To me it looks like a floppy controller from a CoCo. http://cini.classiccmp.org/ Long Island S100 User’s Group Get Outlook<https://aka.ms/qtex0l> for iOS ________________________________ From: vcf-midatlantic <vcf-midatlantic-bounces@lists.vcfed.org> on behalf of Bob Shuster via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Sent: Saturday, July 16, 2022 1:41:11 PM To: vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> Cc: Bob Shuster <bob@theshusters.com> Subject: [vcf-midatlantic] TRS-80 mystery item I found a device among my TRS-80 stuff that I can’t identify. It’s some sort of floppy controller, but in a blank case. It’s got an FD1793B-02 chip socketed in it, and 40-pin and 34-pin card-edge connectors on each end. Solder side of the board has “8709203 Rev. B” on it, but I can find no reference to this online anywhere. Anyone have a clue? Photos here: https://drive.google.com/drive/folders/1M2AKhMpHAAJ7If6sKEbWejRZ9J_YFsNs?usp... <https://drive.google.com/drive/folders/1M2AKhMpHAAJ7If6sKEbWejRZ9J_YFsNs?usp=sharing> Thanks. - Bob Shuster