S&C Instruction Sheet 1075-510
9
Table 3. Antenna/Cable Loss Examples with LMR-600 Cable
①
Antenna Gain
Length/Loss
ERP
+8.2 dBi
90 feet (2743 cm)/2.3 dB loss
+36.0 dBm
+10.2 dBi
170
feet (5182 cm)/4.3 dB loss
+36.0 dBm
+12.1 dBi
245
feet (7468 cm)/6.1 dB loss
+36.0 dBm
①
Assuming 1 W output power from the SpeedNet SDR Radio.
Table 4. Antenna Cable Loss Examples with LMR-900 Cable
①
Antenna Gain
Length/Loss
ERP
+8.2 dBi
135 feet (4115 cm)/2.3 dB loss
+35.9 dBm
+10.2 dBi
250
feet (7260 cm)/4.3 dB loss
+36.0 dBm
+12.1 dBi
310
feet (9449 cm)/5.3 dB loss
+35.9 dBm
①
Assuming 1 W output power from the SpeedNet SDR Radio.
IP Basics
SpeedNet SDR Radios use IP version 4, and all references to IP addresses in these installation
instructions refer to IPv4 addresses. An IP address is the unique identifier for a node (host
connection) on an IP network. The IP address is a 32-bit binary number, usually shown as
four decimal values separated by decimal points. Each value represents 8 bits in the range
0 to 255 (known as octets), and this is called “dotted decimal” notation.
For example:
172.26.220.200 can be viewed in binary form:
172.26.220.200
10 1 0 11 0
0.000 11 0 1 0.11 0 11100.11 00 1 000
Every IP address consists of two parts that identify the network and the node. The
address class and subnet mask determine which part belongs to the network address and
which part belongs to the node address.
There are five address classes. You can determine the IP address class by examining
the first four bits of the IP address.
• Class A addresses begin with 0xxx, or 1 to 126 decimal.
• Class B addresses begin with 10xx, or 128 to 191 decimal.
• Class C addresses begin with 110x, or 192 to 223 decimal.
• Class D addresses begin with 1110, or 224 to 239 decimal.
• Class E addresses begin with 1111, or 240 to 254 decimal.
Addresses beginning with 01111111, or 127 decimal, are reserved for loop-back and inter-
nal testing on a local machine. You can test this by pinging 127.0.0.1, which points to your
local machine. Class D addresses are reserved for multicasting, and Class E addresses are
reserved for future use and should not be used for a host address.
This is how the class determines, by default, which part of the IP address belongs to the
network (N) and which part belongs to the node (n).
• Class A–NNNNNNNN.nnnnnnnn.nnnnnnnn.nnnnnnnn
• Class B–NNNNNNNN.NNNNNNNN.nnnnnnnn.nnnnnnnn
• Class C–NNNNNNNN.NNNNNNNN.NNNNNNNN.nnnnnnnn
In the example above, 172.26.220.200 is a Class B address, so by default the network part
of the address (known as the network address) is defined by the first two octets (172.26.
x.x) and the node part is defined by the last 2 octets (x.x.220.200).
To specify the network address in an IP address, the node section is entered as zeros.
In our example, 172.26.0.0 specifies the network address for 172.26.220.200. When the node
section is set to all “1”s, it specifies a broadcast that is sent to all nodes on the network and
is indicated: 172.26.255.255, which is the broadcast address for our example. Note that this
is true for all classes, regardless of the length of the node section.
Installation
