HP 8753E User Manual page 147

4. Measure the output power in the R channel by pressing:
Observe the 13 to 16 dR offset in measured power. The actual input power level to the R
channel input must be 0 dBm or less, -10 dRm typical, to avoid receiver saturation effects
The minimum signal level must be greater than -35 dBm to provide sufficient signal for
operation of the phaselock loop.
5. You cannot trust R channel power settings without knowing about the offset involved.
Perform a receiver calibration to remove any power offsets by pressing:
Once completed, the R channel should display 0 dRm. Changing power ranges will require a
recalibration of the R channel.
Figure 3-3. B Channel External Connection
Mating Mixer Measurements