Cisco Aironet 1570 Series, Руководство по установке

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Cisco Aironet 1570 Series Outdoor Access Point Hardware Installation Guide
OL-32138-01
Chapter 4 Installing Other Components
Installing Attenuators, Fuses, and Shunts
Installing Attenuators, Fuses, and Shunts
Installing an Attenuator Plug
You can install an attenuator plug on the RF splitter, in port 8 on the back of the access point (see
Figure 1-4 ).
Plug-in attenuator pads produce flat (even) loss across the forward and reverse frequency spectrum. Pads
are used during station balancing to adjust signal levels as needed. The loss (in dB) produced is equal to
the pad value printed on the top of the pad.
Using a Signal Test Probe
You can use test probes (such as the Communication Associates CA008927) to measure the DS signal
level directly from the attenuator plug-in interface in port 8 on the back of the access point (see
Figure 1-4 ).
You need to remove any installed attenuator pads, which will disconnect the cable modem from the HFC
network. You can then insert the test probe into the plug-in interface, providing an F-connector interface
to directly measure downstream signal levels. Based on the measured signal level, you can decide on an
attenuator value and then plug in the corresponding attenuator pad into the port.
Installing a Fuse or Shunt
You can install a power fuse or a power shunt in port 7 on the back of the access point (see Figure 1-4 ).
Fuses with different fuse ratings are available from Cisco.
Note
By default a 20 A fuse is provided as shunt.
Handling the AP when installing Attenuators, Fuses, and Shunts
To access port 7 or port 8 (see Figure 1-4 ):
•
For strand mounted APs, you can access ports 7 and 8, without having to dislodge the AP from its
mount.
• For pole and wall mounted APs, you can following one of the following procedures, depending on
your mounting kit,
For pole mounted and wall mounted APs, mounted using PMK1 or PMK2, to access port 7 or port 8:
Step 1
Slide the AP up, off the wall mount bracket’s key hole slots.
Step 2 Remove the four M8 x 12mm hex head bolts from the back of the AP, and then fix them on the face of
the AP in the screw holes intended for future external module support (see
Face of the AP, page 1-4 ). Do
not fully tighten the bolts.