3.5" drive mods

[JohnBuell]

I've seen the kits, I even saw a modded XF551 on eBay recently...

 

But does anyone actually still SELL the kits, or do the modifications?

 

Just curious.

[fibrewire]

No kit necessary - just follow the instructions.

 

http://blog.3b2.sk/i...-XF551-2_3.aspx

 

For the record, 5.25 floppies are much more robust when it comes to shelf life & usability. In the late 1980's - when 3.5 was replacing 5.25 in the PC market - the conversion made sense because 3.5 drives and media were cheap and readily available, 5.25 was not.

 

Today, replacing 5.25 mech with 3.5 means breaking compatibility with the standard Atari 8-bit format. Any benefit of moving to 3.5 has been lost, and even SIO2PC has replaced the 5.25 floppy as "the standard" Atari 8-bit format.

[MEtalGuy66]

5.25" single sided floppys will alwayse be "the standard"..

 

"The convention" these days is to emulate floppies using SIO2xxx devices instead.

 

In the late 80s, you couldn't GIVE AWAY all the 5.25" PC drive mechs that were floating around.. in fact right up until the late 90s, people were just throwing them away because they werent worth the space it took to store them. Millions of them were being jerked out of PCs and legacy equipment, and replaced with 3.5" drives (or even more modern removable storage types).

 

The reason XF551 3.5" floppy upgrades made sense in the late 80s & early 90s was that hardisk setups (or any mass storage type setup) for an Atari 8-bit still costed an "arm and a leg" so to speak. a 3.5" floppy drive mech was significantly cheaper, and 720k holds ALOT of stuff on an 8-bit machine, relatively speaking.

 

What you really should know is this: 1.44meg HD 3.5" media is crap.. 1.44meg HD drives, operating as 720k drives are less than preferable (they write tracks too narrow, and are thus less reliable and more allignment-critical, especially when exchanging floppies between drives)..

 

If you're gonna do a 3.5" upgrade on an XF551, you really need to find a REAL 720K (3.5" DSDD, NOT HD) drive mech. These things are priced INSANELY HIGH nowadayze..

 

So basically, you should leave your XF551 5.25" the way it is... If you want a decent upgrade, get someone to burn you a "HyperXF A" EPROM to replace it's firmware (fix all the bugs and add true ultraspeed).

[+Larry]

I can't get very excited about real "floppy" disks these days -- images are sooo handy.

 

Perhaps you are thinking about the track width differences between regular 5-1/4" disks and 5-1/4" HD? Track widths on 720K (3.5") and 1.44 MB (3.5") are the same. Or at least all the PC texts I've read say that they are.

 

http://www.freeopenbook.com/upgrading-repairing-pc/ch11lev1sec4.html

 

The difference is the sectors per track and of course, the magnetic media and write current used. Even the Floppy Board went from 18 sectors per track to 36 sectors per track for HD (and it was still not terribly reliable in 1.44 mode).

 

My take: As cheaper and cheaper 3-1/2" drives made their way into use, the performance & reliability got worse and worse. I used (early) Sony drives in both 720K and 1.44MB versions successfully and with excellent long-term data integrity with my Atari equipment. Nevertheless, there are so many "bad" 1.44 drives out there, if you can find a good 720K drive, you likely will be better off. And of course, use the correct 720K media.

 

CSS may still have 3-1/2" kits for sale, and the Hyper XF is a less-expensive option. The Bob1200XL conversion is also available, although is slightly slower than the PUFF and Hyper conversions. I have had/used all these conversions.

 

Good luck with whatever you decide.

 

-Larry

 

5.25" single sided floppys will alwayse be "the standard"..

 

"The convention" these days is to emulate floppies using SIO2xxx devices instead.

 

In the late 80s, you couldn't GIVE AWAY all the 5.25" PC drive mechs that were floating around.. in fact right up until the late 90s, people were just throwing them away because they werent worth the space it took to store them. Millions of them were being jerked out of PCs and legacy equipment, and replaced with 3.5" drives (or even more modern removable storage types).

