bkn@duke.UUCP (06/14/83)
>From unc!tucc!sdt Mon Jun 13 20:24:30 1983
Date-Sent: Mon Jun 13 19:56:33 1983
To: unc!duke!bkn
Subject: Re: duke.3285: Hard Disks for the IBM PC
I am presently "testing" the Amdek Amdisk III on my PC. The only problem
that I have found with them is that with DOS 2.0, each "diskette?" only holds
180K.......between the two units, thats only 360K! Now, where Amdek really
suckers everyone is when they say that each disk (formatted) holds 360K, they
are talking about both sides! The biggest problem with this is that in order
to use both sides, you must take out the disk, turn in over to side B, and then
reinsert the thing!!!! Now, marketing wise, they can claim that the unit (two
drives) holds 640K!!!! What they don't tell is that in order to get that, you
have to take the disks out and turn them over!!!
I have tried unsuccessfully to use JFORMAT to format each side for 200K.
Speed-wise, they are pretty much the same as Tandon's. I have had no trouble
at all out of them using DOS 2.0. Some technical specs are them are:
Unformatted capacity - 250K per surface
Formatted capacity - 180K per surface
Tranfer rate - 250K bits/second
Access time - Average 55 ms
- Track to Track 3 ms
- Settling Time 15 ms
Head Load Time - 50 ms
Motor Start Time - 1 sec.
Track density - 100 TPI
Rotational Speed - 300 RPM
Overall, the manual is written very well if you are technically oriented. They
provide all necessary interfacing diagrams. The unit comes ready to plug into
the 52-pin connector on the back of the disk drive controller card. There are
no software changes necessary to any PC-DOS software. I am having some trouble
using the drives with the UCSD p-System, though.
I would say that the unit is nice to have even though they are single-sided. If
or when Amdek or Hitachi (the drive manufactorer) make the drive double-sided,
I would say they would really have a super product.
Hope that this information will help you somehow!!!
Scott Totaro (sdt) ..... ComputerLand of Charlotte
P.S. The technical specs came directly from the Amdek "Amdisk III Information Manual".