R&S SMJ100A, Руководство по эксплуатации

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Instrument Function
R&S
®
SMJ100A
241 Operating Manual 1403.7458.32 ─ 14
Remote command:
[:SOURce<hw>]:MODulation[:ALL][:STATe]
on page 758
Modulation Sources
The following modulations use internal and external modulation sources:
●
Amplitude modulation
●
Pulse modulation
●
Frequency modulation
●
Phase modulation
Only external modulation sources can be used for a BB-AM.
Internal Modulation Sources
The LF generator is available as internal modulation source. The generator supplies
sinusoidal signals in the frequency range 0.1 Hz to 1 MHz. With pulse modulation, the
sinusoidal signal from the LF generator is formed internally into a rectangular signal
used to actuate the pulse modulator.
The noise generator supplies white noise with selectable bandwidth and level distribu-
tion.
See also Chapter 5.5.12.1, "Overview of LF Generator" , on page 253.
External Modulation Sources
The EXT MOD input at the rear of the instrument is provided as the external modula-
tion source for amplitude, pulse, frequency and phase modulation. The external signal
for broadband amplitude modulation is fed in via the I-input.
The external modulation signal for AM, FM and PM at the input must have a voltage of
U
S
= 1 V (U
EFF
= 0.707 V) in order to achieve the displayed modulation depth and
range. The input voltage should not exceed 1 V, otherwise modulation distortions might
occur.
The input shows some hysteresis with threshold levels of 1.1 V/1.7 V. The voltage
must not exceed 10 V
Simultaneous Operation of Several Modulations or Other Operating Modes
The table shows the modulations and operating modes which can be activated simulta-
neously (+) or which deactivate each other (-).
AM FM PhiM Pulse BB-AM I/Q DM ARB
Amplitude modulation (AM) / + + + - - - -
Frequency modulation (FM) + / - + + + + +
Phase modulation (PhiM) + - / + + + + +
Pulse modulation + + + / + + + +
Broadband AM (BB-AM) - + + + / - - -
RF Signal and Analog Modulations - RF Block