Voltech AT360, Руководство пользователя

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V
OLTECH
AT
I
U
SER
M
ANUAL
P
AGE
7-97
The return loss is calculated using the formula:
RLOS = 20 log
10
(

Z
O
+ Z
M

/

Z
O
– Z
M

)
Where Z is a complex impedance in the form Z= R + jX
Or:
Where:
Ro
is the resistive portion of the reference impedance
Rm
is the resistive portion of the measured device’s impedance
Xo
is the reactive portion of the reference impedance
Xm
is the reactive portion of the measured device’s impedance
Choosing Test Conditions
The voltage and frequency are usually determined by the final application of
the part under test. 1000Hz is typical for the mid band of audio
telecommunications circuits.
½
( R
o
- R
m
) + ( X
o
- X
m
)
r = 20 log
10
( R
o
+ R
m
) + ( X
o
+ X
m
)
2 2
2 2