Agilent Technologies PSA Series Service Manual page 170

Hardware Options
Verifying Option 110
Frequency Measured Amplitude
Preamp ON
20 GHz
30 GHz
40 GHz
50 GHz
The accuracy of the measured amplitude will depend on the source
flatness, quality of interconnect cables and whether you performed
Preselector Center, and the frequency response of the PSA. The table
above suggests you test with the preamp on, then with the preamp off
so you can separate the amplitude variation of the preamp from the test
equipment and non- preamp signal path contributions. If the Preamp
On amplitude variation between the frequencies in the table above
seems large, the problem may be that the frequency response correction
factors contained on the A38 Option Driver Assembly are corrupt and
need to be replaced by performing the frequency response adjustment.
See the E4446A/E4447A/E4448A Option 110 and Option 123 block
diagram or the E4440A/E4443A/E4445A Option 110 and Option 123
block diagram for signal level troubleshooting. Be sure to use the
instrument settings listed on the block diagram as a starting point. Run
, then turn
Align All Now
cables and troubleshoot without having
change your measured results.
Signal path troubleshooting on the high frequency instruments
requires connection to devices with 2.4 mm connectors. A short
semi-rigid cable with 2.4 mm male connectors at both ends is
recommended. The required test equipment list on
the Agilent part number of a cable that can be modified (bent) and used
for this purpose.
Figure 8-2 shows the preamplifier pin out/ interconnections and
expected voltage levels. All yellow wires carry the same signal and it
does not matter which VD1 - VD3 pins the wires connect to. The blue
wires all carry the same signal and it does not matter which VG1 - VG3
pins the wires connect to.
170
Measured Amplitude
Preamp OFF
. This will allow you to remove
Auto Align Off
Align All
run unexpectedly and
page 24 contains
Chapter 8