20
SD Series Technical Manual
MDS 05-4846A01, Rev. F
Table 3, Table 4, and Table 5 show the approximate losses that will
occur when using various lengths and types of coaxial cable in the 200,
400 and 960 MHz bands, respectively. Regardless of the type used, the
cable should be kept as short as possible to minimize signal loss.
4.3 DC Power Connection
The transceiver may be operated from any well-filtered 10.0 to 30 Vdc
power source. The supply must be capable of providing at least 2.5
Amperes continuously.
NOTE:
Early SD4 models supported 10.5 to 16 Vdc power, not 10 to
30 Vdc.
Always check the labeling above the power connector
to confirm the operating range for your unit.
Table 3. Signal Loss in Coaxial Cables (at 200 MHz)
Cable Type
10 Feet
(3 Meters)
50 Feet
(15 Meters)
100 Feet
(30.5 Meters)
200 Feet
(61 Meters)
RG-8A/U
0.26dB
1.27 dB
2.5 dB
5.07 dB
1/2 inch HELIAX
0.06 dB
0.38 dB
0.76 dB
1.6 dB
7/8 inch HELIAX
0.04 dB
0.21 dB
0.42 dB
0.83 dB
1-1/4 inch HELIAX
0.03 dB
0.16 dB
0.31 dB
0.62 dB
1-5/8 inch HELIAX
0.025 dB
0.13 dB
0.26 dB
0.52 dB
Table 4. Signal Loss in Coaxial Cables (at 400 MHz)
Cable Type
10 Feet
(3 Meters)
50 Feet
(15 Meters)
100 Feet
(30.5 Meters)
200 Feet
(61 Meters)
RG-8A/U
0.51dB
2.53 dB
5.07 dB
10.14 dB
1/2 inch HELIAX
0.12 dB
0.76 dB
1.51 dB
3.02 dB
7/8 inch HELIAX
0.08 dB
0.42 dB
0.83 dB
1.66 dB
1-1/4 inch HELIAX
0.06 dB
0.31 dB
0.62 dB
1.24 dB
1-5/8 inch HELIAX
0.05 dB
0.26 dB
0.52 dB
1.04 dB
Table 5. Length vs. Loss in Coaxial Cables (at 960 MHz)
Cable Type
10 Feet
(3.05 Meters)
50 Feet
(15.24 Meters)
100 Feet
(30.48 Meters)
200 Feet
(61 Meters)
RG-8A/U
0.85 dB
4.27 dB
8.54 dB
17.08 dB
1/2 inch HELIAX
0.23 dB
1.15 dB
2.29 dB
4.58 dB
7/8 inch HELIAX
0.13 dB
0.64 dB
1.28 dB
2.56 dB
1-1/4 inch HELIAX
0.10 dB
0.48 dB
0.95 dB
1.90 dB
1-5/8 inch HELIAX
0.08 dB
0.40 dB
0.80 dB
1.60 dB