John and Frank,
Thanks for the replies.

If I can verify that the "letter" suffix is a change that does not
affect the operating parameters, then I'm good to go. I only want to
know because I am trying to determine if all suffix numbers all inter-
changeable. In other words, can a DT-1704C be used in place of a
DT-1704B and visa-versa.

Thanks again,
Kevin.