Sec/Div Switch - Tektronix 2212 User Manual

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SEC/DIV Switch
5-18
With the SEC/DIV switch you may select calibrated sweep
rates in a 1-2-5 sequence in the Store and Non-Store mode.
The resp. selection ranges are :
- 50 s per division to 20 µs per division in Store mode.
- 0.5 s per division to 0.05 µs per division in Non-Store
mode.
- Two External Clock modes (EXT CLK) can be selected
(in Store mode only) on the fully counterclockwise part
of the SEC/DIV switch range, respectively:
• ROLL mode (external clock frequencies of
DC-4kHz)
• RECORD mode (external clock frequencies of
DC-10 MHz)
In X-Y Store mode, the sampling rate can be established in
two ways:
• The internal clock, set by the SEC/DIV switch
• An external clock signal applied to the EXT CLK input
In Store mode, the SEC/DIV switch setting determines the
acquisition and display modes, also sets the sampling rate
and establishes the time scale factor of the displayed wave-
forms. There are two storage modes with respect to the
SEC/DIV switch setting (see also Table 5-2):
- RECORD mode - In RECORD mode, the acquired
waveform updates a full record each time a trigger
event is recognized.
The storage mode is RECORD at sweep speeds of 20 µs
to 50 ms per division.
- ROLL mode - In ROLL mode, the waveform is ac-
quired and displayed continuously. Triggers are
disabled except in SGL SWP (single sweep). The
waveform display scrolls from right to left across
thecrt screen with the latest samples appearing at
the right edge of the crt.
The storage mode changes automatically to ROLL at
sweep speeds of 0.1 s per division to 50 s per division.
In Detail