macy@fmsystm.UUCP (Macy Hallock) (07/20/89)
In article <945@gould.doc.ic.ac.uk> cdsm@doc.ic.ac.uk (Chris Moss) writes: > >I saw one advert for a switch which I gather is called a fax switch which >is connected directly to a telephone circuit and allows you to plug in > 1. A Fax machine > 2. A modem > 3. An answering machine As an interconnect company, we install several types of telephone systems and often are called upon to connect customer fax machines into lines also used for voice. Occasionally the same need is expressed for a modem. We have seen several types of fax line switches. They seem to fall into three basic catagories: 1. Manual incoming transfer, with shared ougoing traffic. These rely on a human to answer the line, and push a button, usually hardwired to the tranfer box, which transfers the line and generates a burtst of ringing voltage to start up the fax. Cheap, inconvenient and boring. Viking is one manufacturer that comes to mind. Human often has to recognize CNG tone. Not much better than the early manual faxes, which you pushed "Start" to manually answer the line. 1A. Smae as one, but answering human dials a specified touch tone digit (often 6) several times to initiate the line tarnsfer. Better than 1, but not by much. How do receive fax messages when the office is unattended? 2. Touch tone initiated transfer by originating fax. The cheap units generate a tone to indicate line answer and start dial (one I saw gave a dial tone). Better one have a synthesized voice "Please touch one to send a fax, touch two to tak to someone, etc" These often will default to ring the fax line if no tone is detected, to accomodate incoming faxes from auto-dailing machines (one I saw even detected CNG tones) These we can live with, but only if the thing has a reasonably senstive touch tone detector circuit, and the customer plugs the right cords into the right jacks. 3. CNG detecting incoming units, with touch tone manual transfer. Usually these answer the phone and generate a simulated ringback tone while looking for CNG tones from an autodialing fax. If tone is detected, then the fax line is rung, else the voice line is rung after two ringbacks. These are OK, if they are carefully explained to the customer. I have used one of these with my answering machine at home, and for voice answering as well. If a customer asks us to sell and install a unit, this is what we use. The model we provide is the Fax LineShare. Of course, the human can use touch tones to transfer a manual fax call to the fax. We also sell automated attendants, and have set several of these to transfer calls to modems and faxes. Operation is similar to 2. above, but transfer is by extension number (automated attendants work best behind PBX's). In Europe, most modems are required to generate a guard tone (often 550hz) during dialing and setup. This can be turned on on many modems in the US (its on my Hayes, Prometheus, and Telebit modems, plus one of my generic clone modems (S91 on the Telebit, &G1,&G2 on Hayes) This can be used for modem transfer in some situations. One PBX operator I know has been trained to transfer any call she gets with a guard tone to their modem. (She also does this to the Heavy Breather type calls she gets, betch'a it cleans out their ears!) Command Communications makes a unit that operates like 2 above, that may be able to recognize guard tones (they are in Colorado I think, E-mail me if you need more precise info) A Watson voice managment system (uses a PC with a voice processing card) can do 2. and./or an automated attendant application. (Natural Microsystems - see ads in PC Mag, reviewed as a voice mail system a few months ago, too, in PC Mag) I have one of these on my desk. Neat to program with (You need Watson VIS version, plus some interface software in order to get really custom, though) I am unable to answer UK realted application questions asked by Chris Moss, so CCITT and all that will have to answered by others or the manufacturers (Hah!). Sorry for using all the Net bandwidth, but I hope this will help many of you, judging by past net comments. I will try and answer all E-mail promptly, time permitting. PLEASE E-MAIL TO THE ADDRESSES BELOW ONLY! Other paths may not be reliable. Regards to all, Macy Hallock fmsystm!macy@NCoast.ORG F M Systems, Inc. hal!ncoast!fmsystm!macy 150 Highland Dr. uunet!aablue!fmsystm!macy Medina, OH 44256 Voice: 216-723-3000 X251 Disclaimer: My advice is worth what you paid for it. Your milage may vary.