Site Preparation
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TM
4812ET RF and Power Cabinet Hardware Installation Manual
Apr 2001
44
It may not be necessary or desirable to run the transmission
lines in any conduit at all. In this case the transmission
lines should be protected from falling objects (i.e., ice,
etc.) or from being stepped on.
NOTE
Table 2-6: Heliax Cable Loss and Minimum Bend Radii
Heliax
Motorola Part
dB loss per meter
dB loss per foot
Min. bend radius
Heliax
Cable
Motorola Part
No.
@ 1 GHz
@ 2 GHz
@ 1 GHz
@ 2 GHz
Metric
U.S.
RG 142
CGDSRG142BU
.49
.66
.15
.20
10 mm
.4”
3/8” LDF
N/A
.115
.167
.035
.051
95 mm
3–3/4”
1/2”LDF
SGDN4232A
.0768
.1132
.0234
.0345
125 mm
5”
1/2” FSJ4
N/A
.119
.177
.0363
.0541
13.75 mm
1.25”
7/8”LDF
SGDN4234A
.0430
.0646
.0131
.0197
250 mm
10”
1–1/4”LDF
SGDN4235A
.0317
.0476
.00967
.0145
380 mm
15”
1–5/8”LDF
SGDN4233A
.0269
.0410
.00819
.0125
510 mm
20”
NOTE
As an additional rule of thumb, allow 0.1 dB additional loss for each connection point.
Table 2-7: Number of wires in Conduit
Conduit
Foam Heliax Trade Size (Cable Type LDF)
Conduit
Trade Size
9.5 mm (3/8”)
12.7 mm (1/2”)
21.4 mm (7/8”)
31.8 mm (1–1/4”)
41.3 mm (1–5/8”)
2”
5
2
1
–
–
2–1/2”
7
3
1
–
–
3”
11
5
3
–
–
4”
19
9
5
1
1
6”
20
20
12
3
2
* IMPORTANT
The values listed above were calculated based on the percent of conduit cross–section filled and recommended
limits set forth by Andrew Corporation. These limits are based on common conditions or proper cabling and
alignment of conductors where the length of pull and the number of bends are within reasonable limits. It
should be recognized that for certain conditions a larger size conduit or a lessor fill should be considered.
Power Cabinet AC Power Connection
208–240 VAC – Flexible Liquid Tight Conduit is recommended.
2