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  #51   Report Post  
Old August 18th 03, 10:34 PM
Brenda Ann
 
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"erniegalts" wrote in message
...
The 2 metre band extends from 144 to 148 MHz. So if were cutting an
antenna for center of this band at 146 MHz would be 75 / 146 =
0.513698630137. So a quarter-wave vertical would be roughly .513
metres long, or 513 mm. (millimeters) or 20.2244 inches.


This is good math, but usually for a 1/4 wave radiator, 5% is subtracted for
velocity factor, leaving the basic 1/4 wave radiator for 2m at approximately
19".



  #52   Report Post  
Old August 18th 03, 10:46 PM
MJC
 
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If you're looking for an incredibly full-featured Ham Transceiver, look no
further than the Yaesu-817. 2-meter and 6-meter for local use, and then
pretty much everything else for long distance. All you need is a good
portable antenna and tuner and you'll never be out of touch. It's a "legal"
QSL radio with it's maximum 5watt output and can be set up as a base station
(many people have) or slip it into it's case and sling it over your shoulder
for true portability.
But by the way, you need to get your Ham license before you get one.
Reputable Ham dealers will NOT sell you a transceiver unless you furnish
your call sign that matches the address you want them to mail it to.

MJC

"mad amoeba" wrote in message
. net...
I was affected by the recent blackout in North East. That got me thinking

of
how would
one communicate during such an event. Electricity including phones were
out.
Cellular phones didn't work either. So the only way of receiving

informaiton
was by radio.
My old Sony wm-gx670 did quite nicely. But what if I would need to
communicate with
my relatives or even cops to let them know of an emmergency. If
telephone/cellular/internet
are not available what are my other options? Let's say people I want to
communicate with
are more than several miles away in an urban area. That makes CB radio
useless--right? So
then as far as I understand using ham radio is my only option. With that

you
can either get in
touch with your relatives directly, provided they have ham radio as well,

or
you can call
some person in an area without blackout and tell them to call
police/ambulance etc if that's
what you need.

Not knowing much myself about scanners/shortwaves/hams myself I want to

ask
you guys
with more experience if the below piece of equipment is what I need.

As far as I understand this is an handheld ham radio which also functions

as
a scanner and
can also receive on a shortwave band. So it will allow me to communicate
with people
far away even in urban setting, it is portable and it will also allow me

to
monitor news as
well as police/firefighters etc. Am I right?

Yaesu VX-2R
http://www.universal-radio.com/catalog/ht/0176.html

the price is kind of steep but for all-in-one product I would be willing

to
pay it.




  #53   Report Post  
Old August 18th 03, 10:59 PM
Perry Noid
 
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It's simple to throw together a set of field telephones from 2 common
type American telephones (complete telephones). Simply connect the red
and green wires with at least a 9 volt battery (up to 48 volts DC) in a
big loop, but you'll have to play around with finding and adding the
right value resistor to the loop to limit the volume. DC volts has a
limited range tho. It's very complicated however, making a phone ring,
so for your ringer you can salvage a couple door bells (or other DC volt
device) to act as your ringer with the switch for each at the opposing
end. You can pick up an ordinary phone at some dollar stores for about
$7 each. Since you don't have to modify the phone itself, you can easily
return it to common use.
  #54   Report Post  
Old August 18th 03, 11:58 PM
Dee D. Flint
 
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"Brenda Ann" wrote in message
...

"KB9WFK" wrote in message
news
How do you define "a few miles"? Like I said in another post, I can
go 18 miles on my 7 Watt 2 Meter HT. Put a decent antenna on it and I
can talk a lot further. Our club repeater has over a 50 mile range
and only puts out 25 Watts.
Depending on usage, our repeater can go 4 or 5 days with no outside
power.

KB9WFK


I was able to hit a 'local' repeater with my HTX-202 using only the stock
antenna from a distance in excess of 50 miles. This was from a place in

the
valley west of Salem, OR to a hillside east of Vancouver, WA. This was

using
5 watts for clean copy. If one station is in a good location, even an HT
can get very good range on 2m.



