A.H. Systems AK-2G Antenna Kit
A.H. Systems inc. – January 2007
REV B
8
ANTENNA FORMULAS AND CALCULATIONS
E-FIELD ANTENNAS
Add antenna factor plus cable loss to receiver reading in dBuV to convert to field
strength in dBuV/meter.
Field Strength(dBuV/m) = SA(dBuV) + AF(dB) + cable loss (dB)
LOOP ANTENNA
dBpT = dBuV + dBpT/uV + Cable Loss
dBuV/m = dBpT + 49.5 dB
BROADBAND CURRENT PROBES
A specific Transfer Impedance Factor is associated with each frequency. This number is
to be subtracted from the receiver reading in order to convert to dBuA
dB
A = dB
V (from Receiver) - Transfer Impedance (dB
) - cable Loss (dB)
EXAMPLE:
Assume that the frequency of interest is 80 KHz and we need to find the current at this
frequency. Connect the probe per figure 1
Frequency: 80 KHz
Transfer Impedance: -2.76 dB ohms
Cable Loss: 0.1dB
Receiver Reading: -33.0dBuV
dB
A = dB
V (from Receiver) - Transfer Impedance (dB
) - cable Loss (dB)
dB
A
= -33.0 - (-2.76) - - 0.1
dB
A
= -30.14
