Just to let you chaps know - the frequency resolution of the internal wave generator is at least 1Hz when accessed via VISA COM library SICL commands.
I tried to quickly assess the transmission of certain narrow bandwidth bandpass filter and found that the best resolution I can dial via front panel knobs is only +-1kHz around 9.950MHz. Way too rough for my purposes.
I have then whipped up an Agilent Interactive IO utility, punched in
:WGEN:FREQ 9950001 and bingo - the output freq changed to 9,950,001 Hz.
This is confirmed by picking up the signal on my communication receiver and observing beat frequency with the local oscillator. It does vary with at least 1Hz steps.
I can't vouch for absolute accuracy of the frequency but this is good enough for me as I am only interested in relative values.
I am off to program a VB script to sweep the input frequency and read the Vpp filter output voltage from the scope and make nice charts.