24 May
2001
24 May
'01
7:19 a.m.
On May 24, Jonathan Engdahl wrote:
It looks like what you have here is 1/2 of an SDI
adapter.
Yup.
Now the next question: what is SDI? I'll assume
for now that is was an early
approximation to SCSI, something proprietary to DEC.
It has *nothing* to do with SCSI. SDI is a relatively
high-performance (amazing for its day) high-level command-based
interface that is used to connect to DEC RA-seris drives. It uses
small cables that contain four pieces of 1/8" coaxial cable that
terminate in an 8-pin Berg-like connector.
It's useless without the other board, and they're both useless if
you don't want to run RA-series disks. Contrary to popular belief,
not all RA-series disks are huge (14" platters) and power hungry. I
have a stack of 1GB 5.25" RA73 disks that are rather nice.
-Dave McGuire