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  • Joined: 11 Dec 2019
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Modded Master System 2's and Genesis/Megadrive 1/2's for sale
Post Posted: Wed Dec 11, 2019 10:26 pm
Last edited by retroleah on Fri Aug 28, 2020 8:17 am; edited 1 time in total
EDIT: UPDATED jailbar fix for SMS2 on this page:

Hi everyone :)

EDIT BEFORE SUBMIT: I discovered that new members can't post links, as a counter-measure to spam. However, I assure you that I wish to be a productive and contributing member of this forum. Since this section is for selling sega systems, I feel confident that I'm not violating any rules... my website selling these modded sega consoles is

I just signed up here so this is my first post. My name is Leah Rowe and I am the founder of RetroFreedom which sells Sega consoles that are heavily modified by me. You can read all about the company here: redacted and about my setup (for soldering with) here:

For sale are the following systems, heavily modified to be region-free with 50/60hz switches and a *ton* of other mods you won't find pre-installed else where (I really go the extra mile)...

Master System 2:

Genesis/Megadrive 1:

Genesis/Megadrive 2:

I am a passionate retrogamer. My first console (when I was 4) was a Sega Master System II. Over the last year, I've been studying the hardware of various consoles including Sega ones. This includes reading the schematics and analysing traces/signals/components on each board. I've amassed a great wealth of knowledge and I am now proud to announce that I am selling these old systems, fully refurbished.

In general (not taking into account the extensive modifications that I do), I refurbish and clean these systems. I replace *all* electrolytic capacitors on the boards, even if they all work fine (as a preventive measure, since these old caps can and do fail sooner than you think). If traces are damaged (e.g. from leaking capacitors) I clean the area and re-establish the circuitry. I'm quite handy with soldering and I use high-end equipment.

I can also damage repair done by other modders... or you can send you stock console to me and I'll mod it for you :)

I heavily modify the systems, as follows:

* RGB mods done to Master System II (to DIN8 socket). clean CSYNC is used, though Composite Video is also routed to the DIN but on its own pin.
* Jailbar fixes on SMS2: re-route Z80 clock and colorburst clock so that these signals don't run alongside RGB lines (also partially re-route the RGB lines: cut VDP pins and run wires from them to the 820ohm resistors on-board as usual - this seems pointless to some, but it reduces the amount of noise from the board going into the signal, since otherwise by default that area they're routed in is quite noise (see pics below)
* colorburst selection on SMS2, for PAL or NTSC (TODO: I will in future also throw in an extra 4.43mhz oscillator for customers who wish to use PAL60 on 60hz composite video)
* 50/60Hz switches on SMS2 (also megadrive). double-pole double-throw switch also used which provides the correct 53.2mhz master clock for PAL, or 53.69mhz for NTSC mode. I currently switch the crystals on the switch but I'm looking into doing it this way instead: make the switch auto-set the colorburst and have an analog switching IC e.g. 4066 detect whether VDP is in PAL or NTSC mode via PAL/NTSC select pin, and route the clock output according to this.
* SMS2 pause button is re-wired for reset. The joypad's TH line is mapped to pause instead. I provide joypads wired for SMS2 with pause buttons on them that do indeed work as the original pause button on the console does.
* RGB bypass mod (voultar board) on Genesis/Megadrive model 1
* M1 Mini Mega mod (audio bypass) on Genesis/Megadrive model 1
* OR: dbElectronics "Triple Bypass" on Genesis/Megadrive model 2, which bypasses RGB and audio

The RGB bypass mod greatly improves picture quality on RGB, reducing jailbairs. The M1 Mini Mega (or audio op-amp on Triple Bypass) greatly cleans up the audio, creating crystal clear sound output

If you want to buy a system from me, DM on twitter (my user is n4of7) as I probably won't change private messages here (it's been a few years since i've been to a forum!)


Here are a few example pics of my work! (pics of modded SMS2 and MD1)
md1_bypass.jpg (280.96 KB)
md1_bypass2.jpg (274 KB)
md1_crystal.jpg (242.63 KB)
md1_ps2.jpg (260.69 KB)
md1_switches.jpg (258.37 KB)
sms2_board.jpg (307.18 KB)
sms2_led.jpg (153.78 KB)
sms2_rainbow.jpg (155.67 KB)
sms2_switches1.jpg (183.02 KB)
sms2_switches2.jpg (179.81 KB)

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Post Posted: Thu Dec 12, 2019 7:29 am
Links added above.
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Post Posted: Tue Jun 30, 2020 6:39 am
How are you getting the image on the LCD? Is this using a transcoder / upscaler ? I haven’t really had issues with jailbars on my PAL consoles. Master system or megadrive ... sort of wonder why people go to so much effort with the RGB bypasses etc.

Same with the SNES. Lots of work and almost no difference according to forums
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Post Posted: Fri Aug 28, 2020 8:47 am
Yeah I use an OSSC to do that.

OSSC converts analog RGB to HDMI, and it lets you tweak a lot of parameters.

These pictures are out of date. I do MUCH better work these days! Also see link in first post: I've edited it to link to a newer thread regarding SMS2 jailbar fix.
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