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INSTRUCTION MANUAL
AM-741R
ACTIVE MONOPOLE ANTENNA
1912 1 E l T o ro R d
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Si l vera do, Ca lifo rni a 9 26 76
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(9 49) 459 -96 00
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co m-p o wer. com
REV112216
4.1 Antenna
Factors
Your AM-741R Active Monopole Antenna is provided with frequency-specific
antenna factors, which must be added to the measured value to determine the
field strength value.
Meter Reading (dBuV) + Active Ant. Factor (dB/m) = Electric Field Strength (dBuV/m)
4.2 Preamplifier
Gain
Factors
Our second category of correction factors are gain factors for preamplifiers.
Preamplifiers are used to increase measurement sensitivity by increasing signal to
noise ratio. This is necessary when measuring low signal levels which would
otherwise be buried below the inherent noise floor of the measuring instrument,
typically a spectrum analyzer or EMI receiver. Ideally, input signals levels are
increased proportionate to the preamp’s gain, without significantly increasing the
overall system noise level.
The AM-741R is an Active Monopole Antenna, and contains an internal
preamplifier, so additional signal amplification should not be needed.
Additionally, the preamplifier gain values are included in the antenna factor, so
no additional measurement correction is necessary.
4.3 Insertion Loss Factors
As discussed previously, our third category of correction factors is insertion loss
factors. These factors can include the insertion loss values of coaxial cables,
band-pass or notch filters, attenuation pads, connecting adapters, etc. Basically,
it includes any measurement system component (cable, adapter, combiner,
divider or any other device) installed in-line with your measurement path having
inherent insertion loss over the frequency range of the measurements,
intentionally or unintentionally, beyond that which is considered to be negligible.
If the exact insertion loss factors (or values) are unknown for one or more
component(s) of your measurement system, refer to section 4.3.1.
Insertion loss factors (or values) must be added to the measured values in order to
obtain the ‘corrected’ values.
