Tektronix SDA601, Руководство по обслуживанию

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Operating Information
SDA 601 Serial Digital Analyzer 2- 21
A fourth display mode, Review, may be invoked with the
Review
key only. The
four display modes are explained in the next few paragraphs.
Figure 2- 14: The Display Mode Selection Keys
SLM Display Mode.
The SDA601 displays the relative level of the serial digital
input signal when you press the
SLM (A)
key, or toggle “Disp Sig Level” On
through the
Display Select
key/menu. The display will resemble Figure 2--15; note
that a longer “bar” indicates a weaker signal (often due to a longer cable).The
SDA601 SLM can help you identify points in your system where the digital
video signal may be marginal because of long cable runs or faulty equipment.
The signal level display will report an 800 mV
p-p
input signal as approximately
Ø dB (usually, only one segment will be “lighted,” if any).
Figure 2- 15: The SDA601 Signal Level Display
Selecting the Cursor, Time, or Review operating modes with the respective
keys—(
Cursor (B) , Time (F) , or Review (G) —will turn the SLM Off. Reselect the
Signal Level display by pressing the front panel
SLM (A)
key, or—if you want two
or more modes to alternate on the display—toggle the SLM On through the
Display Select
key/menu.
Cursor Display Mode.
The SDA601
Cursor
mode, selected by pressing the
Cursor
(B)
key, makes it possible to locate a single word in the digital video frame and
discover the actual (hexadecimal) value of the selected word and the three words