On 10/4/20 8:12 PM, jim stephens via cctalk wrote: > > > On 10/4/2020 4:00 PM, Chuck Guzis via cctalk wrote: >> On 10/4/20 1:50 PM, J. David Bryan via cctalk wrote: >>> <snip> >> I don't believe that you're missing anything. When I process these >> files, I mask off the lower 24 bits as the block length. A 16MB tape >> block is impossibly large in any case. >> >> --Chuck > Oil logging tapes write 9 tracks with no inter record gaps or file marks > till EOT. I'm guessing you've not digitized any of those?
A couple of years ago, one of the NASA logging units turned up for not much money. Big flight case. Basically consisted of a Kennedy incremental drive (i.e. stepper) brought out to several BNC connectors. My recollection is that the Kennedy 9000-series unit was NRZI and likely 800 bpi. Unlikely that you could get 16MB on a 10.5" reel with that. Probably unreadable on standard tape drives with limited formatter memory. I've also mentioned CDC 7-track "long tapes". I've certainly seen the 9-track analog telemetry tapes also, but they're a much different kettle of fish. --Chuck
