Replace roller rubber on HP 9825 tape drive

[Tony Duell]

> 
> Well, I finally got around to attempting to re-spool this stupidly
> designed tape.

It's actually avery ingenious design (it's the same design, basically, as 
QIC tape cartridges). Remember you want a constant tape speed past the 
head. By driving the outside of the tape spools at a constant speed 
(that's what the belt and drive puck do), rather than turning the spools 
themselves by their axles, that's exactly what you get. It avoids the 
capstan, pinch roller, slipping clutches, etc, used in audio tape and 
cassette recorders.

> 
> Your description sounds like a different tape than what I was dealing
> with.  The tape did not come off of either spool but was instead attached
> onto both spools.

THere were several designs, sure...

> 
> At any rate, the stupid tensioning belt (whatever its called) broke on me.
> Oh well, fuck that tape.  I'll try to read it anyway (is the tensioning
> belt necessary?)  I also noticed numerous spots on the the tape where the

Of course the belt is necessary. It's how the tape is driven. You can 
borrow one from another tape cartridge.

> oxide had flaked off, so any re-attempt may well be futile.  Whoever

Obviously you've lost data where that oxide is missing. You'll also have 
problems becuase these drives use optincal BOT/EOT detection (there's a 
small hole in the tape, a mirror as part of the cartridge housing, and a 
bulb/photodetector in the drive). The system will think it's got to the 
end of the tape if it finds a clear spot.

> designed these tapes is a moron.  I can't imagine how impossibly expensive
> it must've been to manufacture them.

See above. Tell you what, you see if you can come up with a better design.

> 
> I hate computers.

Feel free to send me all your collection.

-tony