Sunday 30 December 2018

Sega Master System II Composite Video Mod

This is an old post, preserved for reference.
The products and services mentioned within are no longer available.

In a recent video, ChinnyVision reviewed the Sega Master System, and was very scathing about the Sega Master System II.
The main reason (other that the 90s rounded styling), is the only video output on the SMS II is RF.
The original Sega Master System with it's 80s angular design not only looked better.
But had an RGB output connector.
All that is required to get a good picture out of these is and RGB SCART cable (as ever, I just got one from Retro Computer Shack as their stuff always seems to work).
So is there anything that can be done for the SMS II?
Under the rusty shield, is quite a small board (SMS Portable anyone?)
Good to see a real Zilog Z80 in the top right.
In the middle, is the same video output chip as the SMS, so if you don't mind hacking up the case a bit, you could install a DIN video output socket wired the same as the SMS.
However, an easier option to get an improvement over the RF output is to remove the RF modulator and install a composite video output.
Although that's easier said than done as the tabs on the modulator were folded over before soldering..
That leaves space to fit the 'Deluxe Composite Video Mod' from The Future Was 8 bit.
I've put the board back in the case to align the socket with the hole used by the RF modulator.
That should line up nicely to avoid any modifications to the case. The four pole 3.5mm jack is connected to three phono plugs, two audio (wired in parallel) and one composite video, so that's all in the one connection fitting neatly in the existing hole.
With that fixed in place with a foam pad, it's just a case of wiring it up, and there's not much to that.
The black wire is soldered in to one of the holes where the tabs from the modulator went through the board (which is where the modulator got it's 0V connection). The red, white and yellow connect to the 3 pin header, not the order is not the same.
The best position for the board is slightly overhanging the edge of the PCB, so the socket is close to the edge of the case.
Reassembling that, all looks good, and with the case back on, and the cables plugged in, it looks like it was designed like that.
The SMS II has a built in game, Alex Kidd in Miracle World.
But, I think it's time for some Sonic, and that's looking good.
Zooming in on the screen, you can see a difference between composite....
.... and RGB.
It depends on your TV / monitor, but the composite version is still better picture than RF (if you can get the RF to tune in on a modern TV these days).
So if you fancy a bit of Master System, and the prices of the original SMS are a bit high, then a composite mod on an SMS II is a reasonable alternative.