SAC.DYESGPF@E.ISI.EDU (07/11/88)
Pertaining to the following from KOZIARZW@RADC-LONEX.ARPA > Curiosity finally got the better of me, I decided to check out the affect > of mixing 360K and 1.2M 5.25 disks in each others' drive. Guess what -- > THEY SURVIVE WRITE OPERATIONS UNHARMED!!!! Each will return a 'SEEK ERROR' > but data will not be destroyed. Note that I did not perform an exhaustive > test; but my preliminary finding should put Gern a little more at ease. You can even format a DSDD diskette at high density, with many bad sectors and rapid deterioration of recorded data. Quad Density (720K) diskettes may do better but there is no significant price difference between the 1meg rated and 2meg rated 5.25 diskettes at this location so I "go for the gold". > I do agree with Gern that media of different storage capacity should be of > different physical size. But, 1.2M 5.25 drives can be found at attractive > prices, we know they work, and I have posted the pinouts for the adaptor > cable as well as the strapping/jumper settings for the Mitsubishi HD floppy > drive. Until the 3.5 drive mysteries are resolved and the price falls, I > will continue with 5.25 HD. The June 1988 _COMPUTER SHOPPER_ has several 3.5" drives available in the range of 119 to 149 dollars (mostly Mitsubishi's - Gern, you should like that) One of our doctors here had a 3.5" 720k drive installed in his Z157 as his drive B. Because his original cable was a bit short of reaching the connector on the back of the drive the local service center tried to put a Z248 cable on the drive but found that it needed an XT style of cable. Sounds like the connection for the 720k is the same as 360k 5.25, now I wonder . . . do you suppose the 1.44meg might use the same connection. Of course the 1.44meg may have the same pinout as the 1.2meg 5.25". I plan to know in the near futur. > NOTE: BE SURE OF WHICH DISK YOU ARE FORMATTING, IF USING MIXED 5.25 DRIVES!! > FORMATTING CAN AND WILL DESTROY DATA; IF 'DIR' RETURNS A 'SEEK ERROR' > DO NOT ASSUME THE DISK IS UNFORMATTED; IT MAY BE THE OTHER CAPACITY!!! The easiest way to determine if you have a high density disk or double density is to look in the read/write window - the HDs are the ones you can use as a mirror; DDs look like 000 sand paper by comparison. That is another reason not to use the DD disks in a high density drive, I suspect that the r/w heads are smaller and more prone to wear. Al Holecek | ...probability factor of one to one...we have nor- <SAC.DYESGPF@E.ISI.EDU> | mality, I repeat we have normality. Anything you ----------------------- | still can't cope with is therefore your own problem.