3-6
HP 85325A Operating and Service Manual
General Information
Maximum RF Cable Lengths
Maximum RF Cable Lengths
In millimeter-wave systems, there is a length limit on the HP 85381A LO
cable that goes from the LO source to the LO INPUT of the HP 85309A (L
S
)
and the L
R
cable (the cable that goes between the REF LO OUT of the
HP 85309A and the LO IN on the reference module).
L
S
= source module cable
L
R
= reference module cable
L
T
= test module cable
Refer to Figure 3-1 and Table 3-6 to determine the maximum L
S
length.
Figure 3-1
L
S
, L
R
, and L
T
Cables
Table 3-6
Maximum Cable Lengths (meters)
Cable Type
LO Frequency (max)
GHz
LO Source to
HP 85309A (L
S
)
HP 85309A to
HP 85325A/B (L
R
, L
T
)
HP 85381A
6
17
6
MaCom FA29RX
6
18
11
