If your 720kB floppies have been stored reasonably well (I've kept most of my tapes and floppies in the office for decades now, seems good enough), you should be ok unless you were unlucky with the floppy vendor. Make sure you get a drive that can read 720kB though.. not all USB drives can do that. I bought a TEAC FD 05-PUW (IIRC) which also reads 720kB, a couple of years back.

At page four, I don't know if anyone still finds this interesting, but the FCC RF emission rules were changed during Apple ][+ production, and before the /// and //e.

I have one of the Apple ][+s that was an "RFI model" (at least that's what some of us called them). There were Apple ][s like this, too, as production was concurrent. What it is, is a standard ][ with some kludgy added in shielding. It consisted of some tin and braided strap stapled to the plastic case. I removed all of this from mine, else I could show pictures. I removed it because it wasn't very effective anyway, and, it caused the cover to not fit properly.

The /// has silly amounts of aluminum the way the Ataris apparently have silly amounts of steel. By the time they designed the //e, they figured it out. The inside of the plastic parts of the case are coated with Aquadag, and bonded to the sheet aluminum case bottom.

I sure would love to have one the the ///'s.

I have a Tandy 1000 EX that has crazy shielding too. Inside, there is a blanket of foil that is thick and flexible. The bottom is covered in something non-conductive because it sits directly on the PCB. It's neat and annoying at the same time. When you open the case the only thing you can see is one little port connector. You have to take out all of those blankets.

I guess they did it this way because that machine is so compact...well, for the time I guess.

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Cat; the other white meat.

I suppose that between the inventory of existing boards and the expense of doing a multilayer board back then (to get a ground plane layer inside), adding the case shielding was a cheaper solution.

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

A quick followup. Today I finally got my hands on a USB floppy drive (through Amazon from a manufacturer called HDE). Curiously Windows 10 didn't understand my Atari ST disks, claiming them as unformatted. Attaching to a VMWare VM running Fedora Linux (where I run Hatari - my Atari ST emulator), the disks read just fine. It was fun to see my old 68k code from '86. I even assembled and ran a few proto games. Nostalgiagasm ensued.

I just wanted to thank you for your advice w.r.t being careful to choose a drive that supports 720kB disks. This drive reports as a TEAC (whether or not it is I suppose doesn't matter), but I was very careful to select from only drives that claimed support for 720kB and then I read the Amazon reviews for indications that they'd actually work.

I'm sure it wouldn't have occurred to me that some drives couldn't read 720kB formatted disks. So, thanks Tor, and thanks to others for encouraging me to try to read from these old disks. I almost couldn't believe there's be valid data there.

You're welcome! I was just passing on information I got from somebody else back when I needed a floppy drive - I too wasn't aware of the many limitations of USB floppy drives, at the time.

Nuts... I spoke too soon. The USB floppy drive is presenting my disks as having 1440 sectors (2 sides x 80 tracks x 9 sectors per track). Many of my disks were formatted with 10 sectors per track. The extra sector isn't accessible

Ahh.. the problem with USB floppy drives, and which is why some only support 1.44MB in the first place, is that they're not true low-level floppy drives like a drive connected to a proper floppy controller. Well, the drive inside may be, but that USB interface is a high-level interface pre-programmed to handle certain formats. So they'll 'understand' only 1.44MB 'IBM' format, and for the TEAC drives and some others, also the 720KB 'IBM' format - which is 9 sectors per track. In that sense they're as limited as unmodified Gotek floppy emulators.

That's how I understand it anyway. It's a pity that a USB floppy drive can't really replace an old-style floppy drive.

In this case I would recommend getting a Kryoflux and an old-style 3.5" floppy drive (which can alternatively also be bought from the Kryoflux guys - they have drives that have been properly re-aligned and tested. Except that I see that they currently don't have them available in the store. But any drive can be used, if you trust it to be reasonably ok).

Adrian received a beautiful Atari 800 with a dead main keyboard, and he's fearlessly going in deep! That custom chassis looks amazing!

https://www.youtube.com/watch?v=-X-IMg5yMQA

(I haven't even finished watching the video yet, but I paused it to add to this thread I remembered).

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Got a kilobyte lying fallow in your 65xx's memory map? Sprinkle some VTL02C on it and see how it grows on you!

Mike B. (about me) (learning how to github)

I was flabbergasted by all that cast metal, but then I remembered that the FCC interference rules used to be much tighter.