T A R Advice?

[JBROOKSHIRE at USC-ECLB.ARPA]

Under System_3, we are trying to use TAR to move files from system floppy to
hard disk, and continue to get "DIRECTORY CHECK SUM  ERROR"s, and have tried
every variety of directive we can think of, as variations on:

     DD if=/dev/rfdsssd | tar xvf -

etc, etc, etc....
Can anyone help?
Under what conditions do directory check sum errors usually occur, etc?
Any help greatly appreciated.
Jerry Brookshire
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