[A*UG] local at&t pstn/pots AC terminal impedance values

[Ryan Vanderwerf]

Hi, new to the group. I've set up a recent system, and I'm getting a lot of echo on a GXP-2000 phone through a PSTN line at the value of 600R- 600 ohms.
My options are:
600R - 600 ohms</option>
600C - 600 ohms + 2.16uF</option>
900R - 900 ohms</option>
900C - 900 ohms + 2.16uF</option>
COMPLEX1 - 220 ohms + (820 ohms || 115nF)
COMPLEX2 - 270 ohms + (750 ohms || 150nF)
COMPLEX3 - 370 ohms + (620 ohms || 310nF)
COMPLEX4 - 600R 270 ohms + (750 ohms || 150nF)
COMPLEX5 - 320 ohms + (1050 ohms || 230nF)
COMPLEX6 - 350 ohms + (1000 ohms || 210nF)
COMPLEX7 - 200 ohms + (680 ohms || 100nF)
COMPLEX8 - 370 ohms + (820 ohms || 110nF)
COMPLEX9 - 275 ohms + (780 ohms || 115nF)
COMPLEX10 - 120 ohms + (820 ohms || 110nF)

I'm trying to play the the AC terminal impedance values, and I was wondering if anyone knew what value the local Austin area AT&T PSTN/Pots lines use? I figured I'd ask before trying all of them.

Thanks

Ryan Vanderwerf