NARDA PMM 9010 Series, User Manual

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RMS-AVG and C-AVG Detectors A-A-3
A-A.4 C-AVG
Definition
CISPR 16-1-1 defines the Average detector as designed to indicate the
weighted average value of the maximum value of the envelope of the signal
passed through the pre-detector stages:
up to 1000 MHz, is defined as the response of the measuring receiver to
pulses of repetition rate
n Hz and impulse area of 1,4/ n mVs emf at
50 Ω source impedance that shall be equal to the response to an unmodulated
sine-wave signal at the tuned frequency having an emf with rms value of 66
dBµV.
The value of
n shall be 25 for Band A, 500 for Band B, and 5000 for Bands C
and D.
For the frequencies over 1 GHz the value of n shall be 50 000.
The average detector is useful to measure narrowband signals to overcome
problems associated with either modulation content or the presence of
broadband noise.
When the Average is measured according to CISPR 16-1-1, the maximum
value of the linear mean envelope during the measurement interval is
showwn.
The detector is used, for example, to measure pulsed sinusoidal signals with a
low pulse repetition rate. It is calibrated with the rms value of an unmodulated
sinewave signal. Averaging is carried out with lowpass filters of the 2nd order
(simulating a mechanical instrument).
Be sure not to overload PMM 9010: the input signal should not exceed
the maximum level indicated in the main specifications in chapter 1.
Also do not apply any signal to RF generator output connector.