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SB9SBJ-174LN-5 is a 50 ohm RG174 low noise 5 foot cable with
a SMB 90 degree (right angle) plug (female contact) connector
on one end and
a SMB jack (male contact) connector
on the other
end.
RG174 alternate designations: RG-174 RG174A/U RG-174A/U
"The MINI Cooper Cable"
This cable and its variants have become popular with BMW MINI Cooper
satellite radio installers -- it's about the right length for an
antenna extension cable running from the OEM connector under the seat
to the tuner. We understand this works with the Sirius Inv and XM
Roady and Sportscaster tuners, and should work with any tuner that has
an SMB jack (male contact) connector. Other lengths may be needed for
other vehicles. See
North American Motoring for more discussion. (Or hit the
"Reviews" button below and start a thread here.)
The MINI's built-in antenna generally provides better reception than
the magnet-mount antenna that comes with most satellite radios. We
suspect this is at least in part because the built-in provides a much
better ground
plane. Other considerations are aesthetics, as well as
security: Magnet mount antennas attract unwelcome attention to the
contents of a parked vehicle (something we once discovered the hard
way).
Sirius and XM both operate in the 2.3 GHz band. Sirius uses
2320.0-2332.5 MHz, while XM is 2332.5-2345 MHz. To put that in
perspective, a hypothetical 1/8 wavelength antenna for Sirius would be
about 16.11 mm long, and XM would be about 16.02 mm. While using an
XM receiver with a Sirius antenna is not an exact wavelength match,
using an XM receiver with a MINI's built-in Sirius antenna may
actually work better than using a magnet-mount XM antenna with a poor
ground plane -- much depends on the exact antenna design, as well as
other variables which we wouldn't want to guess at. See this
article for one in-depth treatment. The upshot is that your
mileage will vary.
Most folks are buying the low-noise version of this cable with the
straight SMB jack (SB9SBJ-174LN-5), while a
few opt for the version with a right-angle SMB jack instead (SB9SBJ9-174LN-5). We
don't own a Mini ourselves, so can't comment on the fit of either of
these. The SMB jack is the end of the cable which plugs in under the
seat -- take a look at the angle of what you're plugging into, and you
should be able to see what will work best for you.
When the car's not moving, you should theoretically be able to get
best RF reception with ordinary RG174 (SB9SBJ-174-5 or SB9SBJ9-174-5), but the
low-noise versions of this cable seem to be preferred for preventing
possible signal disruption due to the mechanical vibrations of a
vehicle in motion. Again, we don't own a MINI, so haven't done
empirical testing. The people using the low-noise cables are saying
things like "fantastic" to describe their results, while as of this
writing we haven't seen anyone try ordinary RG174 for this
application.
This cable has a conductive PVC layer added around the polyethylene
dielectric; this layer helps to increase shielding, dissipate static
charge, and reduce mechanically-generated electrical noise as the
cable is flexed. This extra protection is useful for long cable runs,
low-voltage signals, high-vibration environments, in applications
including aerospace, automotive, NDT, DX ham radio, strain gauges and
accelerometers, and extremely high fidelity professional audio and
video production.
This cable assembly has a
characteristic
impedance of 50 ohms.
50 ohm cable, connectors, and adapters are commonly used in wifi
(802.11 wireless LAN) antennas, ham tranceivers, and other radio
frequency (RF) analog and digital signaling, microwave, radar,
hi-fidelity professional audio, non-destructive testing (NDT), oil and
petroleum production, ultrasonic transducers, accelerometers, strain
gauges, and some professional video applications.
If you need a quantity discount quote or have other special requests,
please contact us. We're always happy
to work with distributors.
Cable Features:
- Our mass-produced cables are manufactured in our own
facilities; our custom-made cables are handcrafted by
experienced specialists in the heart of Silicon Valley.
- We hi-pot (high voltage) test our cable assemblies to 1500V
(low noise to 500V, SMA and SMB to 1000V). See About Hi-Pot Testing
below for why this might matter to you, for both high and low-voltage
applications.
If you plan to use
this cable in a high-voltage application, please read the
safety-related caution in that section.
- RoHS compliance available upon request.
About Hi-Pot Testing
High-power applications can cause cables to fail if the cables aren't
built right. High transmit power in radio, or composite materials,
air-coupled scanning, and other high power domains in nondestructive
testing, can cause radio transmitters or NDT pulser-receiver equipment
to drive antennas or ultrasonic transducers with energies that can
exceed 1000 volts. But the connectors made for small-diameter cable
are typically designed and rated by manufacturers for as little as 30
volts. Too often the result is arcing, dielectric breakdown, poor
signal performance, and in most cases an eventual total cable or
connector failure, as carbon traces build up and cause a short between
conductors. But entire industry segments use these low-voltage
components anyway, often for historical reasons dating back to times
when power demands were not as high.
The same defects which cause high-voltage breakdown can cause
problems in low-voltage applications as well. Contamination or
air-gap issues affect the cable's impedance at the point where the
defect exists, causing internal reflections, leading to signal loss,
noise, and, in extreme cases, damage to transmitter circuitry.
In order to prevent this and other mishaps from happening to you, we
test to destruction when selecting suppliers and connector designs.
During assembly, we use techniques and materials that we've evolved
over time to greatly improve the voltage-carrying capacity of these
parts. Before shipping, we test each and every cable assembly we
build -- we don't simply pull a few out for an audit check. Even with
this added cost in our manufacturing process, we still ship some of
the least-expensive cables in the industry, and we're content knowing
that these cables will perform reliably in the field.
Caution: We make no claims as to the safety of this product for
high-voltage use. These voltages can kill. Do not handle or
approach any cable or conductor carrying high voltage; this
includes insulated cables, nearby metal parts, water, and other
conductive materials. Engineering and design for safety in your
application are your responsibility. The hi-pot test results
mentioned here are not an indicator of human, animal, or
equipment safety around these cables when carrying high voltage. We
do not test for high-voltage breakdown of the external
insulating jacket, and field conditions can easily contaminate or
damage the outside jacket and its insulating capacity. In a
high-voltage application, you should ensure that you are using the
braid for earth ground -- though that alone is not enough to ensure
safety. When we work with these voltages, we take extensive safety
precautions, and you need to as well.
All prices are subject to change without notice.
Actual product color, plating, and other details may differ from photo images depending on upstream component availability.
All images and text on this web site are copyright CD International
Technology; all rights reserved.
All trademarks and registered trademarks are the property of their
respective owners. LEMO is a registered trademark of LEMO USA.
Microdot is a trademark of Tyco Electronics.
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