Tektronix 2715, Руководство пользователя

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Dedicated Controls
2715 User Manual
4–7
Keypad Entry. For very large frequency changes, or to preset a known center or
start frequency, the direct entry mode is faster. To set the center or start frequency
to a predetermined value, do the following steps:
11. Press [CHAN/FREQ] to place the center or start frequency in the immediate
entry mode.
Even though the word CHAN appears at left center of the 2715 screen, you can
enter the center frequency directly from the keypad (immediate entry mode) by
keying in a permissible value followed by an appropriate terminator key ([X],
[Y], or [Z]). You can enter any value from 0 Hz to 1800 MHz, even though the
2715 low-frequency specification is 9 kHz. Your entry can contain up to 25
characters, but regardless of how many you enter, the 2715 attempts to control
frequency to the nearest hertz. The frequency is displayed at the top of the
left-hand data column to 1% of the span/div.
12. Press [1] [ ] [2] [5] [X] to set the center frequency to 1.25 MHz.
The numbers you type appear on-screen to the right of CHAN. If you make a
mistake, correct it any time prior to pressing the MHz terminator by
repeatedly pressing [BKSP] until the incorrect number disappears, and then
enter the correct value.
Pressing a terminator key ([X], [Y], [Z]) determines the units and enters the data.
[X] can represent units of MHz, ms, or mV. Because the frequency immediate
entry mode requires a frequency, the 2715 interprets the currently displayed
value as 1.25 MHz when you press [X]. If a time or voltage unit had been
required, the 2715 would have interpreted your entry as 1.25 ms or 1.25 mV,
respectively, when you pressed [X]
3
. On the other hand, had you wanted the
entry to represent a frequency of 1.25 GHz, you would have pressed [1] [2] [5]
[0] [X]. (Use the correct multiple and [X] to select GHz while the 2715 is in the
CATV mode.)
Now use the direct entry method to set the center frequency to 100 MHz:
13. Press [CHAN/FREQ] [1] [0] [0] [X].
The following procedures demonstrate how to change the frequency when
operating in the nonCATV mode.
Arrow Keys.
You can adjust the frequency using the arrow keys as shown in the
following procedure:
1. Press [CATV/APPL] [8] [0]) to exit CATV mode.
2. Press [1] [0].
3
However, neither is a permissible value at this menu level, and your entry would
have been rounded to the nearest allowable value.
Frequency Entry
(NonCATV Mode)