Atek HP 8753D, User Manual, Page: 136 / 677

High Dynamic Range Swept RF/IF Conversion Loss
The HP 8753D's frequency oset mode enables the testing of high dynamic range frequency
converters (mixers), by tuning the analyzer's high dynamic range receiver above or below its
source , by a xed oset. This capability allows the complete measurement of both pass and
reject band mixer characteristics .
The analyzer has a 35 dB dynamic range limitation on measurements made directly with its R
(phaselock) channel. F or this reason, the measurement of high dynamic range mixing devices
(such as mixers with built in amplication and ltering) with greater than 35 dB dynamic range
must be made on either the analyzer's A or B channel, with a reference mixer providing input
to the analyzer's R-channel for phaselock.
This example describes the swept IF conversion loss measurement of a mixer and lter . The
output ltering demonstrates the analyzer's ability to make high dynamic range measurements .
T o avoid the complexity of performing a separate power meter calibration over the RF
frequency range while the mixer under test and reference mixer are operating, a broad band
power meter calibration is used. The broad band calibration covers the entire range of IF and
RF frequencies .
1. Set the following analyzer parameters:
4
PRESET
5
4 ST ART 5 4 100 5 4 M/ 5
4 STOP 5 4 2.5 5 4 G/n 5
4 MENU 5
NNNNNNNNNNNNNNNNN
POWER
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
PWR RANGE MAN 4 0 5 4 x1 5
2. Calibrate and zero the power meter .
3. Connect the measurement equipment as shown in Figure 3-10.
Caution
T o prevent connector damage , use an adapter (HP part number 1250-1462) as a
connector saver for R CHANNEL IN.
3-12 Making Mixer Measurements