I'm in the market for a used spectrum analyzer like the 7L12
or the HP 141-T. One important use will be to make two-tone
IMD measurements on HF SSB transmitters. I am concerned that
with tone separations on the order of one kHz, the 7L12 may
not have sufficient bandwidth in the 300 Hz mode to resolve
adjacent IMD products expected to differ in amplitude by 40
dB or more.

Has anyone on the group used a 7L12 for this purpose and is
the 300 Hz RBW sufficiently narrow?

There seems little doubt that the 141, with 10 Hz or 100 Hz
RBW, will handle this.

Many thanks in advance.

Chuck
NT3G