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You will need sevral antennas to cover this range.
For the HF range 1-30 MHz you can use a length of wire.
For the other ranges you can make several discone antennas out of stiff wire and a coaxial socket. These cover about a 4-1 frequency ratio range before they start having beam patterns away from the horizon.
EMC test laboratories use a set of antennas for different frequency ranges.
For low they use a caged bow tie with calibration factors for each frequency.
For the mid they use a log periodic with calibration factors for each frequency. For high they use waveguide horns with calibration factors for each frequency. They take the output from the spectrum analyzer and put it into a computer which stores the calibration factors and draws a graph of true signal strength vs frequency.