Transmission Tracking (Etf And Etr) - Agilent Technologies 8719ET Service Manual

Error Terms
Error Term Descriptions

Transmission Tracking (ETF and ETR)

Transmission tracking is the difference between the frequency response of the reference
path (including R input) and the frequency response of the transmission test path
(including A or B input) while measuring transmission. The response of the test port cables
is included. These terms are characterized by measuring the transmission (S21, S12) of the
"thru" configuration during the measurement calibration. Note that coupler response is
included in this error term. Typically, this appears as a roll-off below 500 MHz, which is
typically −18 dB at 100 MHz, and −25 dB at 50 MHz
Significant System Components. Large variations in this error term probably indicate
a problem in the reference signal path (if both ETF and ETR are bad) or in the A or B input
path. The "thru" cable also has an effect on transmission tracking.
Affected Measurements. All transmission measurements are affected by transmission
tracking errors.
Figure 11-6 Typical ETF/ETR
11-16
8719ET/20ET/22ET
8719ES/20ES/22ES
RF Network Analyzers
Service Guide