On 09/29/2017 03:01 PM, Al Kossow via cctalk wrote: > > > On 9/29/17 11:35 AM, Chuck Guzis via cctalk wrote: > >> Does the little Kennedy drive have a vacuum takeup reel? > > No, they are tension arm, very similar design to the 7970 > > I wanted to compare the mechanical design of the 9000 to the 7970 > but don't know if I have the time/interest any more.
No, that's not what I meant. Some drives put a slight vacuum on the takeup reel hub, so that the tape "sticks" to the hub--no finger hole needed. I've got all the programming done for the drive, including auto retries if there's a parity error. Reading is pretty good for 50+ year old tapes (the ones I'm reading appear to be from the 1976 Viking missions). They look like session transcripts--you can see the command and the response. Still a few too many read errors for my taste, so this weekend is going to be a session with a 'scope and alignment tape. I think I've got a way to adjust skew--just hook a logic analyzer probe to each channel and set the LA to trigger on state changes. The HP box I'm using is good to about 25 nsec. --Chuck
