The [[AD1 ROM Cartridge]] from [[Arnor]] is a miniature ROM board that accepts only one single ROM/EPROM chip. It was (optionally) shipped togther with Arnor ROM software (namely with [[MAXAM]] and [[Protext]]; maybe it was also used for other ROMs).
The purpose was to motivate people to buy ROM software, without forcing them to purchase more expensive multi-socket ROM boards.
There is also an AD2 version, which is expandable to hold 4 ROMs.
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Image:ACU8506-058.jpg|Review (ACU June 1985)
Image:ACU8506-062.jpg|Coupon (ACU June 1985)
Image:File:ACU8512-134.jpg|Protext Cartridge Review (ACU Dec 1985)
Image:ACU8512-022.jpg|Protext/Maxam AD2 Advert (ACU Dec 1985)
</gallery>