Freedom R8100 SERIES, Operator'S Manual

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Available when Select Voltmeter Mode is AC Volts and a reference input voltage is not set. When
selected, dBm measurements are frozen and a dBr indicator appears. The dBr indicates the normalized
measurement between the reference input voltage and the current input voltage.
Clear dBr Reference
Available when Select Voltmeter Mode is AC Volts and a reference input voltage is set. When selected,
dBm measurements are resumed and the dBr indicator disappears.
DC Range
Available when Select Voltmeter Mode is DC Volts. Choices include Auto (auto-ranging), 1 Volt, 10
Volts, 100 Volts and the Battery voltage when that upcoming option is installed. Note: The range on AC
and DC must be 1 or 10 Volts to use 600 Ohm Input Impedance (see System Settings).
2.2.5.3 SINAD/Distortion
Provides Signal in Noise and Distortion (SINAD) and audio distortion measurements for a radio under
test – see Figure 2.2.5.3-1.
Figure 2.2.5.3-1 SINAD display
Select Audio Measurement
Choose SINAD/Ext Distortion or Internal Distortion on a horizontal menu.
SINAD/Ext Distortion – Provides a SINAD and External Distortion measurement of the recovered audio
signal applied to the Meter In port from an external radio (Figure 2.2.5.3-1). The test is performed using
a 1 kHz modulated RF carrier applied to the radio’s antenna port by the R8100. The RF level is adjusted
in the RF Zone while monitoring the SINAD meter to determine the receiver sensitivity per EIA (12 dB
yellow tick mark) and other standards (See SINAD Measurement).
Internal Distortion – Measures the distortion in percent of the internally recovered audio from a transmitter
modulated with a 1 kHz sine wave when the R8100 is in Monitor mode (Figure 2.2.5.3-2).
Figure 2.2.5.3-2 Internal Distortion display
2.2.5.4 Decoder
This is the entry point for the suite of tone decoding functions on the R8100
Select Decoder Type