Tektronix 2715, Руководство пользователя

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Getting Started
2–18
2715 User Manual
This method of changing frequency is very useful for scanning relatively small
bands. To change by larger amounts, use the immediate entry mode to set the
center or start frequency to a predetermined value.
13. Press [CHAN/FREQ] to place the center or start frequency in the immediate
entry mode.
Notice that the abbreviation FREQ appears at left center of the screen.
The FREQ indicator tells you that you can enter the center frequency directly
from the keypad by keying in a permissible value followed by an appropriate
terminator key.
14. Press [1] [0] [1] to set the center frequency to 101 MHz.
The numbers you press appear on screen to the right of FREQ. If you make a
mistake, you can correct it by repeatedly pressing the backspace key until the
incorrect number disappears and then entering the correct value.
15. Press [X] after the correct number has been entered.
This key can represent units of MHz, ms, or mV. Had you wanted to set the
frequency to 101 kHz, you would have pressed [Y].
This method of changing center or start frequency is most useful when large
changes are required or if you know ahead of time exactly what frequency is
required.
The span is now set to 6 MHz and the fundamental of the calibrator signal is not
quite centered on screen. Center the calibrator signal with the FREQ/MKRS
knob.
16. Turn the FREQ/MKRS knob several clicks counterclockwise to reduce the
center or start frequency.
Each click reduces the frequency by the currently selected tuning increment
(0.02 times the span/div, or 0.12 MHz in this case). The control functions as
the “fine” frequency adjustment. Rotating the knob clockwise increases the
frequency at the same rate.
17. Continue turning the knob in either direction until the signal is centered.
Your screen should now resemble Figure 2–6.