NC4796 generates noise simulating near-end crosstalk (NEXT) and far-end crosstalk (FEXT) for production testing of DSL modems. The instrument
contains two independent noise generators, each with continuously controllable
output power from -130 dBm/Hz to -140 dBm/Hz. Using its dual capability, noise can be injected to the modem test circuit for simultaneous testing of NEXT and FEXT. The two outputs are each balanced with output impedance higher than 10 kOhms, which meets the high-impedance crosstalk injection requirements of various T1 standards. The NC4796 may also be used for ADSL, HDSL, as
well as xDSL modem testing.
The high quality Gaussian noise has a crest factor, peak-to-average voltage, larger than 5:1. The controls may be locked and capped for security in unsupervised production environments. Frequency coverage is greater than 50 Hz to 2 MHz with approximately 5 MHz 3 dB bandwidth.
- Output Power Range -130 to -140 dBm/Hz
- Output Power Resolution: Continous
- On/Off Attenuation: minimum 20 dB
- Output Impedance: minium 10 kOhms balanced
- Crest Factor: minimum 5:1