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Many people have questions about two-way
radio and short-wave radio listening. Questions
range from "How far can I talk to someone else
using a handheld radio?" to "How can I
talk around the world?"; This section of VERO
two way radio Online answer these and other common
questions. We know that many of you are Internet
visitors who are unfamiliar with radio technology.
This section, together with the Welcome section
of VERO Radio Online can answer your general questions
about general radio technology.
Questions answered in this FAQ:
Q. I saw an ad for two VHF/UHF radios
for use in my business. Over how great a distance
will these radios communicate?
Q. What if I need to talk over a greater
range? I need to communicate over about 20 miles
with handheld radios-how can I do this?
Q. What is the difference between a
VHF handheld and a UHF handheld?
Q. How much power do I need in my two-way
radio system?
Q. Why should I use handheld radios
instead of cellular phones?
Q. I live in an apartment (or condo).
Can I still do something in ham radio?
Q. Do I really need to get a license?
Can't I just buy a radio and start talking?
Handheld Radios
Q. I saw an ad for two VHF radios for use
in my business. Over how great a distance will these
radios communicate? Top
A. VHF handheld radios usually operate in the 1
to 2 watt range and sometimes up to as much as 5
watts output (but note that higher power levels
will more quickly drain your batteries). These radios
might provide useful radio coverage at ground level
over about 1/2 mile, assuming that one or both radio
users are inside buildings or structures. Outside,
coverage may be more than 1 mile if relatively free
of obstacles.
Q. What if I need to talk over a greater
range? I need to communicate over about 20 miles
with handheld radios-how can I do this?
Top
A. How much greater range do you really need? It
may be possible to use a telescoping antenna on
a VHF handheld radio, greatly increasing your usable
range versus that provided with the short flexible
antenna typical of most handhelds. You may also
have the option of installing an outside antenna
at one end of the link. Depending on your desired
coverage area, you might see a 2 to 5 mile range
- or more if one end is high above the other and
clear of obstacles. If you still need longer range,
you should consider using a "repeater".
A repeater is a specially built receiver and transmitter
pair that receives signals from low power handheld
or mobile radios and retransmits them using a better
antenna and more transmitter power. Consequently,
the repeater can extend the range of a typical handheld
by great distances. The actual distance depends
on the system design and location. Where a repeater
is located high atop a mountain, it may be possible
to communicate to another station 100 miles away.
For commercial users, you can rent use of an existing,
shared repeater system. You can also enquire about
using Specialized Mobile Radio Service (or SMR)
systems that operate similar to the basic repeater
and provide coverage over wide areas. Look under
"Radio, 2-way" in your telephone directory.
Q. What is the difference between a VHF
handheld and a UHF handheld? Top
The terms "VHF" and "UHF" refer
to parts of the radio spectrum. "VHF"
refers to radio signals in the 30 Mhz to 300 Mhz
range and includes many public safety and business
communications systems; FM broadcasting, TV channels
2-13 and aviation radio. "UHF" refers
to radio signals in the 300 Mhz to 3000 Mhz range.
Until a decade or two ago, it was technically difficult
or more expensive to build radios in this frequency
range. As demand for radio usage has increased,
the technology has improved and the costs of UHF
radios have reduced so that VHF radio applications
have moved or are moving to UHF. You will also find
cellular phone service in this part of the radio
spectrum; at the upper end you will find consumer
microwave ovens and microwave "wireless cable"
TV systems.
Q. Why should I use handheld radios instead
of cellular phones? Top
A. A cellular phone is ideal for making phone calls.
It is not ideal for short range point to point communications
since cellular is expensive. Further, if you need
to make frequent short contacts, cellular requires
that you dial the phone number and wait for the
connection to be established, a delay of up to 30
seconds for every call that you make. With a hand
held radio you push the talk button and you talk
without delay. If you need to have several people
talking to each other at the same time, you can
set up several two way radios on the same frequency.
Each time one user speaks, everyone on thesame frequency
hears that person.
Q. How much power do I need in my two-way
radio system? Top
How much power you need depends on how you plan
to use the radio system. As a general rule, you
should always use the least amount of power necessary
to establish your communications. This reduces interference
to other users (and they likewise reduce interference
to you) when the radio frequency is used again in
geographically local areas. Handheld radios normally
operate in the 1 watt to 5 watt range. Cellular
phones dynamically adjust their power levels, according
to directions from the local cellular base station.
Handheld celphones operate between 40 milliwatts
and 600 milliwats (6/10ths of one watt); mobile
cellular phones operate from 40 mw up to 3.0 watts.Mobile
2-way radio equipment operates, typically from 5
watts up to 50 watts, andsometimes as high as 100
watts output. The power level of the equipment is
determined by the needs of the system.
Q. I live in an apartment (or condo). Can
I still do something in ham radio?
Top
A. You sure can! Obviously, when you live in an
apartment you will have restrictions on your ability
to install radio antennas. Yet there are several
steps you can take to enjoy ham radio. First, if
your interest is primarily in local area communications,
you can use VHF and UHF radio equipment. Often,
you will only need a handheld radio to access a
local voice or packet data radio repeater. Some
apartment-bound radio operators install small beam
antennas inside. I know one ham operator who operates
amateur television equipment - literally transmitting
color TV signals from his apartment. Fortunately
for him, he had a window that opened up to face
a nearby mountain peak that was home to an amateur
radio TV repeater system. So his signals were then
retransmitted over a very wide area enabling him
to communicate using full motion, full color and
sound television signals. If you wish to operate
on the shortwave bands (known as "HF"),
there are several alternatives you can consider:
(1) you can install a wire antenna on the ceiling
of your apartment and operate at reduced power levels
to avoid causing interference to neighbors caused
by your antenna being close to their TV or sterio;
(2) install a dipole antenna for the higher HF bands
in a balcony area;
(3) string an "invisible" wire antenna
made from small gauge wire from your apartment to
a nearby support such as a tree;
(4) use a closed tuned loop antenna mounted in a
balcony;
(5) set up a good mobile radio installation for
the HF bands and operate from your vehicle. All
of these methods can prove very effective at providing
HF communications for persons having limited space
for antennas. I know of two amateurs who asked for
and received permission to extend a single wire
antenna across the roof of their apartment building
and were thereafter able to enjoy HF amateur radio
operation.
Q. Do I really need to get a license? Can't I just
buy a radio and start talking? Top
A. Yes, you really need to be licensed. First,
operating high power radio equipment poses certain
safety hazards and the licensing process ensures
that you know something about radio frequency safety.
Second, a transmitter operator needs to know how
not to interfere with other users; how to locate
and make contact with other users at the appropriate
times; and how to adjust and operate the equipment.
Third, turning on a radio transmitter is roughly
equivalent to turning on a flashlight in a dark
room - in other words, you are easy to find. If
you operate without a license, you will be caught.
This can result in large fines (such as $10,000),
jail time and confiscation of your radio equipment.
In short, get a license. |