Vf Loss Test; Setting Up A Vf Loss Test - Test Equipment Depot 990DSL User Manual

990DSL
Users Guide
Metallic coupling due to power line crosses will exhibit a high fundamental
content, but will have little or no harmonic frequency content.
Coupling due to AC current in the cable sheath, caused primarily by large
earth return currents from unbalanced 3-phase power lines, will exhibit high
fundamental content as well as both odd and even harmonics.
Press A( ) to view changing harmonics in real-time.
Continuous Harmonics

VF Loss Test

The VF Loss test requires that a manually-controlled VF transmitting device
(such as another CopperPro or the C9925BLT) be connected at the far end of
the pair. The device must be capable of transmitting single tones at a level of 0
dBm at 600Ω. The CopperPro measures the signal level at the near end and
translates it into dB of insertion loss, assuming a 0 dBm transmit level.

Setting Up a VF Loss Test

To set up a VF Loss test, follow the instructions under "Displaying a Setup
Menu" in Chapter 3. Table 4-8 describes the one setup parameter for the test.
Table 4-8. VF Loss Setup Parameter
Parameter Settings (default in bold)
600 Ω or 900 Ω
Termination Impedance
4-44