Tektronix SPECMON3 Manual page 80

General Signal Viewing
4. If you select +Peak Trace or -Peak Trace, use the Function drop-down list to select either Normal or
Hold.
a. Select Normal to set the trace to display the maximum/minimum values acquired in each
individual update.
b. Select Hold to set the trace to display the maximum/minimum values acquired over time. The
trace values are updated only if they exceed the existing values.
5. If you select Avg (VRMS) or Avg (of logs), use the Function drop-down list to select either Normal,
Average (VRMS), or Avg (of logs).
a. Select Normal to set the trace to display the average values acquired in each update.
b. Select Average (VRMS) or Avg (of logs) to set the trace to display an average of the average
values. Use the Count box to enter the number of times the trace is averaged.
Available Traces for Display (Instruments with Option 200)
Five traces can be shown in the DPX Spectrum, Zero Span, Frequency, and Phase displays– one bitmap
and four line traces. The default traces are Bitmap and Trace 1. The other three traces are 2, 3, and Math.
Line traces 1, 2, and 3 have user-selectable Detection and Function settings. The final line trace is Math,
allowing you to subtract one line trace from another.
For the DPXogram display, only one trace is available — the DPXogram trace.
For the Split display, which consists of a DPXogram display on the top half and a DPX Spectrum display
on the bottom half, you can display the Bitmap trace, Trace 1, Trace 2, Trace 3, Math trace, and Ogram
Line (the selected line from the DPXogram display) on the bottom half of the display.
Selecting Traces for Display (Instruments with Option 200)
This is done almost the same as with the standard instrument, except that the choices available for Trace
are different. Instead of +Pk, –Pk, and Avg traces, you select Trace 1, 2, and 3 and independently set the
Detection method for each of these traces to +Pk, -Pk, Avg (VRMS), or Avg (of logs).
Reference.
Changing the DPX Spectrum Display Settings (see page 270)
Tx BER Testing in the DPX Frequency View
The Transmit Bit Error Rate Testing (Tx BER) function measures the bit error rate in a data stream
modulated on a carrier. The modulation type supported is a 2-level FSK signal (2FSK) with a symbol rate
of 16 kHz. Tx BER is available only in the DPX Frequency plot.
The Center Frequency must be set to the carrier frequency. The RBW or Measurement BW must be set
high enough to pass the full frequency deviation of the modulated signal. The vertical scaling on the
display does not affect the measurement. The measurement is also unaffected by trigger settings.
The 16k symbol/second rate has a tolerance of ±10ppm. The data patterns supported are PRBS-9,
PRBS-11, PRBS-15, and User.
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SPECMON3 & SPECMON6 Printable Help
DPX Display