Since most modems use commands comparable to the Hayes "AT" set, I'm scratching my head on this issue I'm having. I have a USB modem 'dongle' that works on a hit-or-miss basis. It used to work flawlessly. I began noticing that many of the integrated modems in systems that I dial into have stopped connecting. Once I started audible monitoring, In noticed that the modems on the far end have started answering in fax mode (an experienced modem user can tell by the sound). I put two and two together and determined that the ones called by this dongle modem are the ones that mysteriously start answering as a fax. The only solution is to reboot the distant systems, requiring a dreaded site visit; the exact reason why we have these modems in the first place.

Another modem I use in my desktop PC has worked flawlessly for years and years. It rarely lets me down, despite the fact that it's hard to get a real phone line any more. Somehow, some way, it always manages to negotiate a connection.

So here's my question. It is obvious that this dongle modem is sending some kind of reversal command to the distant modems to make them start doing this. Again, through the process of elimination, this ONLY happens when I call an otherwise perfectly-functioning modem from the USB modem. What I need to know is what AT command can I send to this dongle modem to disable its fax capabilities and more importantly, how to stop it from sending commands out to the others. I've scoured the lists of AT commands, but the way those things are written isn't very clear to me as to which one is causing the problem. I'd love to disable the fax functionality on this thing entirely, if that's possible.

The terminal software that I am using doesn't seem to send the desired initialization string of commands that I'd like. That's OK, I don't mind just entering the ones that are important each time I use it. I just need to know which command is the culprit for turning my large systems that are hundreds of miles away into fax machines. AT&F and ATZ aren't helping. Any ideas?

Ed Vaughn, MBSWWYPBX