Electro-Metrics EM-2115, Instruction Manual

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ELECTRO-METRICS EM-2115 1.0 INTRODUCTION/SPECIFICATIONS
(EM2115S1-1)
SECTION I
EM-2115
INTRODUCTION AND SPECIFICATIONS
1.1 Introduction
The EM-2115 Interference Analyzer performs emission and susceptibility testing to MIL-
STD-461 and MIL-STD-462, CISPR, plus other applicable military, government, and commer-
cial (both domestic and international) standards from 9 kHz to 1000 MHz.
A built-in microprocessor controls the operation of the receiver through information
keyed in by the front panel controls. In addition, front panel controls are directly accessible from
a computer through the IEEE-488 General Purpose Interface Bus (GPIB).
LED displays provide accurate readings of tuned frequency and signal strength. The fre-
quency measurement is accurate to ±0.1% and the amplitude measurement, which includes atten-
uation, is accurate to ±2 dB. Separate LED displays enhance the main displays indicating the fre-
quency range in use and the level of attenuation. For ease in tuning, the digital meter is augment-
ed by a front-panel analog meter. In addition, a Beat Frequency Oscillator (BFO) is included to
aid in tuning CW signals.
Advanced detector circuits provide true average, direct peak, quasi-peak, true rms, and
slideback.
a. "True Average" Detector: The "True Average" detector provides the true time-
averaged value of the amplitude of any signals appearing at the RF input that are
within the IF band pass. When used in conjunction with the Peak or RMS Detec-
tors, the modulation of modulated CW signals and the duty cycle of impulsive
signals can be approximated.
b. Direct Peak Detector: The Direct Peak Detector measures the vector sum peak of
the voltage within the selected IF band pass of the receiver. A sample and hold
circuit, having a rise time of less than 2 µs plus an associated dump circuit to reset
the detector for the next peak reading, is used to make the measurement.
c. Quasi-Peak Detector: The Quasi-Peak Detector circuit results in measurements
which conform to ANSI C63.2-1980, CISPR Publication 16, and related VDE re-
quirements.
d. "True Rms" Detector: The "True RMS" detector measures the time-averaged
true rms value of the signal within the selected IF band pass, providing an indica-
tion of the average power at the input of the receiver.
e. Slideback Peak Detector: The Slideback Peak detector is an envelope detector
with the addition of a threshold level control. If more than one broadband signal is
present within the selected IF band pass of the receiver, the peak amplitude of
each signal can be measured using either an aural (audio--headphones) or visual