Service

Service

Service instructions consist of principles of operation, troubleshooting, and repairs.

Principles of Operation

The A1 Bulkhead assembly on the Agilent E-series E9300 power sensors provides a 50 ohm load to the RF signal applied to the power sensor. The A1 Bulkhead assembly on the E9300/1B sensors includes a 30 dB attenuator that can be disconnected by means of a Type-N connector. The A1 Bulkhead assembly on the E9300/1H sensors includes a 10 dB attenuator in the front end. A dual range GaAs diode pair/attenuator/diode pair assembly in the bulkhead rectifies the applied RF to produce dc voltages (high and low ranges) which vary with the RF power across the 50 ohm load. Thus the voltage varies with the RF power dissipated in the load.

The low-level dc voltages from the bulkhead assembly are amplified before they are transferred on standard cables to the power meter. The amplification is provided by an input amplifier assembly which consists of a chopper (sampling gate) and an input amplifier. The chopper circuit converts the dc voltages to ac voltages. The chopper is controlled by a 220 Hz square wave generated by the power meter. The amplitude of the sampling gate output is a 220 Hz square wave which varies with the RF power input. The 220 Hz ac output is applied to an amplifier which provides the input to the power meter.

The Agilent EPM series power meter automatically detects when an Agilent E-series E9300 power sensor is connected and downloads the correction data from the sensor’s EEPROM. In the E9300/1B/H the EEPROM contains an offset value for the measured attenuation value of the attenuator used in the bulkhead assembly. Thus, the attenuator is matched to a particular sensor. The auto-averaging settings are also configured automatically for use with Agilent E-series E9300 power sensors. This configures the power meter to operate over the range with that particular sensor’s unique correction data applied.

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Agilent Technologies E9300 manual Service, Principles of Operation