This file is the result of downloading a message board thread relating to telephone service, and is presented here for general information. #: 80934 S4/Tech Notes & Util. 04-Jun-85 21:23:38 Sb: #M100 mic connect Fm: Marty 70007,2246 To: All tech types Over the course of a trip I just took to Chicago and New York, I noted some ideosyncrasies related to the technique of hooking the direct connect cable of a Model 100 to the contacts of the microphone part of a telephone handset. As has been noted years back in the data base here, unscrewing the microphone part of a telephone handset and hooking in the M100 direct connect cable using alligator or similar clips affords a convenient way to make a direct connection to, say, a hotel telephone which does not use accessible modular connectors. I tested this techique out at my house prior to my trip and it worked flawlessly. When I got to the Hyatt in Woodside, Chicago, I tried the same technique. Curiously, I got a LOUSEY connection... garbage kept creeping in to the data. It was utterly unuseable. I tried it four times and had the same problem. Then I whipped out my trusty swiss army knife and unscrewed the telephone set and hooked my clips directly to the incoming red and green wires inside the telephone unit itself. This TOTALLY cured the problem. Later, in Queens, New York, I found that clipping in to the microphone contacts worked flawlessly. I'm not sure why in one place the technique worked and in another it was useless... it mnight releate to ideosyncrasies of the switching system used by the hotel... but I wanted to share these observations with those here. Between the clip in to the microphone contacts and clip in to the incoming phone wires of a disassembled phone, I can now make direct conection to all except public pay phones. Thus, my need for those expensive, bulky, heavy, and easily damaged acoustic cups is very limited. ---Marty 70007,2246 * Reply: Fm: Asysop Tony Anderson 70506,1261 Well, your msg is a typical report of the kinds of problems inherent in using telephone services from unknown systems, and in unknown locations. As such, it's a valuable contribution to the literature. But if you're looking for an explanation, you've come to the wrong party. In the case of the Hilton, remember many of the phone systems in large industrial or commercial installations are installed by the lowest bidder. (read "cheapest") I had occassion to work with the phone systems at the MGM Grand in Reno, NV., and while it was generally a good system, it was erratic. What with todays proliferation of odd-ball and bastardized equipment installations, it's impractical to assume the same technique will work every time, in every location. You just have to try, and find what will work every time you find one of these unknown systems. Personally, I would always prefer going into the incoming line wires, rather than in going into the instrument. With many of the new instruments, made in foreign countries, with parts of unknown quality, you just don't know what to expect. There was an article I read once, perhaps it was in one of the files here, I'll have to check; but it suggested a "kit" for those who often had to rely on telephone systems, or equipment, or unknown origin, quality, or service. The kit included modular cords, adapters, screwdriver, clips, etc.; all the little things you might need to get connected to unusual phone services. Acoustic cups was considered a final alternative, if nothing else worked. I have a similar phone kit, but it includes a linemans handset, tone dialers, modular and four-prong connectors, isolation transformers, amplifiers, lots of adapters, and a notch filter. I have never yet found a phone system I could not get into. * Replies: Fm: William Calvin 71256,1353 What we need is a good induction coil arrangement (that would get around the Tip/Ring separation problem). Fm: Asysop Tony Anderson 70506,1261 There have been induction coils for use with telephone recorders and other other such uses for years, where one needs to recover audio from the phone line. There once was one shaped like a ring that fit around the earpiece, and you could send audio both ways with it, ie either recording from the phone, or sending taped messages into the phone. There was also one that attached to the side of the phone base, next to the transformer in the phone, and inductively coupled the audio into a recorder. I still think the "kit" idea, with adapters, modular cords, clips and a screwdriver, to be the most effective, and it's available now! As for tip-ring, when you are connecting to the line, or transferring data, the tip-ring polarities don't matter, you are transferring AC (audio) and the tip-ring protocol is primarily a DC protocol. I recognize that many users who travel, want to keep their "extra" baggage down to a minimum, but we're talking about a hand-full of items in such a kit, that couldn't possibly weight a pound, nor take up as much space as an electric razor in it's case. Ideally, everyone would like to carry something about the size and weight of a wood pencil, that would allow instant connection, no matter what the phone system, and perform reliably, with 100% efficiency from anywhere in the world. Sadly, the world's phone systems won't work that way. The only one who ever had such a device was Napoleon Solo, and it only worked on "Channel D". ("Open Channel D") Fm: Marty 70007,2246 That suggestion to put together a fewe useful tools and plugs of the trade into a little bundle for on the road use is a really good one... I was sorta beginning to do that by default myself in that last trip (the first trip I took since getting the M100 a month ago). Thanks very much for the suggestion. I already was carrying my swiss army knife, a female to female modular adaptor, the M100 direct cable, and a male modular to alligator clips cable. That was fully adequate for that last trip, as my note implied. But now I think I'll get together a more formal, packaged bag of those tricks, and maybe one or two other items (four prong connector and some other stuff). I left that note as a novice M100 user, just to share what appeared to me to be s somewhat puzzling experience. Thanks again for your very long and thorough reply!!! ---Marty For those interested in tips on connecting into the phone system, I suggest you read the files CLIPS.HLP and CLIPS2.HLP in DL7, the first uploaded by Tim Ekdom, and the second by Michael A. Lampert.