Atec 9335-2 User Manual

DESCRIPTION

The unique winding arrangement of this imped­ance matching probe* provides step-up or step­down ratios with respect to either: 1) the source
impedance of the connected generator, when
used for injection, or 2) the load impedance of
the connected receiver, when used for reception.
This results in maximum power transfer into
or out of the transformer winding formed by
the cable bundle passing through the window.

The Type 9335-2 Multiple Impedance Coupling
Device provides:

1:1.0 voltage or current transfer
1:1.5 voltage step-up or current step-down
2:1.0 voltage step-down or current step-up
1:3.0 voltage step-up or current step-down

These ratios are selected by connecting to one
of the four BNC connectors on the side of the
Type 9335-2.

Figure 1 shows a family of curves representing the
transfer functions for each connector port when
the device is used as an injection probe.

Through connector port selection, the open
circuit voltage or short circuit current can be
adjusted for maximum transfer of energy. This is
especially useful as an accessory to the Model

9354-1 Universal Transient Pulse Generator

with its differing source impedances, enabling
it to meet various open circuit voltage, and short
circuit current requirements.

CALIBRATION

For proper calibration of current probes,a special
test fixture must be used to maintain a 50 ohm
characteristic impedance for the test signal as it
passes through the window of the probe.

The design of the Type 9357-1 Calibration
Fixture was carefully tailored to provide a 50 ohm
characteristic impedance based on the specific
dimensions of the Type 9335-2.The fixture
maintains a low standing wave ratio from 10 KHz
to 10 MHz in a 50 ohm circuit.

* We refer to this unique device as the Knoller

Probe, since it is the brainchild of Hank Knoller,
an EMC engineer with more than forty years
experience in the design and application of
equipment for EMI testing.

TYPE 9335-2 MULTIPLE IMPEDANCE COUPLING DEVICE

impedance matching injection probe

APPLICATION

Various EMI specifications require the injection
of high level voltage or current pulses and the
reception of low level voltage or current emis­sions using a toroidal transformer or coupling
device around the interconnecting conductors of
the subsystems/equipment being tested.

The Type 9335-2 Multiple Impedance Coupling
Device is a split toroid, designed as a versatile
impedance matching transformer used in conjuc­tion with a generator as an injection probe for
conducted susceptibility tests such as methods
CS10 and CS11 of MIL-STD-462, Notice 5; CS116 of
MIL-STD-462D; DO-160C,Section 22, Figure 22-12;
and other specifications.

INJECTION – High power transient generators
with source impedances from 0.25  to 50 
can use this probe to deliver high peak voltage
or high current pulses into the wires or cables
passing through the window of the device.

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