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What blank floppy media should be used for writing RX50 format floppies?

gslick

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RX50 format is 250KHz MFM, 10 sectors per track, 512-byte sectors, 80 cylinders, 96-tpi, single sided.
800 sectors and 409,600 bytes total formatted capacity.

If RX50 format floppies are written using a PC with a TEAC FD-55GFR "1.2MB" floppy drive, for best results when the floppies are later read in a real RX50 drive should original capacity 5.25-inch floppy media be used, or should HD capacity floppy media be used?
 
This may be SLIGHTLY relevant..

Some years ago, at a former employment, they were using the DEC word processing system - I think it was DECMate. They were using 5.25" floppy disks, rather nice DEC branded ones. I was just starting to use computers, and I needed standard floppy disks. I ended up with a few of the DEC ones - I think these were disks that they had a problem with on the DEC machines, and they were throwing them away, but I 'salvaged' them. These disks worked totally perfectly for me. Never any problem with 360k format for PC or CP/M. Then I later began using DSDD disks with a 96tpi drive to format to 730k, they again worked fine. The disks were certainly normal DSDD type. I think they had a red arrow on as well. There were some that were u/s even for me, but I kept the DEC branded tyvek sleeves. Anyway, they were all certainly never HD type.

Geoff
 
I can relate a conversation I had with a Dysan tech more years ago than I care to remember. Y'all remember Dysan, right? Maker of some of the best media in the business, before they were purchased.

I've got Dysan samples labeled "100 tpi" "96 tpi" and "48 tpi". Curiosity got the best of me in the 1980s, so I asked my contact at Dysan what the difference was. His response was "the label, mostly".

I'll also add that RX50-specific floppies may be pre-formatted and usually do not have hub reinforcements. And RX-50-specifc media generally has "arrow labels" per DEC convention. But the brown goo that coats the cookies is the same.

That's not the case for DSHD media.
 
Plain old DS2D media is the stuff. Add arrows if you like.

I did use some generic non-branded non-HD media to write some RX50 format disk using a TEAC FD-55GFR and they worked well enough to boot a MicroVAX II from them in an RX50 drive.

And I did add some home made arrows to them after I figured out through trial and error which way there were supposed to go, which wasn't helped by one of the two units in the RX50 drive not being fully functional. For future reference, the correct orientation is to insert the disks with the label side facing away from the center of the drive.

First time trying to use an RX50 drive. I haven't looked at one close enough to see how easy or difficult it might by to try cleaning the heads and see if that helps the unit that isn't working. I don't have any head cleaning disks, I've never had or ever used any of those.
 
You can get away with writing RX50 (and for that matter, PC 360KB) data to unformatted{/b] DSHD. Indeed, I've received Kaypro II disks that were written to DSHD media.

It's still not a good idea. You really do want saturation-level recording.
 
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