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can you connect to laptops using the null modem RJ 11 cable?I have a compaq armada 500 laptop with no usb or ethernet? Answered



8 years ago

It might be possible... if you have some sort of PBX software and can push out a dialtone to the other. Assuming you really do mean connecting two machines via the modem jacks, not the serial ports. I can't imagine it would be easy nor terribly fast.

If they have serial ports, use them. It should have a parallel port, so you could use laplink cables to connect the two.

But what are you trying to do? Are you trying to get data from an old laptop to a newer one? If the newer one does have USB, then you can get a 2.5" IDE external enclosure for $10 or so. Pop the drive out of the old machine, put it in the enclosure, hook it up to the new machine and transfer your files. Much easier and faster than any serial/parallel transfer.

If you're trying to network the two for live file sharing and such, it's probably worth investing in a PCMCIA network card.

If both laptops have a serial connection, then yes. You'd have to run an appropriate serial communications application on each end, of course.

If one of the laptops doesn't have a serial port (some recent laptops don't), you could get a USB-attached serial port.

If the Compaq has a CD burner, "sneakernet" (moving physical media between the machines) may be a better answer to copying files around.

.  I've never used direct modem-to-modem communication, so I'm not going to swear that it is even possible or not.
.  I have used the serial ports and a null modem cable to "network" two computers. But that was many, many years ago ... in a land far, far away ...  Try searching for "null modem +serial" (w/o quotes)

oh!  Duh!  I was thinking null modem with a rs232 db9 serial cable...whoops...

.  heehee  I did too ... until I remembered that RJ connectors are telephone/Ethernet/&c connectors. A quick Google and, yep, RJ-11 is two-line (four "pin") telephone.

Little known fact - you can run VERY short runs of cat3 rj11 ethernet at 10/100 with varying reliability...if you're totally out of cat5+

You can...it's been a LONG time since null modem was really used for anything much.  any chance for a pcmcia slot?

How old is this laptop?!  might be easier to pull the drive to get data off.

There should be two PCMCIA slots on the machine. As I recall, the baseline Armada E500 package came with Win 98 SE installed. For a little more, you could get the hot new Win 2K OS instead. That's how old it is.

I bet a usb pcmcia (even usb1) could be had on ebay for a dollar...