Giving up: 9 sectors missing

[burenkov]

The problem:
Failing to create images of old Atari ST disks that I know work.

The setup is :
.\gw.exe info
Host Tools: 1.16.2
Device:
Port: COM7
Model: Greaseweazle V4.1
MCU: AT32F403A, 216MHz, 96kB SRAM
Firmware: 1.4
Serial: GWB0B57DE85976C01007B41705
USB: Full Speed (12 Mbit/s)

• internal 3.5" floppy Citizen Z1D / Z1DE-68B 072432 A-69.

Command:
.\gw.exe read --format atarist.360 images\atari_basic.img

Output:
Reading c=0-79:h=0 revs=2
Format atarist.360
T0.0: IBM MFM (0/9 sectors) from Raw Flux (9123 flux in 401.16ms)
T0.0: IBM MFM (0/9 sectors) from Raw Flux (23103 flux in 1002.60ms) (Retry #1.1)
T0.0: IBM MFM (0/9 sectors) from Raw Flux (37175 flux in 1603.96ms) (Retry #1.2)
T0.0: IBM MFM (0/9 sectors) from Raw Flux (50859 flux in 2205.33ms) (Retry #1.3)
T0.0: Giving up: 9 sectors missing
T1.0: IBM MFM (0/9 sectors) from Raw Flux (9136 flux in 401.08ms)
T1.0: IBM MFM (0/9 sectors) from Raw Flux (23164 flux in 1002.50ms) (Retry #1.1)
T1.0: IBM MFM (0/9 sectors) from Raw Flux (36851 flux in 1603.81ms) (Retry #1.2)
T1.0: IBM MFM (0/9 sectors) from Raw Flux (50654 flux in 2205.23ms) (Retry #1.3)
T1.0: Giving up: 9 sectors missing
... and so on, reading 0% data.

Solution:
Ensure that the floppy drive is level. In the failed attempts, the front of the drive was lower than the top at an incline of <10 degrees.

New output:
Reading c=0-79:h=0 revs=2
Format atarist.360
T0.0: IBM MFM (9/9 sectors) from Raw Flux (91256 flux in 401.22ms)
T1.0: IBM MFM (9/9 sectors) from Raw Flux (93997 flux in 401.14ms)
T2.0: IBM MFM (9/9 sectors) from Raw Flux (81634 flux in 401.16ms)
T3.0: IBM MFM (9/9 sectors) from Raw Flux (82322 flux in 401.14ms)
T4.0: IBM MFM (9/9 sectors) from Raw Flux (82090 flux in 401.14ms)
...
Found 720 sectors of 720 (100%)

[burenkov]

This is just to say that these old drives may behave erratically. I suspect that there may be some spring in the drive that is no longer fixing the disk properly if the drive is not level.