The key element is antenna height. If the repeater antenna is high enough,
you can get quite good distances. Or if your own antenna is high enough,
same thing. Naturally if both antennas are high, possible distances
increase.

On the other hand, rubber duck antenna to rubber duck antenna at ground
level, 2 to 5 miles will generally be the limit.

Dee D. Flint, N8UZE

  #55   Report Post  
Old August 19th 03, 12:01 AM
erniegalts
 
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On Tue, 19 Aug 2003 06:34:35 +0900, "Brenda Ann"
wrote:


"erniegalts" wrote in message
.. .
The 2 metre band extends from 144 to 148 MHz. So if were cutting an
antenna for center of this band at 146 MHz would be 75 / 146 =
0.513698630137. So a quarter-wave vertical would be roughly .513
metres long, or 513 mm. (millimeters) or 20.2244 inches.


This is good math, but usually for a 1/4 wave radiator, 5% is subtracted for
velocity factor, leaving the basic 1/4 wave radiator for 2m at approximately
19".


True, but the formula is only a rough guide anyway. Even at much
lower frequencies there are a few variables, and at VHF and UHF
wavelengths antenna length can be very critical.

On Australian UHF CB band can make a nice little handheld 3 element
Yagi out of a UHF socket and an old coathanger which will give around
3 or 4 dB gain. [Perfectionists would probably use aluminum, copper,
or even silver wire, though. ]

Passing thought: Will Brock rush into print claiming that copper is a
better conductor than silver? :-)

Corner reflectors or arrays usually a better choice for more gain,
although even high gain rhrombics with theoretical 25 dB gain are a
manageable size at UHF if looking for really reliable point to point
communication.

Can make up 9 DB collinear omnidirectional verticals for UHF from RG-8
coax and plastic electrical conduit, although fiberglass is better.
Not much margin for error at these frequencies, though.

Can make a pretty decent UHF TV antenna using an phased array made up
of a chicken wire reflector and beer or soft drink cans as elements.
Not as good as an 18 element Yagi, but cheap and easy alternative.

Antennas can be great fun to play with. Was raised in a rural area,
and when TV first became available some local farmers were spending a
lot of money for tall masts and high gain Yagis to pull in a good VHF
signal.

However, I was highly amused when one old farmer who knew no antenna
or propagation theory whatsoever pulled in nearly as good as signal by
using a junked bedspring from a double bed, which he mounted on an old
apple crate and leaned against a tree, using rubber from old inner
tubes as insulation. He was just using flat 300 ohm lead in, split
the antenna end and fitted with alligator clips, and played around
with trial and error until found the proper feedpoint. He had no
terrain advantage over the others and doubt if an expensive Yagi at a
similar level would have worked much better.

His neighbors who had spent a lot more on their antennas weren't quite
as amused, though. :-)

When I was a kid, a lot of amateurs used "home brew" equipment, but
most amateurs these days seem to take their transceiver back to the
dealer for anything more complicated than replacing an incandescent
bulb or an LED indicator. :-)

The radio scanner enthusiast might consider building a large discone
antenna if has the space. No gain, but good SWR over many decades of
frequency range. Simple to build, size of disk and skirt not
especially critical as long as large enough to cover lowest frequency
of interest. Most libraries should have a reasonably current ARRL
Antenna handbook.

erniegalts







  #56   Report Post  
Old August 19th 03, 12:33 AM
erniegalts
 
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On Mon, 18 Aug 2003 18:22:00 -0400, "Ralph Mowery"
wrote:

But by the way, you need to get your Ham license before you get one.
Reputable Ham dealers will NOT sell you a transceiver unless you furnish
your call sign that matches the address you want them to mail it to.


There are not very many reputable ham dealers if that is the case. Many
will sell without asking if you are a ham. There is no US requirement that
you have a license to buy a transceiver , just to transmitt on one.

Probably, but is it a good idea to have something that is illegal to
use in most cases? Most hams are quite protective of their band
allocations and spend a lot of time tracking down illegal users.

