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Value of 720kb Floppies

Depends on the buyer's need. I have a nearby thrift store that often gets in 3.5" floppies, both DD and HD, selling 50-packs for US$3 when they're in, or 10 disk boxes for US$1.50. If they weren't around, I'd be reusing my other disks more frequently, or paying more if they turned up elsewhere.

One other place nearby decided floppies are a displayable "antique", asking $10 for a single 3.5", $25 for a 5.25" and $150 each for some 8" disks. They never sold any so far as I could tell, and shut down after about 6 months since this was pretty common pricing practice on other items.
 
...and I imagine that there's still plenty of surplus from the duplicator market if you know where to look. But you have to buy your floppies by the 500 or 1000 bulk box. I think I've still got a bulk box of new Sony DS2Ds somewhere. Maybe I'll wait a few years and dribble them out on eBay for $2 each... :)

I still have big piles of mailers as well.
 
I am sure you can still find them in bulk cheap somewhere, but most have been liquidated by now from the duplicator market. I wish I had purchased more from www.meriteline.com when they were dumping them for 500 @ $20 bulk. I have stock of everything except 1.2MB 5.25 which are not realy needed much these days.
 
If anyone wants them as a collector's item, I have about 16 or 17 single sided, double density 3.5" diskettes laying around.
 
What I'd really like is a source of genuine 720KB drives. I need a few. (Except for a few older drives, most 1.44MB drives can not be strapped/jumpered to do only 720KB. They rely the sensor to figure out what data rate to use.)
 
mbbrutman said:
What I'd really like is a source of genuine 720KB drives. I need a few. (Except for a few older drives, most 1.44MB drives can not be strapped/jumpered to do only 720KB. They rely the sensor to figure out what data rate to use.)
Click to expand...

I seem to remeber that Teac FD235HFs can be "hard jumpered" (there are pads on the PCB that must be soldered). The problem is that not all have the capability to provide a "Drive ready" signal on pin 34. Similarly, most HFs can be hard jumpered for 1.23MB operation.
 
I'll look around - it's another project on a very long list.

While 1.44MB drives can operate on 720KB media and use the double density data rates, I'm finding that my PCjr and other machines with older BIOSes and double density controllers can't boot from a 720KB double density diskette in a 1.44MB drive. I'm not sure what causes it, but on the one genuine 720KB drive that I have stashed somewhere it works.

(Imagine removing the existing 5.25" double density floppy drive and putting a 3.5" drive in it's place. A 720KB drive looks electrically like a 5.25" drive, and uses the same data rate. Those work *exactly*, and the BIOS doesn't know or care about the extra tracks. But 1.44MB drives don't seem to work to boot the machine, even if the correct media is used. It's like something is confused/wrong.)

I've not put a lot of work into it so don't go bananas - we can start another thread if it gets serious. :)
 
Mike, try isolating pin 34 on a 3.5" HD drive and see if that makes a difference on your Peanut. In theory, but for pin 34, there should be no discernible difference between a 720K drive and a 1.44M drive operating in 720K mode.
 
Hi
An optional circuit to make a drive ready signal is
to use a retriggerable one shot. Have it time for
just over one revolution. Trigger it with the index signal.
On drives that don't have a drive ready signal,
both the read data and the index are blocked until
the drive is ready. Either can be used to recreate
the "drive ready" signal.
Dwight
 
I have 15 of the first one, and only 1 of the second one, which i know is the oldest 3.5 in my collection, note the difference in shape of the shutter. You have to manually open the shutter on the disk.
 

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Here's my collection.

s6orhk.jpg


Two variations from 3M:

6z4s2f.jpg


2ywv4m1.jpg


A rather grimey TDK:

25rgp5v.jpg


HP diskettes which could work with either early manual shutter drives or later auto shutter drives: if you slide the shutter all the way open (past the amount which a normal drive opens it), the shutter locks, and then you pinch the edge of the disk to release it. Otherwise the shutter opens and closes under spring tension, as normal.

2ymatlz.jpg


And finally a double-sided Sony disk, still in the original shrinkwrap and plastic jewel case(!):

fvzf2t.jpg
 
Dwight Elvey said:
Hi
An optional circuit to make a drive ready signal is
to use a retriggerable one shot. Have it time for
just over one revolution. Trigger it with the index signal.
On drives that don't have a drive ready signal,
both the read data and the index are blocked until
the drive is ready. Either can be used to recreate
the "drive ready" signal.
Dwight
Click to expand...

i've got a little program for an 8-pin PIC. No timing components at all, just the bare IC and 5 volts. Anyone can drop me a line if they're interested in the code. At about $0.79, it's probably cheaper than a one-shot--and it wats for a programmed number of revolutions before it asserts READY/. Lots of functionality left over, so it could handle more than one drive or even maintain a permanent log of drive speed in the EEPROM memory.
 
Now that my thread has been throughly hijacked :p I'd like to go back to my origional question. The current value of say a 10pc parcel of 720kb disks. Addendum question. Would anyone here be interested in buying some them?
 
On the high end they seem to be in the $9 - $10 range on eBay.

On the low end I've been selling them for $2.50.

The prices above are for new, sealed boxes of ten.
 
Stone said:
On the high end they seem to be in the $9 - $10 range on eBay.

On the low end I've been selling them for $2.50.
Click to expand...

I guess 10 bucks might seem OK to someone who doesn't have an internet connection with Google on it. lol The rest of us would probably just get them for the regular price of $1 each from suppliers like the ones that Agent Orange mentioned.
 
Ole Juul said:
I guess 10 bucks might seem OK to someone who doesn't have an internet connection with Google on it. lol The rest of us would probably just get them for the regular price of $1 each from suppliers like the ones that Agent Orange mentioned.
Click to expand...
You should read the *entire* post before commenting.

$1 each = $10/box of TEN which is clearly what the post you truncated and the previous post by k2x4b524[ mentioned. Jeez Juul!
@ $10/box of ten the individual price = $1.
@ $2.50/box of ten the individual price = $.25

BTW, how does 'someone who doesn't have an internet connection with Google on it' get to eBay to even know this???

Math & reading lesson over. :)
 
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