Master System MK-2000 RGB output

[zinger]

Just picked up a Japanese SMS, with only an RF cable included. Heard the RGB signal is weak on this model or produces a dark picture with a MD RGB lead?

https://otakus-store.net/en/accueil/12- ... stem-.html

I’m thinking of picking up one of these, but wanted to ask around first since it’s a bit pricey… hoping somone on here has experience with this cable or any alternatives?

(I’ll be connecting it to an OSSC pro.)

[SGGG2]

I'd just wait for the SMS Lumacode module to get released. It's being finalized as we speak.

[jd213]

Looking forward to Lumacode on more systems, but it might be a while before all the SMS variants are supported.

Pretty sure a MK-2000 just needs a Genesis/MD RGB cable without in-line resistors or capacitors installed (don't think it needs an amp like the one in the above link), so it should be fairly easy to make a custom cable.

[RebeL9]

I have a Master Syster MK-2000 and bought that exact cable from Otaku. It’s a very high quality cable. Thick and very sturdy. Never experienced anything wrong with it.

[zinger]

Thanks for your input.

Here’s the info that got me worried about its RGB:

https://consolemods.org/wiki/Master_Sys ... tput_Notes

The Japanese Master System (often referred to as the MK-2000) does not require any components on the CSYNC line. When connected to a display or processor, it will output around 350 mV without anything else needed. In fact, all four lines (red, green, blue and sync) all have the necessary components on the motherboard, so the RGB cable will just be a full pass-through cable. This is the opposite of all other SMS revisions, and using RGB cables meant for these consoles on the MK-2000 will result in a dimmer picture. The HD Retrovision cable can compensate for this with its contrast switch, but this can pose a problem otherwise.

Alternatively, four sets of 75 ohm resistors and 100 uF capacitors in the console can be removed and replaced with jumper links, allowing for the use of regular SMS RGB cables. Capacitors C41 through C43 and C45, and resistors R41 through R43 and R45 must be removed, then jumper links can be added so the output pins on the CXA1145 go directly to the DIN connector. The jumpers must be connected as shown in the photo below; do not remove C44 and R44 as those are for composite video. Note that the solder pads for these components are very fragile, so great care must be taken when desoldering these components.

[jd213]

Yeah, I wouldn't want to mod the console itself.

This guy makes pretty good cables, he could probably make you a MK-2000 cable:
https://x.com/misirajeduart

[vol.2]

Thanks for your input.

Here’s the info that got me worried about its RGB:

https://consolemods.org/wiki/Master_Sys ... tput_Notes

I actually disagree with the above. I would absolutely 100% just mod the console. Removing three caps and three resistors is super easy and completely reversible.

Additionally, I would replace the CXA1145 RGB IC with a CXA2075, as that will give you much better quality video in general. The CXA2075 was specifically designed as a drop-in replacement for the CXA1145 that is the same but with less added noise in the video signal, and it also allows for bypassing of some previously required external components. See this page and do more searches for more info:

https://www.retrosix.wiki/cxa2075-upgrade-cxa1145

[jd213]

Ah, interesting. Might try adding a CXA2075 to one of my VA0 or VA1 Mega Drives to see if it improves the picture. (my above comment was more intended from the POV of the OP, who I assume mostly just wants to get RGB output and isn't a modder themselves)

[vol.2]

my above comment was more intended from the POV of the OP, who I assume mostly just wants to get RGB output and isn't a modder themselves

Yeah, I suppose if OP is allergic to working on electronics, then they should skip it. For all others who dabble, it's nbd.

[jd213]

On the topic of the CXA2075, it seems that only the surface-mount CXA2075M is commonly available nowadays, so replacing the CXA1145 in a MK-2000 or Genesis/MD1 would require some extra wiring or an adapter like this (this one is for Amiga, not sure if it will work on a Sega console as-is):
https://oshpark.com/shared_projects/FuaQODGP
Might still give it a try sometime though.

[vol.2]

On the topic of the CXA2075, it seems that only the surface-mount CXA2075M is commonly available nowadays, so replacing the CXA1145 in a MK-2000 or Genesis/MD1 would require some extra wiring or an adapter like this (this one is for Amiga, not sure if it will work on a Sega console as-is):
https://oshpark.com/shared_projects/FuaQODGP
Might still give it a try sometime though.

Yeah. I have a bunch of the surface mount variety and that's what I've used. It is still possible to find the through hole variant on ebay though. Just keep a search saved and it'll eventually come up.

[zinger]

Update: went for the one from Otaku’s Store. Works great (except for the jailbars, but that was expected)!