HP ESG Series - FM Source

5-42
Hardkey and Softkey Reference
FM
FM Source
Pressing this softkey reveals a menu of choices for frequency modulation sources.
You can choose internally-generated frequency modulation or select an
externally-applied signal from either the EXT 1 INPUT or EXT 2 INPUT
connectors. The internal modulation is always AC-coupled. For the
externally-applied signals, you can choose between AC- and DC-coupled
modulation. A 1.0 Vpk input is required for calibrated FM deviation settings. The
EXT 1 LO/HI and EXT 2 LO/HI display annunciators will turn on if the peak
input voltage differs from 1.0 Vpk by more than 3%. (The LO/HI annunciators
only function for AC-coupled external inputs.)
The internal and external 1 and 2 sources have multiple uses. You can use them
for amplitude, frequency, and phase modulation. For pulse modulation you must
use the external 2 source. However, any given source can only be routed to one
enabled modulation at a time. If, for example, you were using the external 1
source in a frequency modulation configuration for
FM Path 1, and then you
configured
AM Path 2 to also use the external 1 source, the signal generator would
turn off
FM Path 1 and assign the external 1 source to your AM Path 2
configuration. Notice that for these purposes the external 1 AC-coupled source is
the same as the external 1 DC-coupled source and the external 2 AC-coupled
source is the same as the external 2 DC-coupled source.
Softkey Location: Press
FM/ΦM, FM Source
Status after Normal Preset: Internal
SCPI Commands:
[:SOURce]:FM[1]|2:SOURce?