Microtest TSB-67 - 568A Annex E manual Using Multiple Injectors, Injector Calibration

	Injector
Measurement	Required?	Description
Attenuation	Yes	The Injector generates the frequencies and the Scanner
		measures the signal to determine the signal loss.
Autotest	Yes	The Injector is required for Attenuation, NEXT
		measurements, Resistance and Wire Map during Autotest.
Capacitance	No	If connected, the Injector provides an “OPEN” for the
		duration of the measurement.
Length	No	If connected, the injector provides an “OPEN” for the
		duration of the measurement.
Impedance	No	If connected, the injector provides an “OPEN” for the
		duration of the measurement.
NEXT - Scanner	Yes	The Injector provides a 100 ohm termination while the
End		Scanner measures NEXT.
NEXT - Injector	Yes	The Scanner provides a 100 ohm termination for the
End (2-Way		duration of the measurement.
Injector+/2-Way
Injector only)
Loop Resistance	Yes	If connected, the Injector is used to “SHORT” the wire pair
		under test and the Scanner measures Loop Resistance. If the
		2-Way Injector is not connected, the Scanner will display
		“OVR” (Over Range).
Wire Map (Find	Yes	The Scanner communicates with the Injector across the link
Cable Faults)		under test to determine the wire connection from the
		Scanner end to the Injector end.
Noise	No	The Injector is not required to measure impulse noise or
		peak-to-peak noise.

Note: The Injector is not used when testing coaxial cable. See Appendix D: Working with Coaxial Cable for more information.

Using Multiple Injectors

One Scanner can store calibration data for up to five Injectors. To determine which Injector is attached to the Scanner, press the Extended Functions key, then select Injector Info. The Scanner will display the serial number and other information for the attached Injector.

Injector Calibration

Calibration of the Injector’s signal amplitude is required for accurate Attenuation measurements and requires user intervention. To maintain accurate Attenuation measurements, the Injector must