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The DMU is quite often shown in pictures with the FT-2000. Spectrum scope is just one of its many features
A few of its features:
The Yaesu DMU-2000 option provides a wide array of informative and useful displays for the FT-2000 series.
Spectrum Scope with Limited Bandwidth Sweep feature
Audio Scope/Oscilloscope Display Page
Swept-Frequency SWR Page
Memory Channel List
World Clock with GrayLine Page
Rotator Control Page
Log Book Feature
measure collector and bias voltages of final transistors
measure heat sink temps
Please note that this device does require a computer display and computer keyboard (both not supplied).Complete operating manual for the DMU-2000 is available in PDF form on the Yaesu web site.