C128 Guy
Experienced Member
Looking to buy some 5.25 quad density disks. Anyone have some kicking around?
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Ontario Looking for Quad Density Disks
- Thread starter C128 Guy
- Start date
Ontario
Chuck(G)
25k Member
As far as I have been aware of using QD drives for about 45+ years, QD and DD media are the same, but with different labels. The manufacturer may have verified at 96 tpi vs. 48 tpi but the goo on the cookie is still the same. FWIW, I may even have a few disks with "100 tpi" manufacturer verification. It doesn't matter.
C128 Guy
Experienced Member
I used to get away with using better quality disks DD in QD drives, but with media getting older I'm struggling to find ones that will work. If you have ones labeled 100tpi I'd buy them from you to try!
Chuck(G)
25k Member
100 tpi disks are going to be very old indeed and probably be worse than anything you have. You're better off finding quality DD floppies. 3M/Imation has been very dependable, as has Dysan.
I'm reminded of a conversation I had with a customer engineer at Verbatim, before they moved their facilities offshore. Verbatim offered two basic lines--the "pink label" and the "purple label" floppies. I asked what the practical difference was. He responded that basically, the pink label floppies were garbage.
When personal computing got to be mainstream, there were a lot of off-brand floppies around. Brown Disk, Elephant, etc. All were pretty much terrible. Wabash was singularly awful, often shedding right out of the box (their 1/2" mag tape aged ungracefully as well). Control Data 5.25" disks were nothing to brag about either. There were budget "second line disks", like "Precision" which were made by Xidex.
Get a NOS box of floppies, bake them at 58C for about a day. That should solve a lot of binder issues.
I'm reminded of a conversation I had with a customer engineer at Verbatim, before they moved their facilities offshore. Verbatim offered two basic lines--the "pink label" and the "purple label" floppies. I asked what the practical difference was. He responded that basically, the pink label floppies were garbage.
When personal computing got to be mainstream, there were a lot of off-brand floppies around. Brown Disk, Elephant, etc. All were pretty much terrible. Wabash was singularly awful, often shedding right out of the box (their 1/2" mag tape aged ungracefully as well). Control Data 5.25" disks were nothing to brag about either. There were budget "second line disks", like "Precision" which were made by Xidex.
Get a NOS box of floppies, bake them at 58C for about a day. That should solve a lot of binder issues.
C128 Guy
Experienced Member
Any particular brands you would recommend?
Chuck(G)
25k Member
3M/Imation would be at the top of my list.
Bruce Tomlin
Experienced Member
It's going to be the magnetic properties of the media that are most important. It's like regular vs chrome cassette tape. High Density disks need a stronger magnetic field to write, and that's why you don't want to mix them up with "regular" disks, either way.
So-called "quad density" is apparently just 96tpi instead of 48tpi. It's just a marketing term. I was using 80 tracks on a TRS-80 before anyone called it that. That is a much less demanding dimension of density than the individual bits in a track. Just get some good DSDD disks and you'll be fine.
As far as disks being garbage, I never really had any problem with 5 1/4" disks. It was HD 3.5" disks in the 90s that gave me so much trouble. I think it was more due to disks being made in bulk quantity with less care for quality.
So-called "quad density" is apparently just 96tpi instead of 48tpi. It's just a marketing term. I was using 80 tracks on a TRS-80 before anyone called it that. That is a much less demanding dimension of density than the individual bits in a track. Just get some good DSDD disks and you'll be fine.
As far as disks being garbage, I never really had any problem with 5 1/4" disks. It was HD 3.5" disks in the 90s that gave me so much trouble. I think it was more due to disks being made in bulk quantity with less care for quality.
krebizfan
Veteran Member
With standard cassettes, it was possible to have a dropout that only affected one channel in stereo but had no effect with a mono recording. I could see something similar happening with 80-track formats where the holiday in the coating is too small to impact 40 track formats.