Question Of The Day (on topic)
 

"Caveat Lector" wrote in message
news:kBY0f.370$i%.130@fed1read07...


"Brenda Ann" wrote in message
...

"David" wrote in message
...
On Wed, 05 Oct 2005 14:21:26 -0400, dxAce
wrote:



Caveat Lector wrote:

"bpnjensen" wrote in message
oups.com...
Why is it termed "SHORT" WAVE ?

Because it is shorter than medium wave, which in turn is shorter
than
long wave - back when these types of radio signals were the commonly
used wavelengths.

Of course, now with microwaves and picowaves, the name becomes much
less meaningful. In fact, the term H(igh) F(frequency), which seems
to
have replaced SW for many purposes, is not really accurate either.

Bruce Jensen


Very good Bruce -- indeed it is an ancient term carried over to this
very
day

From Wikipedia or google

Shortwave radio operates between the frequencies of 3,000 kHz and 30
MHz
(30,000 kHz) and came to be referred to as such in the early days of
radio
because the wavelengths associated with this frequency range were
shorter
than those commonly in use at that time. An alternate name is HF, or
high
frequency.

Some sources disagree on where shortwave begins. And, NASWA considers
shortwave
to begin at 2000 kHz.

dxAce
Michigan
USA

http://www.iserv.net/~n8kdv/dxpage.htm

All FCC bands break on 3s.


Ah, but can you tell us WHY they break on 3's?




OHHH good question

I suspect its because of the formula
wavelength = 300 / frequency in MHz

So when you divide out the 300/freq

It comes out in even metric units



e.g., ELF Extremely Low Frequency 3 - 30 Hz 100,000 - 10,000 km
SLF Super Low Frequency 30 - 300 Hz 10,000 - 1,000 km
ULF Ultra Low Frequency 300 - 3000 Hz 1,000 - 100 km
VLF Very Low Frequency 3 - 30 kHz 100 - 10 km
LF Low Frequency 30 - 300 kHz 10 - 1 km
MF Medium Frequency 300 - 3000 kHz 1 km - 100 m
HF High Frequency 3 - 30 MHz 100 - 10 m
VHF Very High Frequency 30 - 300 MHz 10 - 1 m
UHF Ultra High Frequency 300 - 3000 MHz 1 m - 10 cm
SHF Super High Frequency 3 - 30 GHz 10 - 1 cm
EHF Extremely High Frequency 30 - 300 GHz 1 cm - 1 mm



I guess, therefore I am

And the 300 in the formula has to do with the speed of light (radio Waves)
299,792,458 metres per second -- for practical purposes
300,000,000 meters per second

CL Guessing twice , confirms I am

Question Of The Day (on topic)
 

Caveat Lector wrote:
Why is it termed "SHORT" WAVE ?



"Short" is relative. The "wave length" is the peak to peak (or
trough to trough) distance between the waveforms as they'd be seen on an
ocilliscope. "Shortwaves" are shorter waves than medium waves, which
are shorter waves than Longwaves. At the inception of the science,
"short" waves were the shortest type used (commonly) at that time.
Today, with cellphones and things using wavelengths that go with
gigahertz frequencies, "short" waves begin to look really long by
comparison.

Tony


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Question Of The Day (on topic)
 

Very good Tony
Wikipedia sez

"Shortwave radio operates between the frequencies of 3,000 kHz and 30 MHz
(30,000 kHz) and came to be referred to as such in the early days of radio
because the wavelengths associated with this frequency range were shorter
than those commonly in use at that time. An alternate name is HF, or high
frequency.
en.wikipedia.org/wiki/Short_wave

As I recall the story At one time the bands below 200 meters were considered
worthless, so they gave the whole range to tha Amateurs
Soon they were sending signals across the atlantic

See 200 Meters and Down By Clinton B. DeSoto.
URL: http://www.arrl.org/catalog/?item=0011

--
CL -- I doubt, therefore I might be !






"Tony Meloche" wrote in message
...
Caveat Lector wrote:
Why is it termed "SHORT" WAVE ?



"Short" is relative. The "wave length" is the peak to peak (or trough
to trough) distance between the waveforms as they'd be seen on an
ocilliscope. "Shortwaves" are shorter waves than medium waves, which are
shorter waves than Longwaves. At the inception of the science, "short"
waves were the shortest type used (commonly) at that time. Today, with
cellphones and things using wavelengths that go with gigahertz
frequencies, "short" waves begin to look really long by comparison.

Tony


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet
News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+
Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption
=----