Re: [NTLK] Modem to Modem connection method

On Mar 30, 2006, at 12:37 AM, matt wrote:
>
> Jon Glass wrote:
>
>> On 3/29/06, June Tate <june@theonelab.com> wrote:
>>> Since my modems don't support dry wires, I'm just going to build a
>>> serial cable and stop mucking around with modems. =op
>>
>> June-
>>
>> would it work to plug a y-jack into one of them (RJ11) and plug the
>> empty plug of the Y-jack into a live phone line? Would that be
>
> I got around that problem by telling them newton to ignore dial
> tone, and on
> the pc side turned off all data correction, and ignore dial tone.
> then when
> you tell the newton to dial it just dials as of there isnt even any
> line
> connected, now right as it stops dialing its sending a signal . the
> line now
> has a feed, manually answer from the pc side. the pc will see a
> signal . I
> know its a bit unorthadox but it works. I have hooked up to macs
> this way.
> nelson
Heh, well that's what all those AT commands do that I posted about
earlier. The problem is, not all modems will work on a straight patch
cord, since most of them expect to see at least a 20mA current on the
line. Phones and modems generally manipulate that current to produce
the sounds on the line instead of producing the current on their own.
In fact, that's why you can take an old-style rotary phone and attach
it to the phone outlet only (without a power supply) and still use
it. The phones feed off of that 20mA current on the wall jack to
power themselves and send the signals -- no current means no signal.

Problem is, when there's no 20mA current on the wire (like in the
single patch cord going between two modems) there's nothing for the
modems to modulate, thus preventing communication between them.

--
June Tate
june@theonelab.com
http://www.theonelab.com
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