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WHAT IS MURS?
In the fall of 2000 the FCC created a new license free VHF Citizen Band Radio Service. This new service is commonly
referred to as the Multi-Use Radio Service (MURS). Initially, MURS radios can have 5 channels in the 151.820 to 154.600
MHz frequency range with 2 watts of transmitter power. Unlike the Family Radio Service (FRS) with its limited 1/2 watt
output and fixed antennas, MURS applications may use external antennas and can be supplied in mobile, handheld and base
configurations. This new service has the potential to become very popular, especially within the mobile sector, because
of its ability to use external antennas and the fact that the VHF band is typically much clearer than the current HF
frequencies utilized by common CB radios. For those unaware of frequency allocations, the MURS frequencies skirt those
that are currently used by the professional (licensed) business band radio services.
AUTHORIZED MURS FREQUENCIES
151.820 MHz * 151.880 MHz * 151.940 MHz * 154.570 MHz * 154.600 MHz
YOUR DEMAND WILL PUSH THE MARKET
Since MURS is a new service, there will be some initial product voids as knowledge of this service expands and demand
prompts radio manufacturers to fill those voids. Today, your best bet to obtain a new MURS radio will come in the form
of a handheld model. With the MURS frequencies being so close to the business band spectrum, manufacturers will be able
to easily modify existing radio lines to fulfill the MURS requirements. There are handheld models available today.
ANTENNA RESTRICTION DROPPED
The original MURS ruled limited limited effective radiated power (ERP) to 2-watts. In effect, if you had a 2-watt
transmitter you were only allowed by the rules to use a zero gain antenna. If a 6db gain antenna was going to be used, the
transmitter power would need to be decreased from 2-watts to 1/2-watt in order to maintain the 2-watt ERP restriction.
Somebody finally realized that it would be impossible, at best, to regulate that rule and the rules were changed to allow
for a 2-watt output at the transmitter and NO antenna restriction. So now ... you can use a good gain antenna without
breaking any rules.
FIRESTIK ANTENNAS IMPROVE ERP
Both of the short Firestik MURS Antennas (MURS16-B and MURS-16S-B) produce 3db of gain and increase the effective radiated
power (ERP) of the transmitter by a factor of 2.1 (from 2-watts of transmitter power to 4.1-watts ERP). Our 5/8 wave MURS45
and the MURS-Base antennas produce 6db of gain and increase the effective radiated power (ERP) of the transmitter by a
factor of 4 (from 2-watts of transmitter power to 8-watts ERP
TODAY, TOMORROW, THE FUTURE
At the present time there has been little promotion with regards to MURS, but once the benefits become known to the general
public we expect its popularity to spread rapidly throughout the public communications community. We want to take a lead in
making this new service more available to the public. To that end, we have designed a series of high performance antennas
to work with the MURS frequencies. By doing this we will increase the public awareness of this new service and as demand
increases, availability of products will increase as well. You will be a part of the MURS growth if you have an interest
in communication performance that offers you benefits that up until now were limited to those who wanted to jump through
the hoops to get an FCC license. MURS will start with your interest and grow with your demands.
FIRESTIK MURS ANTENNAS
Model MURS45: This antenna is a full-fledged, 5/8's wave top
performer. With the 6dBi gain offered by this antenna, your 2-watt MURS radio can produce an equivalent of 7.8 watts
ERP at the antenna with SWR at 1.5:1 (7.1 watts ERP at 2.0:1 SWR). The MURS45 utilizes common 3/8"-24 threads on the
base, which allows it to utilize the numerous mounts, and accessories that are available for standard CB radio applications.
The MURS45 is 45 inches (114cm) tall and is wound on 3/8" fiberglass. Available in black or white.
Model MURS16: This is a little antenna with a big attitude. The
MURS16 is a 3dBi tunable tip 1/4 wave antenna that stands 16-inches (41cm) tall. These antennas are hand-wound on 5/16"
fiberglass with 3/8"-24 threads to allow the user to have full access to numerous mounts and accessories. On our design
test station we tuned the antenna to 153.2 MHz (center of MURS band) and performed a sub 2.0:1 SWR bandwidth scan and
recorded an amazing frequency span that went from 143.43 MHz to 168.11 MHz.. And that was without ever moving the tuning
screw from its desired resonant position.
Model MURS16S: The MURS16S is similar to the MURS16 with the
exception of a medium duty stainless steel spring that is calculated in to the over all design of the antenna. This
would be of particular interest to owners of high profile vehicles or those who find that their antenna is consistently
exposed to brush or low hanging tree limbs.
Model MURS-BASE: The MURS Base antenna uses our 6dBi, 5/8-wave
antenna for its radiating element. A central hub piece supports the supplied 21" radials (4 pieces). A mast-mounting
bracket with hardware is included, as is the antenna stud with connections for standard PL-259 terminated coax cable.
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