There are many options to connect Macintosh computers on LocalTalk to a
VAX. However, since you already own MacTerminal 3.0 and want to retain
that investment, this list narrows down a bit. One option is software from
Synergy described here:
VersaTermServer is a Macintosh CommToolBox-based application which allows
any Macintosh to act as terminal server. It supports 24 output ports, and
two different input methods. Inputs can be AppleTalk ADSP Tool over
LocalTalk, VersaTerm Telnet Tool over Ethernet, and Apple Modem Tool over
serial line. Outputs can be LAT Tool to VAX hosts, Telnet Tool to UNIX
hosts, or Modem and Serial Tools. Your Macintosh computers on LocalTalk
can use the AppleTalk ADSP Tool to the VersaTermServer, and then LAT from
the Server to the VAX. Each supports 24 output ports so you will need two
servers running.
On AppleLink, you can find contact information for the various vendors by
clicking the Library Index button to view the folder structure in the Tech
Info Library. An alphabetic listing of vendors is in the Third Party
Company Directory folder.