1050 passed Tests, Can't Format

[Tonyscouter]

I ran the 1050 diagnostic disk and passed all the tests but still can't format a floppy disk.  Is there something wrong with the drive or is it because it is a 30 year old floppy disk?  Can floppies lose their ability to be written to?  The drive can read disks fine.  I just don't know what to try next.

[+bf2k+]

Is it a DSDD or SSDD disk?  And not a Hi density disk.  A stock 1050 won't format a HD disk.

[Nezgar]

What program are you using to measure RPM? I know there is one as part of SpartaDOS, as well as the Atari 1050 diagnostic utility... (though that program shows the timing in ms per revolution versus revolutions per minute)

 

These disks can absolutely lose their ability to be read or written over time... It's good to test disks you plan to regularly use with an occasional full re-format. A known good working 1050 is also useful if you have one. Also make sure the read/write head is clean - dirt on it can reduce the ability for successful data read/write, as well as cause physical abrasion and scratch the disk further degrading your disks...

 

Also inspect the drive belt beneath the mechanism - these are also often worn out, loose, or falling apart and can also lead to erratic RPM if it is slipping or the disk itself is too hard to turn within a disk sleeve with too much friction...

[ndary]

Simple solution: you have dust in the Write protect sensor… just clean it with alcohol and a qtip 

 

Ndary

[TGB1718]

I have a few different types of floppy disk, although all "new" i.e. never used, some will format, some won't

there doesn't seem any reason why the one that fail actually won't format.

 

as @bf2k+ says, if they are HD disks, they will never format

[+kheller2]

15 hours ago, Tonyscouter said:

I ran the 1050 diagnostic disk and passed all the tests but still can't format a floppy disk.  Is there something wrong with the drive or is it because it is a 30 year old floppy disk?  Can floppies lose their ability to be written to?  The drive can read disks fine.  I just don't know what to try next.

 

You have not provided enough information for us to help you out enough.  I'm assuming since you ran the 1050 test and they all passed that RPM speeds is correct.  Assuming you have a DOS 2.x disk you can use, can you create new files, and delete them?  Just copy a file on the disk and give it a new name. If that works, and you can read it back and then delete it, the problem might be with the format circuity, specifically the required voltages to format.  There are few threads here on how to fix that.

 

But first .. please validate that you can write to a working disk and modify its contents.

 

[macsonny]

So did it pass ALL the 1050 drive diagnostics including read/write, speed and track 0?

[Tonyscouter]

On 10/23/2022 at 10:27 PM, bf2k+ said:

Is it a DSDD or SSDD disk?  And not a Hi density disk.  A stock 1050 won't format a HD disk.

Thanks for the info, I put aside all the HD disks I had mixed in.

[Tonyscouter]

On 10/24/2022 at 12:41 PM, kheller2 said:

 

You have not provided enough information for us to help you out enough.  I'm assuming since you ran the 1050 test and they all passed that RPM speeds is correct.  Assuming you have a DOS 2.x disk you can use, can you create new files, and delete them?  Just copy a file on the disk and give it a new name. If that works, and you can read it back and then delete it, the problem might be with the format circuity, specifically the required voltages to format.  There are few threads here on how to fix that.

 

But first .. please validate that you can write to a working disk and modify its contents.

 

I did verify that I can write a file to a working disk.  I'll try cleaning the write protect sensor.

[+kheller2]

The problem isn’t the write protect sensor if you can write to the disk.  
See if this thread helps: 

 

 

[_The Doctor__]

look at your other thread about the same thing, you may need to clean the head again as well. then pick up where the check list is, you'll prolly end up at the 3086