2.5" -> 3.5" SCSI adapter

Branchus

Tinker Different Public Relations Liaison 2023
Staff member
Founder
Sep 2, 2021
220
476
63
Does anyone know if a 2.5" to 3.5" adapter exists that would allow me to connect a PowerBook SCSI drive to a desktop vintage Mac?

I would hope the process isn't too complicated.

Thanks in advance,
Bruce
 
Last edited:

max1zzz

Moderator
Staff member
Sep 23, 2021
233
567
93
27
They do, I have one around here somewhere

It'll probably be quite difficult to source one now, given they would have been pretty niche even back in the day and 2.5" scsi drives are all but extinct now
It wouldn't be too difficult to reproduce though given it's just a straight through passive adapter

If your really desperate your welcome to mind if I can find where the damn thing is (Not sure waht shipping form the UK to Australia would be though!)
 

Branchus

Tinker Different Public Relations Liaison 2023
Staff member
Founder
Sep 2, 2021
220
476
63
They do, I have one around here somewhere

It'll probably be quite difficult to source one now, given they would have been pretty niche even back in the day and 2.5" scsi drives are all but extinct now
It wouldn't be too difficult to reproduce though given it's just a straight through passive adapter

If your really desperate your welcome to mind if I can find where the damn thing is (Not sure waht shipping form the UK to Australia would be though!)
At the very least I'd love to see some good quality photos of it to see if I can make my own.

Many thanks,
Bruce
 

Branchus

Tinker Different Public Relations Liaison 2023
Staff member
Founder
Sep 2, 2021
220
476
63
Here you go, this is the design I came up with for converting internal 50 pin SCSI to something a 2.5 inch powerbook drive can plug into.
Thanks so much @Androda, this is all kinds of awesome!
 

Branchus

Tinker Different Public Relations Liaison 2023
Staff member
Founder
Sep 2, 2021
220
476
63
Thank you once again @Androda! The PCB arrived today, I put it together and it's exactly what I was after. I decided to attach a whip cable with a Molex connector instead of the Berg as it suits my needs better.
 

Attachments

  • IMG_8476.JPG
    IMG_8476.JPG
    1.3 MB · Views: 162

trag

Tinkerer
Oct 25, 2021
280
133
43
I'm a little late to the party, but I picked up one of these earlier in the year and it works as advertised. Not as much geek cred as building a PCB yourself, of course.


I just bought one of those. I saw an article that linked to the seller somewhere.

The thing that puzzles me is that the 2.5" connector is 50 pins. Isn't the connector/cable on the 2.5" drive 40 pins?

Does the adapter cover the SCSI ID pins and then move that functionality to the jumpers on the adapter?

Does anyone have a datasheet for a 2.5" narrow SCSI drive? Or an old dead one they don't want any more? I want the physical dimensions.
 

This Does Not Compute

Administrator
Staff member
Oct 27, 2021
288
432
63
www.youtube.com
I just bought one of those. I saw an article that linked to the seller somewhere.

The thing that puzzles me is that the 2.5" connector is 50 pins. Isn't the connector/cable on the 2.5" drive 40 pins?

Does the adapter cover the SCSI ID pins and then move that functionality to the jumpers on the adapter?

Does anyone have a datasheet for a 2.5" narrow SCSI drive? Or an old dead one they don't want any more? I want the physical dimensions.
The adapter provides power to the 2.5" drive, and does indeed "move" the SCSI ID jumpers to the adapter's PCB. Here's a shot of the adapter connected to a drive; the SCSI jumpers are on the right and the power input is on the left.

scsi-adapter.jpg
 
  • Like
Reactions: Branchus

Androda

TinkerDifferent Board Secretary 2023
Staff member
Sep 25, 2021
499
533
93
USA, Western
androda.work
SCSI only "needs" 19 pins. 18 for data and control lines, plus termination power. The 50 pin scsi connector is mostly ground lines.

The 40 pin powerbook scsi connector has three power sources: motor power, drive logic power, and termination power. That's 5 pins used, leaving 34 (one pin missing to ensure orientation) for a pretty even split between 18 necessary scsi signals and grounds.
 
  • Like
Reactions: Branchus

alxlab

Active Tinkerer
Sep 23, 2021
287
312
63
www.alxlab.com
Here's another 2.5" to 3.5" adapter that was created back in in the day:
IMG_20211029_010952.jpg
IMG_20211029_011027.jpg


These came with 2.5" IDE to 2.5" SCSI adapters as well. The model is Winstation Systems 25HD-02:
IMG_20211029_011723.jpg


Was planning to use it in my LC 520 but then I found out the hard drive connector of the LC didn't fit in the adapter. It's on my todo list to make another adapter that will work.
 

Branchus

Tinker Different Public Relations Liaison 2023
Staff member
Founder
Sep 2, 2021
220
476
63
I'm a little late to the party, but I picked up one of these earlier in the year and it works as advertised. Not as much geek cred as building a PCB yourself, of course.

With the benefit of hindsight, a little adapter like this would have been perfect, but having gone down the path of assembling my own, I do quite like having the ability to connect two drives to the one adapter.