What is with this character set?

[J.D. Baldwin]

I use NCSA telnet 2.2 on a Zenith 248 (AT compatible).  I work on a system that
runs 4.3 BSD Unix.  Sometimes, when I accidentally list out a binary file,
I get the usual garbage characters on my screen.  Then, when I stop the
listing (either by waiting for it to end, or by hitting ^C), everything
I type (or is typed back to me) is in "garbage" characters--the character
set seems to have been mapped to the upper half of the IBM extended character
set.

Nothing I do (Alt-R for reset, clear, stty, etc.) clears this problem, 
short of logging off and logging back on.

The same thing has happened to me working at home from Procomm 2.4.2, which is
why I think that the solution lies in comp.unix instead of some group about
terminals.

Thanks in advance for any help!  If replies are by e-mail, I'll summarize.
--
>From the catapult of:               |+| "If anyone disagrees with anything I
   _, J. D. Baldwin, Comp Sci Dept  |+| say, I am quite prepared not only to
 __||____:::)=}-  U.S. Naval Academy|+| retract it, but also to deny under
 \      / baldwin at cad.usna.navy.mil |+| oath that I ever said it." --T. Lehrer
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