Electro-Metrics EM-2115, Instruction Manual

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ELECTRO-METRICS EM-2115 2.0 OPERATING INSTRUCTIONS
(EM2115S2-28)
For this switch position, the sweep circuitry produces a sweep rate which is ten
(10) times faster than in the CAL position. However, the external X-Y plotter may
not accurately record the amplitude level of a detected signal due to the response
time of the plotter plus the EM-2115 detector and IF bandwidth/Frequency Range
selected. Therefore, the maximum usable sweep speed is dependent on the detec-
tor function, IF bandwidth, and frequency range selected.
NOTE: The required detector setting must be considered when deter-
mining the setting of the Scan Rate Control. Since time is
saved by using the fastest sweep rate that insures an accurate
amplitude recording of a response, the following should be tak-
en into consideration.
1) Peak Detector Mode : The FULL CW (MAX-fastest sweep
rate) position of the Scan Rate Control is normally slow enough
to accurately record the peak amplitude of a response.
2) Quasi-Peak Detector Mode: Mid-range setting of the Scan
Rate Control is normally used to accurately record the ampli-
tude of a response.
3) RMS and AVERAGE DETECTOR MODES: The FULL
CCW (CAL-slowest sweep rate) should be used to accurately
record the amplitude of a response.
e. Set the Scan Mode Switch for the Single Mode of operation. The recorder pen
will be automatically positioned over the left hand margin of the chart paper.
f. Push the Scan Start Switch. This starts the sweep voltage ramp and drops the re-
corder pen.
g. When the sweep voltage reaches the upper frequency limit of the frequency band
range selected, the pen will automatically lift and return to the left hand margin of
the chart paper.
The noise, various slideback levels, and external I.G. levels can be plotted on the chart
paper to produce convenient calibration lines.
2.7 External Oscilloscope Operation
The EM-2115 can produce a spectrum analyzer type display covering the frequency range
of the receiver using an external oscilloscope.
2.7.1 EM-2115 Oscilloscope Output Connectors