Operating instructions

OPERATING MANUAL 2945A
46882-311D 3-11
Setup page 1
This page allows the following optional settings to be selected.
RF Counter Resolution 1 Hz/10 Hz
The RF counter resolution can be set to 1 Hz or 10 Hz. Selecting 1 Hz will slow the screen
update rate by a factor of 10:1. The choice is made by toggling between the two options using the
soft key adjacent to the text.
RF Level Measured in Watts/Volts/dBm
The RF level from the transmitter being tested can be displayed in terms of Watts into a 50 ohm
load, voltage across the 50 ohm load or dBm into 50 ohms. The choice would normally be made
so as to match the specification parameter of the transmitter under test. The selection is made by
pressing the soft key adjacent to the text. This will toggle through the three options.
AF Distn/SINAD Averages
When distortion or SINAD tests are made to receivers using the Rx TEST mode or AF TEST
mode, the results displayed are obtained by averaging the results of a number of measurements.
This allows the user to balance the speed of testing against greater repeatability of measurement.
The number of measurements made can be set within the range 1 to 20 by entering the required
figure using the data input keys.
RF Level In: EMF/PD
With the EMF option selected, the displayed RF output level shows the open circuit voltage
available at the RF output connector.
With the PD option selected the displayed RF output level shows the voltage that would be
present across a 50 Ω load.
The selection is made by toggle action of the soft key.
RF Power Ext Atten: dB
The value of any attenuator entered here is considered as part of the instrument and all power
measurements will be as from the input to the attenuator, not to the instrument input. Similarly
power output levels will be adjusted to take account of the external attenuator value entered.
To enter a value of attenuation, which must be in dB, press the adjacent soft key, key in the digits
of the value using the data entry keys and then press the dB terminator key.
The entered value will be applicable to all RF connectors into and out of the monitor. When
changing test setups or test modes this must be taken into account to prevent erroneous readings.
The indicator is shown against any signal level which has been calculated to include the
external attenuator.
Rx=Tx Offset Freq: Hz
A setup option within the Tx TEST mode (Rx=Tx) will set the signal generator used for receiver
testing to the measured frequency of a transmitter being tested. An Rx=Tx offset frequency
entered here will cause the signal generator frequency to differ from the measured transmitter
frequency by the offset frequency. To enter an offset frequency, press the adjacent soft key, key in
the appropriate digits, using the minus key and the decimal point key if necessary, then use the
relevant terminator key, (MHz, kHz or Hz). A positive figure will set the signal generator
frequency above the measured transmitter frequency, while a negative figure will set the signal
generator to a lower frequency than the transmitter.
Return
Returns to the Help/Setup Menu.