Why Use PRS?
PRS Radio's are small, lightweight and powerful. PRS radio's
are perfect to keep a group together, whether you're hiking, camping,
at the
marina,
or at the mall perfect for car caravanning, at amusement parks
and to keep track of the kids around the neighborhood.
What is PRS?
The Ministry of Commerce (MOC) authorized Personal
Radio Service in 1996 as a short distance, unlicensed, two-way
voice radio service for general purpose use. Personal Radio Service
is
meant to be used for direct, personal voice communications among
two or more people.
PRS radios are personal two-way (send/receive) radios which conform
to the MOC PRS specifications. In brief, they're an inexpensive and
easy way to communicate with family and friends.
FM vs. AM. What is the Difference?
UHF CB uses the FM transmission mode. UHF gives clear, crisp local
communication without the long-distance interference sometimes heard
on 26 MHz. UHF is also less susceptible to power line noise than
26 MHz. Its main disadvantage is that it performs poorly in hilly
and forested areas due to its 'line of sight' characteristics. Typical
direct (simplex) car-to-car ranges of UHF vary between about 5 ~
10 kilometres in urban areas to 20 kilometres or more in open countryside.
However if located on a hilltop, distances of 50 kilometres are common,
even with low-powered handheld equipment.
UHF really comes into its own when repeater stations are used.
Repeaters are installed on hilltops and retransmit signals received
on one channel onto another channel. They are set up by community
groups or commercial organisations but can freely be used by everyone.
Distances of 50 to 100 kilometres are commonly achieved via repeaters,
even if mobile or handheld transceivers are used. Many urban and
rural areas are served by at least one repeater. To listen for the
repeaters in your area, search for signals between channels 1 and
8. Those channels are busy most of the time are likely to be repeaters.
They can be used within a neighborhood or while at a shopping mall,
ball game, amusement park, etc. PRS radios can be used by groups
engaged in activities that take people out of sight or earshot of
each other while remaining in the same general area, such as while
hiking, hunting, camping, bicycling, or caravanning. PRS radios are
small, rugged, and easy to use so they can be used by children as
well as adults.
AM Frequency Chart
| Ch |
Frequency |
|
Ch |
Frequency |
|
Ch |
Frequency |
|
Ch |
Frequency |
| 1 |
26.330 |
|
11 |
26.450 |
|
21 |
26.580 |
|
31 |
26.680 |
| 2 |
26.340 |
|
12 |
26.470 |
|
22 |
26.590 |
|
32 |
26.690 |
| 3 |
26.355 |
|
13 |
26.480 |
|
23 |
26.620 |
|
33 |
26.700 |
| 4 |
26.370 |
|
14 |
26.490 |
|
24 |
26.600 |
|
34 |
26.710 |
| 5 |
26.380 |
|
15 |
26.500 |
|
25 |
26.610 |
|
35 |
26.720 |
| 6 |
26.390 |
|
16 |
26.520 |
|
26 |
26.630 |
|
36 |
26.730 |
| 7 |
26.400 |
|
17 |
26.530 |
|
27 |
26.640 |
|
37 |
26.740 |
| 8 |
26.420 |
|
18 |
26.540 |
|
28 |
26.650 |
|
38 |
26.750 |
| 9 |
26.430 |
|
19 |
26.550 |
|
29 |
26.660 |
|
39 |
26.760 |
| 10 |
26.440 |
|
20 |
26.570 |
|
30 |
26.670 |
|
40 |
26.770 |
Channel 15 is the AM Emergency/Call Channel.
Channel 35
is the SSB (LSB - Lower Side Band), Call Channel.
Channels 1-17 & 25-40 should be used for AM & SSB Transmission.
Channels 8-24 are to be used for AM Transmission ONLY
Channel 11 is widely used by Trucking.
