Keysight Technologies N432A, User Manual

Page: 106 / 154

2 Operating Information
84 N432A User’s Guide
Figure 2-45 Connection diagram for VRC measurement
8 Measure the S
11
parameter on the network analyzer. The S
11
parameter
is equivalent to the reflection coefficient of the sensor,
Γ
1
. Record the
VRC magnitude of the sensor, |
Γ
1
|, which is an absolute value of the
reflection coefficient.
9 Set the bridge resistance to 100
Ω
by pressing and using the
up/down arrow key to highlight the Bridge Resistance value field. Press
to display the Bridge Resistance pop- up list and use the
up/down arrow key to highlight 100 ohm , then press to enter the
value.
10 Again, measure the S
11
parameter on the network analyzer, which is
now equivalent to
Γ
2
. Record the value of |
Γ
2
|.
11 Set the bridge resistance back to 200
Ω
and power off the N432A.
Disconnect the sensor from the N432A.
12 Now, use a digital voltmeter (DVM) to measure resistance. Connect a
DVM between the N432A rear panel V
RF
output connector and pin 1 on
the thermistor mount end of the sensor cable. Verify that no power is
applied to the N432A.
13 Round off the DVM reading to two decimal places. Record this value as
the first internal bridge resistance, R
1
, of the N432A.
14 Power on the N432A and set the bridge resistance to 100
Ω
. Then,
power off the N432A.
15 Round off the DVM reading to two decimal places. Record this value as
the second internal bridge resistance, R
2
, of the N432A.
N432A
Thermistor
sensor
A
Network analyzer