 

The reason XF551 3.5" floppy upgrades made sense in the late 80s & early 90s was that hardisk setups (or any mass storage type setup) for an Atari 8-bit still costed an "arm and a leg" so to speak. a 3.5" floppy drive mech was significantly cheaper, and 720k holds ALOT of stuff on an 8-bit machine, relatively speaking.

 

What you really should know is this: 1.44meg HD 3.5" media is crap.. 1.44meg HD drives, operating as 720k drives are less than preferable (they write tracks too narrow, and are thus less reliable and more allignment-critical, especially when exchanging floppies between drives)..

 

If you're gonna do a 3.5" upgrade on an XF551, you really need to find a REAL 720K (3.5" DSDD, NOT HD) drive mech. These things are priced INSANELY HIGH nowadayze..

 

So basically, you should leave your XF551 5.25" the way it is... If you want a decent upgrade, get someone to burn you a "HyperXF A" EPROM to replace it's firmware (fix all the bugs and add true ultraspeed).

[MEtalGuy66]

YEah I forgot abotu the track width stuff.. You are right..

 

Anywayze, its also important to note that the MEDIA has gotten progressively shittier over time where 3.5" disks are concerned.. The 1.44meg HD floppy disks sold after about 1996-1998 are not the same as the ones sold prior to that time period. They are very unreliable.. And its not the drives.. I did quite a bit of testing a few years back, involving about 30 different models of 1.44meg floppy drive on PCs at work, that ranged from late 80s to brand new units.. I did not find any difference in the performance/reliability where the era of the drives were concerned.. Some BRANDS were definitely cheaper made than others, but for instance, a brand new SONY drive which cost about $9.00 from tiger direct at the time, seemed to be every bit as good as a SONY, TEAC, or MITSUMI drive from the early-mid 90s. Some of the really crappy off-brand drives had major problems at relatively low "useage-hours".. SO yeah, over the years, alot of cheap junk has been introduced into the market.. But, I wouldnt say that repuatable manufacturers have "cheaped out" on the quality of the drives.

 

But if you take apart a HD 3.5" floppy disk from 1989-1992 era, and compare it with a brand new 3.5" HD disk, you'll notice an immediate difference in how cheaply the newer ones are made. And they are good for about one write cycle, and after that, they really arent worth the risk.

[JohnBuell]

Thanks everyone for your input. I was thinking about doing it just for the novelty (I don't even HAVE an XF551, yet...) But you've pretty much talked me out of modding it when I get one...

[spookt]

Thanks everyone for your input. I was thinking about doing it just for the novelty (I don't even HAVE an XF551, yet...) But you've pretty much talked me out of modding it when I get one...

 

If you only have 1 and it is working then seriously keep it stock. I have 2 one of which was given to me and looked like it had been "loft dropped" when I got it. The mech was trashed so I slapped a spare ST floppy drive in it and a HyperXF rom so now I have 1 stock and 1 3.5 XF.

[Chilly Willy]

The Percom drives could control two floppies, so I took a 3.5" drive in a 5.25" adapter and connected it as the second drive in my Percom. That made it easier for transferring files to the PC.

[+Larry]

That reminds me -- the ability to add a 2nd drive was a nice feature of one of the CSS XF upgrade kits. The second drive automatically took the next drive number above whatever the main drive was. I always used mine as D2: (XF 5-1/4") and (D3: 3-1/2") and the MIO as D1:. Nice setup. CSS did warn that you needed to have a low-power 2nd drive to do this, but the Sony drive that I used never caused any issues. And although I prefer images now, I still have 5-1/4" and 3-1/2" on my computer desk at all times in case I need to go to original disks for something.

 

http://www.nleaudio.com/css/products.htm

 

-Larry

 

The Percom drives could control two floppies, so I took a 3.5" drive in a 5.25" adapter and connected it as the second drive in my Percom. That made it easier for transferring files to the PC.

[Mathy]

Hello guys

 

Yes, the drives electronics (XF Dual Drive Upgrade by CSS) got hot after a while. This resulted in sectors being dropped a fixed amount of tracks more to the center of the disk than they should have been dropped on the primary drive. Using a PC power supply just for the second mech fixed that problem.

 

Sincerely

 

Mathy