James Harper wrote on Saturday, 14 January 2006 3:17 PM: >> Are the AU telephone standards the same as US standards (eg, 600 ohm >> impedence)? > > This is a question I've been trying to answer too. I had a look at > the standard phone that Telstra would provide to customers about 5 > years ago, and it has an impedence switch on the bottom to toggle > between 'NORM' and '600', which suggests that 600 ohms isn't the > normal impedence. > > On an au configuration example for the pap2 I have seen on the web, > the impedence is set to '220+820||120nF', which suggests that our > standard here isn't 600.
Indeed, the AU standard is just what you quoted. It is complex impedance. A 220-ohm resistive load connected in series to an 820-ohm resistive load which is connected in parallel with a 120nF cap. >>> Does anyone know of an addon device which can do impedence matching >>> on the line, or of a modification to the > card I don't know if this will help you, but you may do a Google search for the ETAL P3324 and P3356. I believe they may handle the impedance matching you need. Here is a link to a PDF spec sheets: http://www.ibselectronics.com/pdf/pa/etal/line_P3324.pdf http://www.ibselectronics.com/pdf/pa/etal/line_P3356.pdf -- Trevor Hammonds _______________________________________________ --Bandwidth and Colocation provided by Easynews.com -- Asterisk-Users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users
