Textron Greenlee Communications DataScout 10G, User Manual

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68 4-Wire Noise Measurements
Wideband:
►
E (DSL)
►
F (HDSL)
►
G (ADSL)
Tap the noise pull-down menu to select the desired noise measurement filter. When in
voiceband mode only the voiceband filters will be displayed and in wideband only
wideband filters.
Noise-to-Ground does not require an external cable and shorts Tip/Ring and measures
across T/R to ground, typically through a C-Message filter and displays results in
dBrnC.
Impulse Noise
For Impulse noise use the threshold pull down to set the Low (29 to 84) threshold. The
Mid, and High levels are set based on the Low threshold setting. The test set counts to
9999 and displays OLF if the counter is greater than 9999 counts. Under the counts
you will find the Clear Impulse counter button. The elapsed time will restart when the
Clear button is pressed.
Dropouts, Gain & Phase Hits Amplitude Jitter & Phase Jitter
A dropout (Figure 5-1) is counted when the level of the holding tone decreases by at
least 12dB+/-1dB whereas gain hits (Figure 5-2) are counted when a change in ampli-
tude of the holding tone exceeds a preset threshold which may indicate an increase or