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Measurement Principles
R&S
®
RT-ZZ80
31
User Manual 1409.7689.02 ─ 02
Fig. 4-9: Input and output signals at an effective source impedance of 25
Ω
To calculate the exact attenuation of the probe, use the following equation:
S
in
in
out
R´
Z
U
U
Ω
50
U
out
: output voltage
U
in
: unloaded input voltage
Z
in
: input impedance of R&S RT-ZZ80
R´
S
: effective source impedance
Example for an 50
Ω
environment:
0952
.
0
Ω
25
Ω
500
Ω
50
in
out
U
U
Attenuation Dependence on Source Impedance