At 2002-09-18 06:43 -0800, Elbert Smit wrote: >> You could try calling: 050-5222263 or 06-0401 >> (perhaps that's now: 0906-0401?). In any case, >> you shouldn't contact a commercial department, >> but a technical department. > >Are these phonenumbers of technical departments?
The first one is the ordering telephone number for the book: 'Algemene technische eisen voor randapparatuur bestemd voor aansluiting op de telecommunicatie-infrastructuur', voor de telefoondienst serie T11: Hoofddirectie Telecommunicatie en Post (HDTP), Bureau Toelating Randapparatuur. The second one is from 'Account Management Infastructuur' (AMIS) and will connect you automatically to the department of the PTT district you're calling from. But since these telephone numbers are from the book of 1991 they're probably outdated. I assumed however that when you would call them, the people on the other end of the line would be able to tell you more. Even if you would just get a receptionist or concierge you could ask him to look in the internal telephone book, that most large organisations have. >> Perhaps you could also figure out the maximum level >> by studying the ISDN PCM norm, of which the A-Law >> version is used in Europe. Consider that 56kbit/s >> modems use the 65536 voltage levels of the signal >> to code their data. >> >> We used to detect call-progress states by counting >> the number of times that a signal went through the >> zero-level, which is quite easy to detect without >> having to input and analyze the signal through >> an ADC. I should still have the source code. > >I've used a laptop with soundcard and a high impedance connection to the >phonelines to record the modem connections. If you use a sound-edit program >like Cooledit2000 with a spectral view, you can see DTMF-tones, calling >tones, answer tones, measure tone lengths, frequencies, etc. > >I got this tip from a KPN-technician. Very nice and cheap tool, when you >already have a laptop of course ;-) Does it have to be a laptop? Desktops should also be galvanicaly seperated from the mains, I would think. >So far, it gave a lot of information about the connections and solved some >problems, but not all. In my time there used to be a lot of different protocols still active at the PTT-side. There were exchanges from several manufacturers and eras. Currently it's probably all ISDN-based and from the last ten years, but in those days the exchanges could be much older. We had a very old exchange in the old centre of Delft that tended to blow up our bought (EUCLI) interfaces. After a while we decided to design those interfaces ourselves, because we only needed part of the telephone interface functionality. Anyway, only looking at the interface of that particular exchange wasn't enough and also not representative. Greetings, Jaap -- Author: Jaap van Ganswijk INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
