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Thin-Film Directional Couplers
CP0402 / CP0603 High Directivity Couplers Test Jigs
GENERAL DESCRIPTION
These jigs are designed for testing the CP0402 and CP0603
High Directivity Couplers using a Vector Network Analyzer.
They consist of a dielectric substrate, having 50Ω microstrips
as conducting lines and a bottom ground plane located at a
distance of 0.254mm (0.010") from the microstrips.
The substrate used is Neltec’s NH9338ST0254C1BC.
The connectors are SMA type (female), ‘Johnson Components
Inc.’ Product P/N: 142-0701-841.
Both a measurement jig and a calibration jig are provided.
The calibration jig is designed for a full 2-port calibration, and
consists of an open line, short line and through line. LOAD
calibration can be done by a 50Ω SMA termination.
When measuring a component, it can be either soldered or
pressed using a non-metallic stick until all four ports touch
the appropriate pads. Set the VNA to the relevant frequency
band. Connect the VNA using a 10dB attenuator on the jig
terminal connected to port 2. Follow the VNA’s instruction
manual and use the
calibration jig to perform a full 2-Port
calibration in the required bandwidths.
Place the coupler on the measurement jig as follows:
Input (Coupler) ➜ Connector 1 (Jig) Termination (Coupler) ➜ Connector 3 (Jig)
Output (Coupler) ➜ Connector 2 (Jig) Coupling (Coupler) ➜ Connector 4 (Jig)
To measure I. Loss connect:
Connector 1 (Jig) ➜ Port 1 (VNA) Connector 3 (Jig) ➜ 50Ω
Connector 2 (Jig) ➜ Port 2 (VNA) Connector 4 (Jig) ➜ 50Ω
To measure R. Loss and Coupling connect:
Connector 1 (Jig) ➜ Port 1 (VNA) Connector 3 (Jig) ➜ 50Ω
Connector 2 (Jig) ➜ 50Ω Connector 4 (Jig) ➜ Port 2 (VNA)
To measure Isolation connect:
Connector 1 (Jig) ➜ 50Ω Connector 3 (Jig) ➜ 50Ω
Connector 2 (Jig) ➜ Port 1 (VNA) Connector 4 (Jig) ➜ Port 2 (VNA)
MEASUREMENT PROCEDURE
Measurement Jig
Connector 1
Connector 2
Connector 4
Connector 3
Calibration Jig
Short Line
to GND.
Load &
Through
Load &
Through
Connector
Johnson
P/N 142-0701-841
Open
Line
HS
OPEN
TH
