Debugging IIe Modem Setup

[apache@iemend.ih.att.com (55665-Phelps)]

Need help with debugging my Dad's first attempt at getting a modem
working on his IIe. He's in Phoenix and I'm in Chicago and I entered
the Mac market in 1995 so I'm not much help for him other than collecting
the specs on his system. This is what his has:

Computer: Apple IIe Enhanced
          80 column card in auxillary slot
          Imagewriter II printer
          Dual Disk Drive
OS:       Unknown
Boards:   Apple Super Serial Board connector #1 for printer
          Apple Super Serial Board connector #2 for modem
Modem:    Apple Personal Modem, 1200 bps, no switches
Cable:    Intrec Male DB25 to DIN8 male
          Non-Intrec Male DB25 to DIN8 male
Software: Proterm v3.1
Settings: With Intrec cable, serial board set to SW1-1 off, SW2-7 off
          With non-Intrec cable, board set to SW1-1 off, SW2-2/5/7 off
Configuration Attempts:
          Tried 2 different modems, same model
          Tried the Intrec cable and non-Intrec cable
          Tried switching serial boards between modem and printer

Symptoms: 1. Modem beeps when first powered on.
          2. System boots OK with system parms showing correct data.
          3. Activate dial in Proterm, shows dialing for 45 seconds.
          4. Message "Proterm unable to connect with remote system".

Assuming he is dialing the correct number, what do you think? Does he
have the serial board set to match is modem correctly? Does that cable(s)
sound correct?

Any help would be appreciated, he's in his 70's and really wants to
get on-line to his kids.

Ron Phelps
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