Tektronix RFM150, Инструкция по эксплуатации

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Making Measurements
2–30 RFM 150 Instruction Manual
Carrier-to-Noise Ratio
In this mode, the instrument measures both the visual carrier level
and the carrier-to-noise ratio. Table 2–7 defines the key actions in
this mode.
Table 2–7: Functions of active keys in C/N measurement mode
Key Action
Menu keys Enters selected menu. (Aborts a partial keypad entry.)
Function keys Tune instrument to preset frequencies. Override partial keypad entry.
Knob Tunes instrument according to entry mode. Overrides partial keypad
entry.
Numeric keypad Keying either channel or frequency, followed by CHAN, MHz, or ENTER,
tunes the instrument – if chan. or freq. is in the active channel table.
CHAN Terminates keypad entry as channel. Switches to channel entry mode.
MHz Terminates keypad entry as frequency. Switches to frequency entry
mode.
ENTER Terminates a keypad entry in the active entry mode (channel or
frequency, as outlined in the top line of the display).
Pressing backspace during a keypad entry erases the character
preceding the cursor. Backspacing 1 click after field is empty aborts
partial entry.
HELP Displays context-sensitive help screen; aborts a partial keypad entry.
ESC Aborts a partial keypad entry without changing the instrument setup.
For an analog channel, the measurement on the top of the display is
the visual carrier level. The bottom measurement is the carrier-to-
noise level. When performing C/N measurements, the RFM 150
automatically compensates for the effects of its own equivalent input
noise. If the noise at the RFM 150 input is so low that the noise
proximity correction can no longer be accurately applied, then a “>”
will precede the C/N readout.
Making Measurements
2–30 RFM 150 Instruction Manual
Carrier-to-Noise Ratio
In this mode, the instrument measures both the visual carrier level
and the carrier-to-noise ratio. Table 2–7 defines the key actions in
this mode.
Table 2–7: Functions of active keys in C/N measurement mode
Key Action
Menu keys Enters selected menu. (Aborts a partial keypad entry.)
Function keys Tune instrument to preset frequencies. Override partial keypad entry.
Knob Tunes instrument according to entry mode. Overrides partial keypad
entry.
Numeric keypad Keying either channel or frequency, followed by CHAN, MHz, or ENTER,
tunes the instrument – if chan. or freq. is in the active channel table.
CHAN Terminates keypad entry as channel. Switches to channel entry mode.
MHz Terminates keypad entry as frequency. Switches to frequency entry
mode.
ENTER Terminates a keypad entry in the active entry mode (channel or
frequency, as outlined in the top line of the display).
Pressing backspace during a keypad entry erases the character
preceding the cursor. Backspacing 1 click after field is empty aborts
partial entry.
HELP Displays context-sensitive help screen; aborts a partial keypad entry.
ESC Aborts a partial keypad entry without changing the instrument setup.
For an analog channel, the measurement on the top of the display is
the visual carrier level. The bottom measurement is the carrier-to-
noise level. When performing C/N measurements, the RFM 150
automatically compensates for the effects of its own equivalent input
noise. If the noise at the RFM 150 input is so low that the noise
proximity correction can no longer be accurately applied, then a “>”
will precede the C/N readout.