Hi Rene, Thank you for your response.
I'm very surprised tax pulses are transmitted in such a trashy way. Neglecting zero start or an eponential rise of tax pulses flys in the face of good and reasonable telecom engineering. I you or I did that the PTT's would be down on us very quickly. I don't have much patience with such poor engineering practices. Faced with the stringent telecom requirements of the PTT's in question I have to think this smacks of a double standards. i.e. don't do as I do, do as I say. After 15 years of tough design reviews at Racal-Vadic I guess I've been indoctrinated to use only good analog engineering practices. I would never consider transmitting a signal in such a schlock way. As much as U.S. telecom practices are maligned by engineers and PTT's outside of this country, this kind of signal generation in not allowed. Part 68 is a double edged sword, it also controls the approval of CO equipment. Forced to receive signals transmitted by just slamming them on line places a burden on the back of terminal equipment designers and manufactures. Not to mention the extra cost of proper filtering. If this sounds like sore grapes it is meant to. Regards, Duane _________________________________________ On Thu, 27 Mar 1997, Rene Debets wrote: > Dear Duane, > > As far as I know from working with the Deutsche Bundespost / Deutsche Telekom > the Metering tone is generated by a generator with +- 200 ohms internal > impedance. > Switching it on and off is done (at least in the test setup) by a relay, so > there is > no nice exponential rise, or 0 phase start. Deutsche Telekom procurement lab > claimed that they test it that way because that's how the actual network > works. > > Best regards, Rene >