Same thing happened here when UHF CB was introduced. CB sets on HF
and UHF had to be licensed at the time. Most people who went on UHF
when it was introduced were former users of HF Citizens Band and were
determined to keep the idiots and children off UHF.

Those who didn't use registered call signs, or otherwise didn't stick
to regulations found that those with call signs would simply refuse to
answer their transmissions. Having seen the 27 MHz service in cities
deteriorate to the point where it wasn't useful most of the day,
users of the new UHF service were determined that it didn't go the
same way.

Unlicensed operators were usually quickly reported to Department of
Communications, which is Australian equivalent of the F.C.C.

There were even viligantie groups doing transmitter hunts for illegal
operators. These were often persuaded to sell their sets and go back
to the 27 MHz "chicken band" if they couldn't bother to get a license
or use proper procedure.

Sometimes their equipment was sabatoged. However, am not about to
give advice how this can be done, of course. Not that I would stoop
to such activity, but some users enjoyed it. :-)

If really interested on using amateur radio equipment for emergency
use, should know at least some theory and practice. ....And as long
as going to do this, why not learn the regulations as well and get a
license?

erniegalts





  #57   Report Post  
Old August 19th 03, 12:47 AM
Ralph Mowery
 
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There are not very many reputable ham dealers if that is the case. Many
will sell without asking if you are a ham. There is no US requirement

that
you have a license to buy a transceiver , just to transmitt on one.

Probably, but is it a good idea to have something that is illegal to
use in most cases? Most hams are quite protective of their band
allocations and spend a lot of time tracking down illegal users.


Guess that it is a differant point of view. Mine is that if someone pays
money for a transceiver (especially a low band one so they can practice
copying the code) they will have an investment and reason to get their
license so they can operate all the bands.


  #58   Report Post  
Old August 19th 03, 12:50 AM
Ralph Mowery
 
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They cannot refuse to sell you the radio merely because you have no

license.
Back when licenses took 3 months to arrive (which wasn't all that long

ago),
many people purchased their gear and set up their station while they

waited
for the license.

Dee D. Flint, N8UZE


Even now as many take the test at hamfests and get the results back in a few
days , it is nice to buy a rig at the hamfest and get it set up so you can
use it in less than a week.

DE KU4PT



  #59   Report Post  
Old August 19th 03, 01:21 AM
Perry Noid
 
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erniegalts wrote:

Wouldn't consider it "very complicated" to make a phone ring as only
need to provide around 60 volts AC at 16 cycles or so.

erniegalts


Just what percentage of us do you think could do that? and from DC
power? For about 98% of us it is "very complicated", and the one
electronics tech among us doesn't need any help.
  #60   Report Post  
Old August 19th 03, 03:09 AM
Gunner
 
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On Tue, 19 Aug 2003 00:21:16 GMT, (Perry Noid) wrote:

erniegalts wrote:

Wouldn't consider it "very complicated" to make a phone ring as only
need to provide around 60 volts AC at 16 cycles or so.

erniegalts


Just what percentage of us do you think could do that? and from DC
power? For about 98% of us it is "very complicated", and the one
electronics tech among us doesn't need any help.


Chuckle..I made up a private phone system when I was 13. Rang and
everything.

Then I discovered "field phones" Way much better.

Gunner

Have you noticed how these enviros have become alarmed by the
proliferation of large carnivores in the boonies? I saw one remark to
the effect that bears, for example, do not seem to know their place on
the "food chain." Why should they? Only man comes up with ideas like
a food chain, and with man the idea only makes sense because man is
armed. Without his weapons, man is by no means at the top of any food
chain. On the contrary, he is down in fourth or fifth spot, depending
upon the environment in which he lives. Primitive man was under no
illusions about this, nor are the backwoods folk in India today. To a
tiger, man is a morsel, as these unarmed joggers seem to be to a cougar,
upon occasion. Man is man because he is always armed. That is something
they do not teach in kindergarten, nor for that matter in high school. A
youth becomes a man when he is first presented with his own personal
weapon. That is his right of passage, and those who do not understand
that are questionable members of a free society.
- Jeff Cooper's Commentaries, Vol. 9, No. 7, July, 2001
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