Media test issue
I just received my ACCURITE AAD 5.25 disk, model 206-34.  Thanks for the suggestion.

Because I am attempting alignment for the first time, before I screw anything up let me confirm a few things and ask some questions:

- I don't want to insert this disk into a drive with a bad head, for fear of scratching it.  It is recommended therefore to test the drive first with an expendable disk.  What evidence disqualifies a head?  Scratches?  Anything else?

- I haven't seen a listing of the disk's contents; there's nothing on the label except alignment data, and I haven't stuck the disk into a drive and entered DIR, but I don't think there's an exerciser program included with this disk.  Instead I can use Dunfield's ImageDisk program with the Align/Test option selected.  Is there any other program suitable to the task?

- I want to avoid using any OS but plain old DOS for this exercise because I have heard, anecdotally, that the later Microsoft OS versions take the liberty of writing info to the disk, which Accurite warns against.

-Is there any value to creating an .scp image before doing anything else with the disk?  I think to have any value the SCP image would have to be written back using the same unaltered drive, but I'm not sure that would be accurate enough for future use.

- I have a scope and I have some technical / repair data for some manufacturers; TEAC and Tandon, for example.  But I have Chinon, Fujitsu and Panasonic drives as well. I will need to know where to ground and where to probe while looking for alignment signals.   Is there a repository of tech information somewhere that I could reference?

Thanks for any suggestions.


PS: I now have a load of Atari ST programs on 3.5 inch disk, including a copy of CopyIIST...  Did you work on that title?
Take a blank disk that has no scratches on it (circular scratches) and insert it into your drive and make an image. During the imaging process, the disk you should pretty quiet. If you hear a loud "wooshing" sound, especially if it oscillates, then some loose particles are on the head and/or disk. Remove the disk and check for scratches. I recommend frequently clean the head with a cotton swab and 90% alcohol. If you don't see any scratches on the surface of the disk (either side), then you are probably pretty safe.

I don't think there are any "contents" on the AAD disk. These are special analog tracks, and not contain any data that can be retrieved (as far as I know).

You don't use the drive for anything more than spinning the disk and stepping the head. You need to use a dual channel scope to read the analog signal from the head to determine the track alignment.

There is no need to make an image, you can't.

I don't have information on these drives, but Sncboom2K (user here) might.

No, I didn't work on the Copy II ST program, but his office was next to mine. That guy was hysterical! He coded to head banger music cranked up!
"You need to use a dual channel scope to read the analog signal from the head to determine the track alignment."

Got a Siglent SDS 1102 CNL digital storage scope, 100 MHz, dual channel, specifically for this purpose.  My other scope is an old Leader LBO 502, analog, 15 MHz, single channel; wasn't going to do the job.

That is similar to my Rigol scope. That should work well.

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