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HP Forum Archive 14

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What's so special about a low density 9114B disk?
Message #1 Posted by Mike on 23 July 2004, 12:25 a.m.

I must be missing something. What is so special about a formatted low density disc for the 9114B, that works in conjunction with an HP-41? There is one on ebay and someone bid $5 for 1 formatted low density disc.

I buy disks for about 10 cents each (low density) and they work just fine in a 9114. Is there some special problem with discs for use with the 41 or something?

I have used 10 cent low density disks with the 71 and 75 with the 9114. I don't use this drive with a 41 so I may be missing something?

Can someone shed some light on this?

      
Re: What's so special about a low density 9114B disk?
Message #2 Posted by Eric Smith on 23 July 2004, 2:16 a.m.,
in response to message #1 by Mike

The 9114 uses standard density 3.5 inch diskettes; there's nothing special about them, and it doesn't need different ones for the 41, 71, or 75.

High-density 3.5 inch diskettes technically are not suitable but may work in a pinch. The coercivity is about 660 for standard density and 720 for high density. That's a different situation from 5.25 inch diskettes, where the high density was more than twice the coercivity of the low density.

            
Re: What's so special about a low density 9114B disk?
Message #3 Posted by David Smith on 23 July 2004, 12:17 p.m.,
in response to message #2 by Eric Smith

I have used high density disks in these machines for years without any problems at all (going the other way might cause problems though). You do have to cover the density hole... the sensor that HP uses to detect a disk is mounted there.

            
That's what I thought
Message #4 Posted by Mike on 24 July 2004, 10:44 p.m.,
in response to message #2 by Eric Smith

I wonder why the seller would think he would ever get $5 for one of these discs that can be had for pennies. The reason I asked is because one of the bidders is a well known HP collector. ????

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