 | REF LEVEL The reference level is the top graticule line on the measurement display. If the reference level offset is not zero, the offset reference level is displayed at this location. Selecting the plus (+) or minus (–) control increments the value by 10. The plus/minus (+/-) button on the keypad toggles between positive and negative values. AUTO REF LEVEL Auto reference level automatically adjusts the reference level to place the highest signal amplitude at about two graticule lines from the top based on the position of the trace at the time the button is pressed. SCALE/DIV The scale can be set from 1 dB per division to 15 dB per division. The default setting is 10 dB. Selecting the plus (+) or minus (–) control changes the value by 1. SCALE/DIV is not available when linear y-axis amplitude units are selected. Y AXIS UNIT Selects the y-axis amplitude units. Available units are: Logarithmic: • Channel Scanner measurements: dBm (default), dBW, dBV, dBmV, dBµV, or dBA • Field strength measurements: dBm/m2, dBW/m2, dBV/m, dBmV/m, dBµV/m Linear: • Channel Scanner measurements: Volt (scalable to V, mV, µV, nV), Watt (scalable to W, mW, µW, nW, pW, fW), and A (scalable to A, mA, µA, nA) • Field strength measurements: V/m, W/m2, W/cm2, A/m REF LEVEL OFFSET Reference level offset compensates for the presence of external input attenuation or gain. The offset is applied to all amplitude related parameters and to measurements such as the y-axis scale and marker measurements. The default offset value is 0 dB and will always be presented in dB units. Selecting the plus (+) or minus (–) control increments the value by 10. The plus/minus (+/-) button on the keypad toggles between positive and negative values. PRE AMP Turns the low-noise front-end preamplifier on or off. To ensure accurate measurement results, the largest signal into the instrument input when the preamplifier is turned on should be less than –40 dBm. The preamplifier cannot be turned on if auto attenuation is on and the reference level is above –40 dBm. AUTO ATTEN Input attenuation can be either tied to the reference level (on) or manually selected (off). When input attenuation is tied to the reference level, attenuation is increased as higher reference levels are selected to make sure the instrument input circuits are not saturated by large signals that are likely to be present when high reference levels are required. ATTEN LEVEL When auto attenuation is off, the attenuation value can be set manually to a resolution of 5 dB. Selecting the plus (+) or minus (–) control increments the value by 5. FIELD STRENGTH Refer to SPA measurement guide (10580-00447) for a description of the measurement. IMPEDANCE This functionality is not applicable to channel scanner measurements. CUSTOM IMP LOSS This functionality is not applicable to channel scanner measurements. |