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Direct Modem-Modem connection

I know it's possible to connect 2 modems directly (like a null modem) and to initiate a communication between them with some AT commands. Is there someone how can give me precise steps?
I read that I must do ATA on Modem1 end some commands like force "GO Online" on Modem2. But I never succeed!

Thanks for any help.
Bye bye

David

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rayt333

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rid

For connecting two modems, I have had the following recommendation from a purportedly tech-savvy person:

If your modems are not explicitly said to support leased line or private line communication, you will have to fool them into believing they are on an ordinary phone line. The prerequisite is a "line voltage", which ordinary modems uses to understand that they are on-line. This line voltage can be simulated by connecting a 9-25 V voltage source (battery) in series with the modem - line - modem setup.

Next step will be to force handshake start - issuing the ATD command (Dial!) on one end. The other end MAY need the ATA command (Answer!), unless it can be set to answer automatically on handshake tries. All such technical things should be in the modem manual.

I strongly suggest you go into this using proper hardware modems and a good portion of patience.

The battery mentioned should be inserted between one strand of the phone line (which is two-strand) and its modem terminal. Easiest way to connect is probably to snip off one strand in the cable and connect the battery into the "gap" thus produced.

Regards
/RID

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RDavid

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