Category Archives: Modification


NEC PC-9821 and the Framemeister

The NEC PC-9821 computers output a very unusual resolution that most western monitors struggle with: 640 x 400 @ 24 kHz. I tried at least half a dozen monitors of all types and ages and none of them was able to display a picture at all (except an “out of range” message). Video scalers like the DVDO iScan VP50 Pro don’t recognize the signal either. Some sources claim that the cheap GBS-8220 converter is able to convert the signal – that is only partially true. You can see a stuttering picture that eventually becomes clear when you start the Windows 98 Desktop, but that doesn’t work in DOS.

Of course you can buy a special converter like the Micomsoft XPC-4, that will cost you 300-400€ though. There are other solutions:
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Atari Jaguar Power/Sound Fix and Rotary Controller

The other day I prepared my Atari Jaguar to build a rotary controller for Tempest 2000. I hadn’t used it in a while and accidentally picked the wrong power supply – smoke was rising from the console immediately.

The culprit was easily found, chip U38 (MC34163DW):

Toasted U38 (MC34163DW)
Toasted U38 (MC34163DW)

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A new battery for the Sega CD BackUp RAM Cart

Now that I have an extra backup of my Mega-CD save files on the Sega CD Ultra Backup RAM cart I can replace the battery of my the old CD BackUp RAM Cart without worrying about data loss.
It is possible to do an open heart surgery to prevent the memory from being erased and replace the battery while the Mega-CD is turned on . I went for that procedure to avoid having to copy all files from one cart to another again.
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WS Flash Masta and Neo Pocket FlashMasta / LinkMasta

Two days ago Flavor of anounced the pre-presale of a new WonderSwan flash cart: The WS Flash Masta.
For all Bandai WonderSwan owners this is exiting news as the flash/development carts for this system are very rare and expensive (e.g. the official WonderWitch or the WonderMagic Color).

To give you an idea what we can expect I’ll show you some carts he has made for the Neo Geo Pocket Color:
First there was the Neo Pocket FlashMasta and the Neo Pocket LinkMasta. I’ve used the Blue Version of the LinkMasta since 2011 and bought a new red 3D printed case for it last year.

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Sega Pico Flash Cart Tutorial

This has been figured out and posted by TeamEurope in 2012 (link, link via link). Unfortunately, the original document has vanished from the WWW. I’ll try to recreate this tutorial here:

The original document suggested to use Sesame Street: Alphabet Avenue as donor cart and pointed out to use an „Assembled in Mexico“ cartridge. As you can see, a regular US cartridge won’t do the trick.
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