20SC Hard Disk

[pierofirenze]

Good morning to everybody,

I have found a very nice Macintosh Plus computer complete with its external Hard Disk 20SC that is probably not working. This is the reason why I am here...

I would like to ask if anyone know the functionality of this drive. When I switch on the Hard Disk the red led on it will ligth five times, then, if I will switch on the computer the 20SC led will blink again other five times and then it will blink continuosly very shortly, it seems that the the computer is trying to read the HD but it does not work.

Does anyboy know what is happaening? And perhaps how to fix the problem?

Thanks in advance

 

[olePigeon]

Hard to tell.  Does anything else happen?  Does it come up with a disk and a flashing question mark?

It may be salvageable if you can make a Disk Tools disk to check the disk.

 

[pierofirenze]

Hello, thanks for your answer.

The Macintosh is working, it asks for the booting disk and i can load the OS from Floppy. I also have a Floppy Disk with HD setup application. When I run this application it says "No suitable Hard Disk found on the SCSI"

 

[BadGoldEagle]

You own a SCSI terminator, right? Otherwise it won't work.

I had a HD40SC that wouldn't work with my Plus. It seemed all right, made the right noises, the LED did blink and all but I didn't know about SCSI termination back then. Once the terminator was in place it worked like a charm!

BTW, Welcome to the 68KMLA! 

 

[olePigeon]

http://www.ebay.com/itm/BELKIN-F2N958-A-Pro-Series-SCSI-Terminator-ACTIVE-Centronics-50-Male-NEW-/381435731373

One of these should do the trick.

 

[CelGen]

I seem to recall the 20SC's were just the nasty 20mb Miniscribe drives.

 

[bibilit]

Yes most of them are Miniscribes, and most of them didn't work anymore...

 

[BadGoldEagle]

I seem to recall the 20SC's were just the nasty 20mb Miniscribe drives.

My HD40SC's a SONY

 

[Scott Baret]

I have three 20SC enclosures. One came to me with an 80MB Quantum inside. The other two had dead 20MB MiniScribes. The power supplies are pretty reliable in those boxes, so even if you get a dead MiniScribe (usually the full size variety, although it is possible to mount the smaller drives in there), keep the enclosure and put another drive inside.

 

[pierofirenze]

Hello, many thanks to everybody for the suggestions.

My Hard Disk is a Seagate St225N and apparently it should work. The termination I am using is a passive one, it is a male to female parallel adapter but it is done to be a terminator. Perhaps what I need is an active terminator. I will look to find one in Europe.

 

[olePigeon]

I'd recommend a Centronics SCSI active terminator.

 

[Bunsen]

male to female parallel adapter

As in, something that you use on a PC parallel printer port?

Don't use that if so.  SCSI and parallel ports are wired differently.