mlwillia@CRDEC4.APGEA.ARMY.MIL ("Michael L. Williamson") (01/04/90)
Hello Net
I am new to this interest group. I recently purchased a used and ancient
Anderson Jacobson Modem 1234A without documentation. Many of you might say
that wasn't smart, however, it was cheap and I made sure it worked with
my primary connection site ahead of time. I installed it on my Mac SE using
a cable from Black Box Co. (25 pin Male DB to 8 pin minidin). I am able to
communicate only with the mainframe at Work (I believe a UnivaC) And no other
mainframes or microcomputer bulletin boards using the same set up parameters
on Versa Term telecommunications software:
1200 Baud
no parity
1 stop bit
8 data bits
An interesting observation I made is that on dial in, our mainframe is the
only computer system that gives an audible dual tone (a lowere pitch for
about 7-8 seconds followed by a higher pitch). It is at the higher pitch
that the modem finally connects. All other systems I tried give a single
monotone throughout. Does anyone know the significance of the presence of
these two tones? I tried sending a return several times to connect but this
doesn't work either.
I have several questions:
1. Does anyone have any ideas what may be happening?
2. does anyone have or know where I may find/ obtain a copy of the
manual/ documentaion for this modem?
3. In the meantime, can anyone give me the proper "A" switch designations
ie. which switch controls synchronus/ asynchronous, which is forced
DTR. I obtained a manual for the AJ1233 from a friend here. Is the
AJ 1233 similar or analogous to the 1234A?
As you can see, I am new to telecomm. Your patience is greatly appreciated.
Thanks in advance.
Mike Williamson
Aberdeen Proving Grounds, MD
mlwillia@crdec4.apgea.army.mil