Date: Thu, 22 Nov 2007 07:58:17 -0500 From: "Richard A. Cini" <rcini at optonline.net> Subject: Re: FD400 drive troubleshooting >The way that the service manual tells you to check the speed is the pulse >width on a specific test point on the PCB. I was just going to use a laser >tach on the spindle...but I have to get a tach first :-) ----- Strobe disk?