How To Use The Chart; Changing Attenuation; Table 1-4. Selecting Hp 85326A Reference And Test Attenuation - HP 85325A Operating And Service Manual

Table 1-4 Selecting HP 85326A Reference and Test Attenuation
Length of LO Cable from
HP 85309A
(L Cable)
V
9 meters
8 meters
7 meters
6 meters
5 meters
4 meters
1.5 to 3 meters
1. Assumes use of HP 85381A cable type.
2. A standard HP 85325A system uses 8, 6, or 4 meter cables.

How to Use the Chart

Determine the length of the LO cable that goes from the HP 85309A REF
LO OUT connector to the reference module's LO IN connector.
Look the length up in Table 1-4 to find the appropriate amount of attenuation
for the test and reference modules.
HP cables have label sleeves marked C04, C06, or C08. The number
represents the length of the cable in meters. Standard systems use LO cables
that are 4, 6, or 8 meters in length. Other lengths are not standard but might
apply to special systems.

Changing Attenuation

Procedure
1. Use the supplied #10 TORX driver to remove the screws securing the
module covers.
2. Observe the attenuator that is connected to the reformable cable. Hold
the body of this attenuator in place with one of the supplied 5/16 inch
wrenches.
3. Use the other 5/16 inch wrench to disconnect the reformable cable.
4. Remove other attenuators, as required, using this method.
5. Place unused attenuators in the holders (see Figure 1-2 and Figure 1-3
on page 1-10.)
6. Replace the reformable cable.
Reference Module
1 2
to Reference Module Attenuation Required
0 dB
1 dB
1 dB
2 dB
2 dB
3 dB
3 dB
Mixer LO Power Level Adjustment
Test Module Attenuation
Required
0 dB
0 dB
1 dB
1 dB
2 dB
2 dB
3 dB
HP 85325A Operating and Service Manual 1-9
Installation