[comp.dcom.modems] Need Info on modem

sean@engr.uky.edu (Sean Casey) (07/21/87)

Hello.
   I recently became the proud(?) owner of a DATAPHONE 212A from Bell.
It is a direct-connect 300/1200 auto-answer modem and there is where
my knowledge ends.  Somehow, it is hooked up to the phone lines but
the exact nature of the connection escapes me.  What I am really interested 
in finding out is what all this thing does.  It has 5 buttons
across the front marked AL, ST, RDL, DL and HS.  The only one I know
what to do with is the HS (High Speed?) which alternates between 300/1200. 

There are also lighted indicators TR, MR, HS, RD and others (not listed
in order because I can't see the ones that never light up).
Obviously, I need a *lot* of information so any is greatly appreciated.
 
Does this thing have a command set to dial? To autoanswer on the second
or third rings? Any dialing memory? etc etc etc
 
              Any info, please send it to me at any of the below.
 
                             Thanks in advance,
                                        DC
-- 
Dan Chaney via Sean's account   DOMAIN: sean@engr.uky.edu
                                  UUCP: cbosgd!ukma!ukecc!sean
                                BITNET: EXT698@UKCC 
"Write if you hang by your thumbs"    DISCLAIMER : Mine!!  All mine!!

jbh@mibte.UUCP (James Harvey) (08/12/87)

In article <1453@ukecc.engr.uky.edu>, sean@ukecc.UUCP writes:
> 
> 
> Hello.
>    I recently became the proud(?) owner of a DATAPHONE 212A from Bell.
> It is a direct-connect 300/1200 auto-answer modem and there is where
> my knowledge ends.  Somehow, it is hooked up to the phone lines but

Here  is how to hook up the 212 modem.

Viewed from the rear, the right hand connector (MALE) is the telephone
line interface, the left (FEMALE) is the RS232 connector.

You will have to make a cable to connect the telephone leads.  Get
a regular telephone, the 212 will not dial for you.

Connect the telephone to pins 21 and 22

Connect the telephone line to pins 7 and 8

Connect a single pole single throw switch to pins 5 and 25

Now when the switch is closed, the modem should cut the line through
to the phone and you can dial normally.  When you hear the far end's
answer tone, throw the switch to open, this will signal the 212 to 
pick up the call (Terminal Ready must be high).

You may find the levels are set too high if you live close to the central
office.  
A normal 212AR modem transmits  at -4 dbm and requires an external pad 
to make a central  office level of -12 dbm.  Leave all the buttons out
for 300 baud, push hs in for 1200 baud.


Hope that helps

Jim Harvey
Michigan Bell
29777 Telegraph
Southfield, Mich.  48034

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