Unterminated SCSI drives?

After two decades of building computers I have about a dozen old 50 and 68 pin SCSI drives laying around. Only a couple are crashed, most got obsolete and were pulled. I have an old computer with a working LVD SCSI bus and a 68 pin port. The thought occured to me to fire up the old drives and see if anything interesting was on them, the trouble is most of the terminators went astray years ago. If I plug in a drive without a terminator is it likely to work or would I be wasting my time?

I actually did this back in the day. A single device usually works better than multi devices for this. But note that there’s a lot of “self-terminating” things so check to see what you have in that department. (Sometimes a jumper setting.)

As a bit of trivia I never built a computer with standard IDE drives for myself. I started with Fast SCSI and eventually worked my way up to a pair of 10K Cheetah drives on a Ultra2 Wide bus, those things when turned off sounded cool, like a jet engine spinning down. I switched directly to SATA when the Raptors came out (I eventually got the one with the clear top), and now am running SSDs.

Termination is basically preventing reflections on the signals. I haven’t written a SCSI driver since the late 90s, but I seem to remember lots of problems without termination.

As ftg mentions, some drives can self-terminate. There was sometimes a jumper you could set.
I think the jumper sets had little coded documentation next to them…or you can find notes online.

Keep in mind that “single ended” and “differential” drives don’t co-exist. You likely only have one type - you mention LVD. I thought most old PCs used single ended, and higher tier stuff used differential.

-D/a

I don’t know about LVD, but SCSI terminators are still pretty cheap for external drives depending on whether or not you get the passive or active variety and depending on the width.

I had mainly 50pin SCSI peripherals in external cases and used these extensively. My adapter card needed termination on the internal or external side if there were no drives on that side and there were jumper settings for that.

Internal drives normally had a jumper setting for termination.

I’ve got a bunch of old Macs that I’ve had for years, and have swapped drives in and out of repeatedly. If I’ve got a terminator handy, I use it, if not, I don’t. Without termination, usually it works, sometimes it doesn’t, with no rhyme nor reason. Try it. You’ve got nothing to lose, since they don’t die if it doesn’t work, without termination.

Hmm I have a bunch of old Mac internal scsi drives I’d love to get content off of. How do I connect them to my new Mac?

As far as I know, you can’t. The new ones use IDE instead of SCSI.

You can buy a SCSI-to-USB adapter, but they aren’t cheap. In fact NewEgg at the moment doesn’t have any (but they have two that are marked as out-of-stock. I’m guessing the demand on this item isn’t high.) EDIT: amazon carries some

Also keep in mind your old drive is probably HFS. I’m not sure if OS X can read that format-- it uses HFS+ and Apple ain’t exactly the best at backwards-compatibility.