Agilent Technologies HP8648A Weather Radio User Manual


 
Using the Spectrum Analyzer
199
Calculate the Field Strength:
13 Calculate Field Strength as follows:
Field Strength (in dBµV) = Signal Level (step 7) + Antenna Factor
For example, (34.98 dBµV) + (+7.4 dB/m) = 42.38 dBµV/m
If Antenna Factor is not known, calculate using Antenna Gain as fol-
lows:
Antenna Factor (50) = 20 log freq (MHz) Gain (db) 29.8dB
Antenna Factor (75) = 20 log freq (MHz) Gain (db) 31.5dB
For example, Ant Factor = 20 log 144.68 6db 29.8 dB = 7.4 dB/m
Convert Field Strength from dBµV/m to µV/m as follows:
Field Strength (in µV/m) = 10 (Field Strength in dBµV/m)/20
For example, 10 (42.38 dBµ]V/m)/20 = 131.52 µV/m