Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!accuvax.nwu.edu!nucsrl!telecom-request From: John Higdon Newsgroups: comp.dcom.telecom Subject: Re: What Would it Take For Modems to Recognize Call Waiting? Message-ID: <11654@accuvax.nwu.edu> Date: 3 Sep 90 08:51:40 GMT Sender: news@accuvax.nwu.edu Reply-To: John Higdon Organization: Green Hills and Cows Lines: 73 Approved: Telecom@eecs.nwu.edu X-Submissions-To: telecom@eecs.nwu.edu X-Administrivia-To: telecom-request@eecs.nwu.edu X-Telecom-Digest: Volume 10, Issue 616, Message 1 of 8 Craig Jackson drilex1 writes: > One time during a football game, the coverage was interrupted partway > through the game. > So at least in this case, the 'equipment problem' was real. I don't > know if any monetary relief was in order due to the interruption. But > I'm pretty sure that the TELCO has themselves covered so they don't > have to fork out, or forgo charges, when a call runs so long that it > causes equipment failure. With the rapidly advancing cost of equalized lines, most broadcasters have been looking to other methods of carrying program material in both temporary and permanent situations. Most radio stations now use 950 MHz equipment to carry program to the transmitter. But for remote broadcasts, there are a number of options. With the advent of frequency agile, wideband 450 MHz equipment, and large number of broadcasters are turning to the airwaves to solve their remote broadcast woes. Unfortunately, in major metro areas the available frequencies for 450 MHz remote use are scarce. Even with coordinating committees, the scramble for channels frightens many away. A semi-popular alternative is to use a dial up telephone line with a "frequency extender". This device operates under the assumption that what makes a phone line sound bad is the lack of low (yes -- low) frequency response. To correct this, the audio channel is shifted up about 500 Hz. That would mean that a tone of 1000 Hz would travel over the phone line as 1500 Hz. It would also mean that a sound occurring around 50 Hz would travel as 550 Hz, well within the response capability of any phone line. There are also multi-line models that split the band up into parts and send 3000 Hz wide "slices" over each line. Obviously, there is appropriate decoding equipment at the receiving end in all cases. I am personally unimpressed by these devices and feel that if a broadcast is going to travel over a dialup line, it might as well go barefoot for all the improvement you get with "frequency extenders". One of my clients just bites the bullet and buys 8 KHz and 15 KHz dedicated lines and builds them into the cost of the remote as billed to the advertiser. A good telco equalized line is still the champ when it comes to quality -- even over wideband 450 MHz equipment. With the amount that they spend with Pac*Bell (they do MANY remotes), they have been provided with a virtually permanent on-site installer. The service with those lines has been VERY reliable and they sound VERY good. Which brings us to the question about telco liability for service interuptions on dialup. Most tariffs call for a credit of one day's worth of the monthly service charge for each day that the service is unusable after the first 24 hours of service loss. So for the lost call, there would be no liability whatsoever. Only if no calls could be made for at least the next 24 hours would there be any remuneration from telco. And that would be minimal. John Higdon | P. O. Box 7648 | +1 408 723 1395 john@bovine.ati.com | San Jose, CA 95150 | M o o ! [Moderator's Note: His message and your response reminds me of years ago when once a week I would see a very large truck parked in the alley behind Orchestra Hall on Michigan Avenue. The truck was inscribed "Illinois Bell Telephone Co". A large cable coming out the stage door of Orchestra Hall ran into the back of this truck. Then it came out of the truck, and down into a manhole nearby. The weekly broadcast of the Chicago Symphony Orchestra to how many ever radio stations carried it started out at that point. This would have been the early 1950's; I was around ten years old, and fascinated by the inside of the truck, and the fellow who worked inside backstage wearing an operator's headset into which it seemed he was constantly talking to someone, somewhere. PAT]