Extension Antennas; Overview; Antenna Cabling & Cable Loss - SABINE SW71-NDR User Manual

Extension Antennas

Fig. 12b SWASS-EXT-2 Mic-stand mount and
wall-mount extension antennas
Coaxial Cable Attenuation Table - 2.4 GHz
Cable
Type Belden #
RG58 9203
RG58/AU 9311
RG212/U 9861
RG8/U 9913
RG142 83242
Fig. 12c Coaxial Cable Attenuation Table
IMPORTANT
!
Antenna Cabling Impedance
must be 50 Ohm.
Sabine 2.4 GHz Smart Spectrum
12. EXTENSION ANTENNAS

12.1. Overview

Sabine's SWM7000 series receivers are designed for easy interface with
Sabine's SWA-SSEXT-2 Extension Antenna Kit (figure 12b). This triangular,
attractive wood-grained unit is designed to mount easily and unobtrusively on
a wall (allowing either a through-the-wall or out-the-bottom connection), or (by
threading) atop a microphone stand for a more portable or temporary position-
ing. Each package contains 2 Extension Antennas, all necessary mounting
hardware (screws and mic stand thread connectors) and both right-angle and
straight connectors for mating with RG-58 cable (for connections to a receiver
or Antenna Distribution Amplifier).
12.2. Antenna Cabling & Cable Loss
While an extension antenna affords the opportunity to increase the distance
from transmitter to receiver, there is a loss of signal in the interconnecting
cable that limits that distance. The maximum connection length is determined
by the type of cable used, and the degree of signal attenuation acceptable.
Sabine's SWASS-EXT-2 Active Extension Antenna allows for a cost-effective
way of boosting signal levels due to its built-in active switchable (+22 or +44)
signal boost. In the case of low-cost RG-58 cable, adding an SWASS-EXT-2 to
your setup increases the acceptable maximum cable run by more than 4 times,
to 14 meters. With RG-8 cable, the maximum length is extended to 88 meters.
Insulation
Polyethylene
Foam Polyethylene
Polyethylene
Semi-solid Polyethylene
Teflon
Power for the Extension Antenna is delivered from any Sabine SWM7000 se-
ries receiver or SWA6SS Antenna Distribution Amplifier (see Section 11).
!
An additional advantage of using Sabine's SWASS-EXT-2 Extension Antenna
stems from its more focused, directional nature. Sabine receiver's coaxial
dipole antennas (standard equipment that mount directly on the front or rear
panels of the receiver or SWA6SS) are more omni directional in nature. In
contrast, the Sabine's Extension Antenna is sensitive to RF reception in a 135-
degree arc in front of its mounted position. It extends sensitivity to the front and
off-axis side locations as it increases rear RF rejection.
NOTE: The higher boost level (+44 dB) is only recommended for very long
cable runs - at least 50 meters, or you have more than a 12 dB of cable loss.
Using this setting without that much cable loss can cause a signal overload and
poor RF performance.
The multiple functions (relocation of antenna, boost of signal, directional sensi-
tivity) of Sabine's Extension Antenna mean there are many applications in
which its addition to your system can greatly enhance performance. Here's a
short list of such applications and operating instructions:
® Wireless
10 Meter
Center Attenuation
Conductor (dB)
#20 Stranded -16.29
#20 Stranded -11.10
#15.5 solid, -6.11
Silver Plated
#10 Solid -2.50
#18 Solid, -6.54
Silver Plated
36
Maximum
Practical
Distance Using
SWASS-EXT-2
Connector
set for +22 dB
boost (meters)
Type
14 TNC
20 TNC
36 N
88 N
34 TNC