Manufacturing, Remarking, and Forgery
Since 6581 and 8580 SID ICs are no longer produced, they have become highly sought after. In late 2007, various defective started appearing on eBay as supposedly "new" chips. All of these remarked SIDs have a defective filter, but some also have defective channels/noise generators, and some are completely dead. The remarked chips are assumed to either be factory rejects from back when the chip was still produced, or possibly 'reject culls' from one of the chip pulling operations which were used to supply the chips used in the Elektron SIDStation and the HardSID cards. Fake SID chips have also been supplied to unwitting buyers from unscrupulous manufacturers in China; the supplied chips are laser-etched with completely bogus markings, and the chip inside the package is not a SID at all.
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