. No A/V-out at all.

Hack RCA-out direct onto the console, and the functionality is always there, ready to go with off-the-shelf cheapy cables.

dmworking247
3rd September 2008, 08:49 AM
I must be missing the point.

Why would I need an 5-pin DIN cable, is there actual circuitry in the cable or is it just 5 wires? If its just wires, why cant I solder two wires to the right pins on the INSIDE of that connector to a female RCA jack.

I must be confusing my terminology between RGB,SCART,RF-OUT,AV-OUT,SVIDEO etc.

elvis
3rd September 2008, 10:18 AM
I must be missing the point.

Why would I need an 5-pin DIN cable, is there actual circuitry in the cable or is it just 5 wires? If its just wires, why cant I solder two wires to the right pins on the INSIDE of that connector to a female RCA jack.

I must be confusing my terminology between RGB,SCART,RF-OUT,AV-OUT,SVIDEO etc.

There's two separate conversations going on here.

1) MEGADRIVE: The Megadrive 1 had a 8-pin DIN slot in the back, allowing RGB and Composite video:
http://www.gamesx.com/avpinouts/genesisav.htm

You can solder direct to them if you like (as you've mentioned above). You can also make yourself a DIN->RCA breakout cable (why? because it would be neat and tidy - no need to break open the console and drill into your case). You could also solder direct to the CXA chips on board if you wanted to, if you were that way inclined (why? because you bloody well feel like it).

However: you couldn't get S-Video off it, as there's no separate Y and C signals, only composite video. If you wanted S-Video, you'd need to get the signal direct off the CXA chip inside.

If you want to do overclocks (stops newer games crashing), or 50/60Hz mods (full speed games, not PAL handicapped), then you'll still need to solder onto the CXA chip.

2) Master System 2: the SMS2 only had RF-out. You can't do shit with that. You had to bust the console open and take the signals off the CXA chip inside the unit. That was your only choice for A/V out mods.

Davefjedi
3rd September 2008, 10:54 AM
HOLY CRAP BATMAN (http://cgi.ebay.com.au/SEGA-MASTER-SYSTEM-2-MODIFIED-AV-S-Video-more_W0QQitemZ260278816471QQihZ016QQcategoryZ36618 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)
Anyone want to give me their old SMS2 systems
I know what Im looking for at garage sales now

elvis
3rd September 2008, 02:00 PM
HOLY CRAP BATMAN (http://cgi.ebay.com.au/SEGA-MASTER-SYSTEM-2-MODIFIED-AV-S-Video-more_W0QQitemZ260278816471QQihZ016QQcategoryZ36618 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)
Anyone want to give me their old SMS2 systems
I know what Im looking for at garage sales now

Like he'd sell any.

Davefjedi
3rd September 2008, 02:22 PM
Like he'd sell any.

Check his feed back has sold a few:o

Hewitson
3rd September 2008, 03:46 PM
Of course some wanker had to ask him if it comes with "alex the kid". :x

Why the **** can't people read the title of this game correctly?

elvis
3rd September 2008, 07:30 PM
Check his feed back has sold a few:o
I'm honestly amazed. It goes to show how many ****ing stupid people there are in the world.


Of course some wanker had to ask him if it comes with "alex the kid". :x

Why the **** can't people read the title of this game correctly?
One of my pet hates. Can't anyone get that goddamn title right?

Virgil Tracy
3rd September 2008, 07:50 PM
Anyone want to give me their old SMS2 systems
I know what Im looking for at garage sales now

Me too:o

Arcade King
3rd September 2008, 08:20 PM
Will do Jacob, thanks!

Adam - I'm planning to *try* and do all of the mods on that page :)

My soldering skills are attrocious (just ask Tony, I did some for him yesterday :lol) but it looks like a pretty simple set of mods to do.

My only concern is that I've read somewhere that overclocking the CPU has issues with some games ... and I've read you can install a switch but cant really see how that can be done considering the method on that page puts a hole in the board from the onboard clock.

i reckon if your gonna overclock rip a 16 mhz 68000 off some crappy arcade pcb so she can handle it ;)

nigelicious
3rd September 2008, 10:10 PM
i reckon if your gonna overclock rip a 16 mhz 68000 off some crappy arcade pcb so she can handle it ;)

I bought a 10mhz crystal.. hope itll work