Thank you. I haven't heard from Brett Glass in decades, since he moved to Idaho. He ran the numbers and decided that the differential in market value between his housing here and similar in Idaho was enough to support him for quite a while. Since he was working as a writer, he didn't have to be physically close to his work, and he could get decent internet access through the university there. 3" drives were readily available in MFM compatible forms. The drive was designed to be a drop-in replacement for 5.25" SA400 style drives. (OK, "SA450"?). And the 3" drives even used a 34 pin card edge and a "molex" power connector (like 5.25"; unlike 3.5") Depending of format choices, MFM from 180K to 720K. Amstrad used them, as did early Gavilan and some others. The Gavilans that I had (both 8 and 16 line models) were later ones, with 3.5" drives. Gavilan's MS-DOS 2.11 3.5" format was not the same as IBM's PC-DOS 3.20 720K format. But, some development continued, even after Gavilan collapsed, and the Gavilan MS-DOS 2.ll version K was the same format as IBM. For those not familiar, MS-DOS 2.11 and 3.31 were versions that were heavily modified by OEMs, particularly for drive types (including >32M in 3.31). Hence, 2.11 and 3.31 are DIFFERENT from one OEM to another! But, early on, AMDISK marketed two drive external boxes for Radio Shack Color Computer and for Apple2. Coco was box standard SA400 compatible drives. I never had one of the Apple2 3" boxes. So, I have questions about the interface. Q: Was it a different logic board on the 3" drive for compatability with the Apple2 "DISK2" interface? (GCR encoding) Q: Or did their external 2 drive box come with its own MFM FDC for the Apple2? (In which case, like the SVA FDC, it could adapt an Apple2 to "standard" drive types) I assume that the 2 drive external boxes came after the original drive as 5.25" drop-in retrofit, but I could easily be wrong, and it is POSSIBLE that the Apple2 version could have been the first release of the drives. The 3" drives were available in 40 and 80 cylinder models. The 3" drives were available in single and double sided. The single sided drives would permit "flippy" operation, to use the other side of the disk as if it were another disk. BUT, the double sided drives (at least the few that I had) would NOT let you insert a flipped disk; therefore, the double sided drives could not access the "B" side of a "flippy" disk! I never got around to looking into modifying the drive for that. -- Grumpy Ol' Fred cisin at xenosoft.com On Sun, 1 Dec 2019, Sellam Abraham via cctalk wrote: