Double sided floppy???

[ahelg]

I heard from someone that WHSmith in the UK has branded and is selling double sided floppy disks. Basicly you put it in, transfer data. Take it out, turn it upside down and put it back in again, thus giving you two floppys in one. Is this for real?

[Kemp]

AFAIK, all (current) floppies are double-sided, drives have read heads for both sides already. I think your source was either having you on or was a bit confused.

[Solar]

Or outdated. Back in the times of the 5,25" floppy (1541 anyone?), you could buy floppies single-sided or double-sided. Usually, you could format the single-sided ones on both sides - and I still have a hole-puncher to do the necessary modification to the SS floppy. The DS ones were just tested to work on both sides, but usually cost a hefty premium.

3.5" floppies, on the other hand, are always "double-sided", because (as Kemp said) 3.5" drives have two read/write heads, one for the top and one for the bottom side. (Like the 1571 floppy drive for 5,25" disks, you didn't have to turn the disks over in that drive either.)

[ahelg]

Ah well, he must have got it wrong. I seem to remember seeing the words double density on some floppy disks. I supose thats what fooled him.

[earlz]

actually you use to be able to buy single sided 3.5's that were like 720kb

[ahelg]

Ah so thats why my BIOS has an entry for 720kb floppy drives. Always wondered what they were. I guess they were from before my time .

[DynatOS]

Agreed, 3.5" disks were always double-sided. However, the double-density 3.5" disks were 720KB ones. The high-density (most common) disks are the 1.44MB ones.

Think of it as the difference between CD and DVD formats on standard 120mm discs... and speaking of LD is like talking about the 8" FD

[df]

well disks used to be;

single sided, single density (eg: 180kb 5.25)
single sided, double density (eg: 360kb 5.25, 720kb)

double sided, double density (eg: 1.44mb)

(what they classed 2.88s as I dont know)...

[Candy]

(what they classed 2.88s as I dont know)...

I know the short names, SD, DD, HD and ED, but I think it's just "extra density" or such.

[blip]

About 720KB floppies, I heard they were pretty much the same as 1.44MB ones except for a hole (or lack of?) in the disk and they were sold for less. I read of a modification to drives that you can perform to make it use 720KB floppies as 1.44MB ones, but of course it's irrelevant nowadays and I have no idea where the doc is located.

According to http://www.nondot.org/sabre/os/files/Di ... diaIDs.txt 720KB floppies are double-sided but have half the sectors per track than the 1.44MB variety.

Now I have a friend who has an 8" disk from his dad. I think there is terminal software stored on it but I do wonder how readable it is by now.

[DynatOS]

blip is correct. The 720KB 3.5" floppy was DS-DD. The 1.44MB 3.5" floppy was DS-HD.

[Pype.Clicker]

floppy (1541 anyone?)

formatting

crrrouch krr Krrr kRRrRr KrrrRrr
tttrrrkTrrrktrrRrrkttRrk
crrrrrrrrouchhh krr krnnch krkrrr krnnnch krNnch
crrrouch
crrrrrrrrrrrrrrrrrrrrrrrouuuuuch
tttrrrkTrrrktrrRrrkttRrk tttrrrkTrrrktrrRrrkttRrk
...

for about 15mins/floppy ...

[Xardfir]

Hiya, I remember using a little board cut out with my 3.5" 720k disks. It had a little hole and all you had to do was use a handy drill. Still got a ton of "converted" disks around.
2.88MB was sold here as (QD) Quad density. Only a few IBM systems sold with the actual drive.

If you want to go a bit further, there were some 10MB disks around in the late 1980's that used optical tracking on both sides (kind of like a magnetic / optical hybrid). Innovative but desperate.
CD's kicked them off the market.

[Neo]

Yeah CD's have pretty much obsoleted floppies now.
A friend who was getting a new system the other day was laughed at when he asked for a floppy drive. ;D
Not sure how long CD's will last now with DVD's and blue ray discs on the scene.

[df]

I remember using a stanly knife (boxcutter) to notch my c64 disks that I would buy in packs of like 50 then I bought this little jigger that did it for you...

I wouldnt say cd's replaced floppies, usbkeys replaced floppies.