TEXIO FGX-2220, Instruction Manual

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159
8-10-6. SOURce[1|2]:FM:DEViation
Set
Query
Description Sets or queries the peak frequency deviation of the
modulating waveform from the carrier waveform. The default
peak deviation is 100Hz.
The frequency deviation of external sources is controlled
using the ±5V MOD INPUT terminal on the rear panel. A
positive signal (>0~+5V) will increase the deviation (up to the
set frequency deviation), whilst a negative voltage will reduce
the deviation.
Note The relationship of peak deviation to modulating frequency
and carrier frequency is shown below.
Peak deviation = modulating frequency
– carrier frequency.
The carrier frequency must be greater than or equal to the
peak deviation frequency. The sum of the deviation and
carrier frequency must not exceed the maximum frequency
for a specific carrier shape. If an out of range deviation is set
for any of the above conditions, the deviation will be
automatically adjusted to the maximum value allowed and an
“out of range” error will be generated.
For square wave carrier waveforms, the deviation may cause
the duty cycle frequency boundary to be exceeded. In these
conditions the duty cycle will be adjusted to the maximum
allowed and a “settings conflict” error will be generated.
Syntax SOURce[1|2]:FM:DEViation {<peak deviation in
Hz>|MINimum|MAXimum}
Parameter <peak deviation in Hz> DC~25MHz
DC~15MHz(square)
DC~1MHz (Ramp)
Example SOUR1:FM:DEV MAX
Sets the frequency deviation to the maximum value allowed.
Query Syntax SOURce[1|2]:FM:DEViation? [MINimum|MAXimum]
Return Parameter <NR3> Returns the frequency deviation in
Hz.
Example SOURce[1|2]:FM:DEViation? MAX
+1.0000E+01
Returns the maximum frequency deviation allowed.