UHF FM Frequency Chart
| Ch |
Frequency |
|
Ch |
Frequency |
|
Ch |
Frequency |
|
Ch |
Frequency |
| 1 |
476.425 |
|
11 |
476.675 |
|
21 |
476.925 |
|
31 |
477.175 |
| 2 |
476.450 |
|
12 |
476.700 |
|
22 |
476.950 |
|
32 |
477.200 |
| 3 |
476.475 |
|
13 |
476.725 |
|
23 |
476.975 |
|
33 |
477.225 |
| 4 |
476.500 |
|
14 |
476.750 |
|
24 |
477.000 |
|
34 |
477.250 |
| 5 |
476.525 |
|
15 |
476.775 |
|
25 |
477.025 |
|
35 |
477.275 |
| 6 |
476.550 |
|
16 |
476.800 |
|
26 |
477.050 |
|
36 |
477.300 |
| 7 |
476.575 |
|
17 |
476.825 |
|
27 |
477.075 |
|
37 |
477.325 |
| 8 |
476.600 |
|
18 |
476.850 |
|
28 |
477.10 |
|
38 |
477.350 |
| 9 |
476.625 |
|
19 |
476.875 |
|
29 |
477.125 |
|
39 |
477.375 |
| 10 |
476.650 |
|
20 |
476.900 |
|
30 |
477.150 |
|
40 |
477.400 |
Repeaters transmit between channels 1-8 and receive between channels
31 and 38. Avoid these channels for non-repeater (simplex) communications.
If you are near the station you are talking to, you should move
from the repeater to a simplex channel to leave the repeater
free for others who cannot communicate direct.
Equipment Both handheld and mobile equipment is available for UHF. All currently
available radios cover all 40 channels and can be used with repeaters.
Like 26 MHz there are no base station transceivers. Instead use a
mobile transceiver connected to a 13.8 volt power supply and a base
station antenna mounted outside.
All mobile transceivers put out the full five watt legal limit.
Thus there is very little difference in communications range between
more expensive and cheaper units. However the better units have extra
features that can be useful. Examples include (1) ability to search
all channels for activity without manually turning the channel selector
(scanning), (2) a signal strength meter, (3) a frequency readout
as well as channel number and (4) CTCSS tone squelch to reduce reception
of unwanted signals.
Handheld transceivers vary more widely than mobile transceivers
in both features and price tag. The cheapest sets, do not come with
rechargeable batteries and cannot be connected to external antennas
or power. Nevertheless if only short range is required, they work
well, are very compact and have good battery life.
Middle and upper range handheld UHF transceivers include most or
all of the following: (1) 5 watt power output, (2) rechargeable battery
pack and charger, (3) CTCSS subtone, (4) voice operated transmit
(VOX), and (5) ability to connect external antenna and power. This
last feature allows handheld transceivers to be operated from a car.
However unless extensive use outside the car is planned, a car-mounted
transceiver is easier to use and represents better value for money.
Controls found on most UHF CB transceivers
Channel select: allows you to switch between channels 1-40. This may either
be a rotary knob or up/down buttons.
On/off/volume: self-explanatory
Squelch or mute: Adjust at point where noise stops. This allows
silent monitoring of channel. If someone talks the squelch is 'broken'
and you will hear their voice. Disable the mute (by adjusting for
hiss) if signals are weak. On handheld transceivers this function
may be performed by a 'monitor' button, which unmutes the set when
it is pressed.
Simplex/Duplex switch: If operating direct (no repeater) leave
this switch in simplex position. To operate through a repeater select
the appropriate repeater channel (between 1-8) and switch to Duplex.
Scan: Allows the radio to search for activity across all 40 channels.
The scanning will stop as soon as a busy channel is found.
Other controls you may find include CTCSS, memory, power output
select and VOX. Mastery of these is not required for basic operation.
The transceiver's instruction manual will explain how to use these
functions.
UHF CB is the best choice for most given current activity levels
and trends.
For whom is CB unsuitable?
The low price of PRS Family Radio (especially compared to other two way radio
systems) is attractive, but like everything that's cheap, there are limitations.
The following are things that PRS radio will not do:
- Long-distance outback communications. If you stick to the main
roads, a UHF CB is fine. But in very remote areas where long-distance
coverage is required, it is next to useless. Instead hire an
HF transceiver from the Mountain Radio Service.
- Reliable coverage over an entire metropolitan area. Five watts
is too low to permit simplex city-wide communication. Metropolitan
coverage is possible with UHF repeaters, but these can be busy,
interfered with or turned off without warning. Rather than use
PRS, serious
business users should discuss their needs with a specialist two-way
radio company, which will be able to supply equipment and provide
access to wide-coverage VHF or UHF repeaters.
- Privacy. CB is a public medium with possible people listening
at any one time. Contrary to popular belief, CTCSS does not provide
private communications. If private, interruption-free communication
is desired, use a Digital Cell Phone instead.
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