Current Probe Fixture CPF-630

Injection Probe calibration fixtures are a part of the test equipment required by most of the Bulk current Injection Test Procedure Specifications. The Calibration Fixture allows the user to quickly and easily calibrate the injection probe prior to performing the compliance testing. It exceeds DO-160, Section 20 VSWR fixture requirements for stand-alone injection probe calibration fixture.

The test fixture is composed of an electrically short section of trough transmission line. The short section permits the measurement of current in the center conductor of the line, while the current probe is clamped around the center conductor. The fixture's output terminal is terminated in a 50 ohm receiver, spectrum analyzer or RF voltmeter. A measurement of the voltage developed by this RF voltmeter permits the calculation of current flowing in the center conductor. The trough is large enough to permit the current probe to be clamped around the center conductor, with the outer conductor of the trough extending around the current probe's outer shield.

Due to variable circuit impedances or resonances in cables and cable looms, the calibration fixture is used to establish the forward power into the injection probe needed to develop the specified currents in the system under test.