HP82161 tape splicer?? - test-drb@ccmp.vtda.org

31 Jul 2000

...
  > > Has anyone ever seen a splicing jig and tape
(or any other form of repair
...
  > > kit) for the tape cassettes (HP82176??) used
in the HP82161 tape drive.
...
  > > I'm trying to read some old tapes and
the magnetic tape on one of them
 > > has come unstuck from the leader. I think it would be possible to stick
...
    them together again.  
 How wide is the tape?  If it's not too narrow, you could try 1/2" audio  
 I think I've been lucky for once. I cracked open the cassette and extracted 
...
  the ends of the tape. I held them against the tape in
a random 
 compact cassette [1] and they seem to be the same width. Which means I 
 can use a cassette tape splicing block and tape. I know I have one of 
 those _somewhere_, but even if I can't find it, I don't think they're 
 particularly hard to get... I've not tried it yet, but it's 
 well worth a try. 
I'm a little surprised that some digital casettes were manufactured
using the sonic-welding technique, instead of using screws to hold
together the shell halves. FWIW, they do make digital cassette with 
screw assemblies.

And yes, as you've discovered, digital cassette tape is the same width
as audio casette tape. The differences are in the oxide formulation.
Digital casette tape needs little in the way of frequency response,
and the response curve should be as flat as possible, whereas (IIRC)
audio casette tape tends to bump up the low and high ends.

Also, digital tape needs a very low dropout rate, so they end up
with a more uniform oxide coating. And, I've never seen them use 
metal or chromium dioxide for digital cassettes. Lastly, the
substrate needs not to stretch, so long tape lengths are out.

regards,
-dq