Service
R&S
®
ESH3-Z6
12
Manual 1178.9932.02 ─ 01
5
Service
The V-network R&S
ESH3-Z6 supplies the EUT with power during measurements and
terminates the RFI voltage source of the EUT with a defined equivalent circuit |Z| =
5
µH
//
50
Ω
. Refer to
X2
.
The EUT can be fed with a 100
A continuous current via X1.1, L1, X2.1. C1 and and L1
form a lowpass filter that isolates the EUT and test receiver from interference coming
from the supply network.
The RFI voltage (0.1
MHz to 200
MHz) generated by the EUT is routed via the high-
pass flter C2 and X3 to the test receiver with an input impedance of 50
Ω
.
Attenuation between X2 and X3 is high in the lower frequency range. which is due to
the impedance |Z| of the V-network and the highpass filter action of C2. The source
impedance at X2 is 50
Ω
for this measurement. Attenuation measurements according
to
Chapter 5.2.4, "Voltage Division Factor (VDF) X2 – X3"
serve to check for proper operation of the R&S
ESH3-Z6. Under real measurement
conditions, the source impedance of the EUT is undefined and unknown.
Resistors R2, R6 and R7 discharge capacitors C1 and C2. Resistors R3, R4 and R5
dampen the resonance caused by winding capacitances of the coil.
Block diagram
R&S ESH3-Z6
IF
input filter
AN
artificial network
CC
coupling circuit
X1
Power
source
X2
X3
EUT
Test
receiver
Figure 5-1: Block diagram for R&S
ESH3-Z6
