5.25" drive jumper settings

[clh333]

It could be that the drive electronics have a problem.

I found another variable: drive jumpering.  A little background:  Recently I had been testing some 5.25 inch Kaypro drives, from Epson and Toshiba, using the SCP as a drive-exerciser and measuring max track and drive speed.  I was puzzled by the fact that the drives would respond to the track test but not the speed test.  What would happen is that after starting the speed test the blue light on the SCP board would flash for a fraction of a second and go out.  The drive motor would not start and the test would not display any speed data.

I tried the same tests with a 3.5-inch Samsung drive attached to the SCP and it completed both successfully, so I eliminated the SCP as the source of the problem.  I looked at the 5.25" jumper settings here and selected the Toshiba, using D2, HM, LD and TM.  The drives had come jumpered to use HD instead of HM; when I made the change the drives responded to the speed test.

From this I concluded that the SCP must be monitoring the motor start signal in order to perform the speed test.  Can you confirm this?

Thanks,

-CH-