= Pulse generator
A <pulse generator> produces controlled electrical pulses for exciting, triggering or testing an <electrical circuit>. The useful specification includes high and low levels, <pulse width>, repetition period, edge behavior and the timing relationship to a trigger. A repeating pulse train and a single triggered pulse impose different test conditions even when their individual pulse shapes agree.
For an original ideal train with low level zero, high level $V_p$, <pulse width> $\tau$ and period $T$, define <duty cycle> $D=\tau/T$ and repetition <frequency> $f=1/T$. Direct averaging gives
$$
\langle v\rangle=DV_p,\qquad V_{\rm rms}=V_p\sqrt D.
$$
For a resistive load $R$, the <energy> per pulse and mean <active power> are
$$
E_p=\frac{V_p^2\tau}{R},\qquad P_{\rm avg}=fE_p=\frac{DV_p^2}{R}.
$$
Mean potential difference and RMS potential difference are different summaries; squaring the mean would underestimate heating for a nonconstant waveform.
Take $V_p=2\,\mathrm V$ actually delivered into $R=50\,\Omega$, $\tau=10\,\mathrm{\mu s}$ and $T=100\,\mathrm{\mu s}$. Then $D=0.1$, $f=10\,\mathrm{kHz}$, mean potential difference is $0.2\,\mathrm V$, and RMS potential difference is about $0.6325\,\mathrm V$. The pulse deposits $0.8\,\mathrm{\mu J}$ and average load <power> is $8\,\mathrm{mW}$. These are stipulated rectangular-pulse values, not instrument limits.
Real <pulse width> needs a threshold definition. Keysight's primary control documentation measures it between the rising and falling 50% crossings and provides duty-cycle entry as an alternative.<Pulse Width in Keysight BenchVue Function Generator documentation>[Pulse Width, definition and duty-cycle setting]{ref} <Rise time>, edge asymmetry and trigger timing must be measured or specified separately; a nominal width alone does not describe the full waveform.
Termination also changes what reaches the load. The existing Keysight documentation explains a fixed series output impedance and the difference between a selected load setting and the actual connected load. Its example gives twice the displayed amplitude at an open circuit when the display assumes a matched 50-ohm load.<Output Load Termination in the Keysight BenchVue Function Generator documentation>[Output Load Termination, first paragraph and open-circuit example]{ref} Use the delivered pulse levels in the energy calculation.
A proposed test connects the intended termination, records the pulse at the load with an <oscilloscope>, and checks levels, crossing times and repetition intervals. Varying pulse width at fixed amplitude and repetition rate should change resistive average <power> in proportion to $\tau$ under the ideal model. Loading and finite edge durations explain departures that should not automatically be assigned to the programmed timing.
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