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David April 11th 05 03:04 PM

On Mon, 11 Apr 2005 04:44:02 -0400, dxAce
wrote:

''...for example, let's say you want to pick up Radio Havana Cuba's
ever popular 9820 kiloHertz frequency... First let's calculate 9820
kiloHertz 's wavelength... easy too... Wavelength in meters, equals
the constant 300, divided by the frequency in megaHerz... which is 300
divided by 9.820, and that equals... let's see 30.54 meters
wavelength...''


So... what did that have to do with your original statement?

dxAce
Michigan
USA

''Meters times MegaHertz equals 300''.



Brian Hill April 11th 05 03:37 PM


"David" wrote in message
...
On Mon, 11 Apr 2005 04:44:02 -0400, dxAce
wrote:

''...for example, let's say you want to pick up Radio Havana Cuba's
ever popular 9820 kiloHertz frequency... First let's calculate 9820
kiloHertz 's wavelength... easy too... Wavelength in meters, equals
the constant 300, divided by the frequency in megaHerz... which is 300
divided by 9.820, and that equals... let's see 30.54 meters
wavelength...''


So... what did that have to do with your original statement?

dxAce
Michigan
USA

''Meters times MegaHertz equals 300''.



Hello Mr. Meterhertz. How are you today?

B.H.



[email protected] April 11th 05 04:46 PM

Yeeeeee Hawwwww!,,,, one little simple question the guy asked and so
many different answers.I replaced a couple of eaves boards on my house
not long ago.Now,if a board is too long,I know what to do with it,but if
that damn board is too short,that is a problem.Say there,Cousin
Anders,don't forget to tell them pretty wimmins over there in Danske
that old Hansom Larry (that's me,y'all wimmins) loves them.
cuhulin


dxAce April 11th 05 05:19 PM



David wrote:

On Mon, 11 Apr 2005 04:44:02 -0400, dxAce
wrote:

''...for example, let's say you want to pick up Radio Havana Cuba's
ever popular 9820 kiloHertz frequency... First let's calculate 9820
kiloHertz 's wavelength... easy too... Wavelength in meters, equals
the constant 300, divided by the frequency in megaHerz... which is 300
divided by 9.820, and that equals... let's see 30.54 meters
wavelength...''


So... what did that have to do with your original statement?

dxAce
Michigan
USA

''Meters times MegaHertz equals 300''.


So if I take 10 meters, multiply it times 10 MHz. and I'll get 300?

You'd better check that obscure math.

dxAce
Michigan
USA



Anders Henriksen April 11th 05 06:00 PM

Anders Henriksen wrote:

wavelength [m] = 285/f[MHz] = wavelength = 285/160.89 = 1,771 m

A dipole should normally be half of this lenght: 1,771/2 = 0,886 m, that
would be 2.91 feet. Each leg of the dipole should be 44.3 cm or 1.45 feet.

I am not sure I remember the factor between metres and feet correctly,
but the picture should be clear to all.


HA HA! Didn't take me long to show off my 'tardism... "," should be
replaced by "."

Regards,
Anders Henriksen
oz7ahr, Denmark

Michael A. Terrell April 11th 05 06:09 PM

RHF wrote:

DF,
.
And the 'original' Question Is (Was) :
" formula for calculating the length of a full-wave antenna wire "
.
"How Do I" ? Calculate the Length of Wire I need to build a Wire
Antenna ?
http://groups.yahoo.com/group/Shortw...a/message/2884
.
This webpage does a very good job of providing an answer.
- - - How Do I Find the WaveLength of a Frequency ? - - -
.
GoTo= http://www.radiomods.co.nz/radiomath.html
.
IN THEORY - The Numbers Are :
Meters = 300 Divided by Frequency in MHz
Feet = 984 Divided by Frequency in MHz
Inches = 11,811 Divided by Frequency in MHz.



Not "In theory" but in free space.


IN PRACTICE - {The-Real-World} - The Numbers Are :
Meters = 285 Divided by Frequency in MHz
Feet = 936 Divided by Frequency in MHz
Inches = 11,235 Divided by Frequency in MHz.



This is caused by the propagation delay in the conductor the antenna
is made of. In other words, the wire is measurably slower that free
space. This is speced as the "Propagation Delay" and is stated as a
percentage. Look at the data on Coaxial cable for examples.


Other Questions - Asked-and-Answered :
* How do I find the frequency of a wave length ?
* How do I Calculate the Length of Wire I need to build a Wire
Antenna. ?
[ You must use the following Math to Correctly Cut an Antenna. ]
- One {Full} Wave Length (WL)
- Three-Quarter Wave Length (3/4 WL)
- Five-Eighths Wave Length (5/8 WL)
- One-Half Wave Length (1/2 WL)
- One-Quarter Wave Length (1/4 WL)
- One-Eighth Wave Length (1/8 WL)
.
FULL WAVE LENGTH WIRE (WL) ANTENNA
IN FEET = 936 DIVIDED BY FREQUENCY
.
Plus the Age Old - How Do I Convert :
* Meters-to-Feet ?
* Feet-to-Meters ?
.
.
iane ~ RHF



--
Former professional electron wrangler.

Michael A. Terrell
Central Florida

dxAce April 11th 05 10:01 PM



David wrote:

On Mon, 11 Apr 2005 12:19:14 -0400, dxAce
wrote:



David wrote:

On Mon, 11 Apr 2005 04:44:02 -0400, dxAce
wrote:

''...for example, let's say you want to pick up Radio Havana Cuba's
ever popular 9820 kiloHertz frequency... First let's calculate 9820
kiloHertz 's wavelength... easy too... Wavelength in meters, equals
the constant 300, divided by the frequency in megaHerz... which is 300
divided by 9.820, and that equals... let's see 30.54 meters
wavelength...''

So... what did that have to do with your original statement?

dxAce
Michigan
USA

''Meters times MegaHertz equals 300''.


So if I take 10 meters, multiply it times 10 MHz. and I'll get 300?

You'd better check that obscure math.

dxAce
Michigan
USA


If you know the frequency in megaHertz, divide it into 300 to get the
wavelength in meters.
Jesus ****!! This is goddam kid's stuff from the '50s.


Sure thing 'tard boy... but ''Meters times MegaHertz equals 300''... NOT!

You just keep trying, and please... take your meds!

dxAce
Michigan
USA



dxAce April 11th 05 10:03 PM



Brian Hill wrote:

"David" wrote in message

Jesus ****!! This is goddam kid's stuff from the '50s.


Now that was a terrible thing to say Mr.Meterhertz. I don't think
Stanford.edu would like that kind of talk.


Stanford? Well hell, that sure explains a lot... no wonder he's a scared little
girl.

dxAce
Michigan
USA



Brian Running April 11th 05 10:09 PM

So if I take 10 meters, multiply it times 10 MHz. and I'll get 300?

No, but the 10-Meter band is not 10 MHz, either.

[email protected] April 11th 05 10:13 PM

Nawww,Cmd Buzz Corey,,, I do things the right way.Measure twice (but in
my case,I measure a bunch of times and even then,once in a great while,I
mess up :{) and cut once.I am not perfect,but almost so.
cuhulin




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