I am looking for a .xls spreadsheet (or something that works under LINUX),
to calculate the equations for matching common maritime mobile HF whip
antennas:

8 ft
10 ft
15 ft
23 ft
40 ft (backstay, approx 5/8 on 20 Meters)

I want to calculate the matching parameters including voltages generated
in the tuner for the 1.8 3.5 7 10.1 14 21 28 MHz ham bands and the 2 4 6 8
12 16 and 22 MHz marine bands.

The ARRL ANTENNA HANDBOOK, 18th edition, chapter 18, has some equations
and a table of calculated values for a 8 ft whip on ham bands. I wish to
duplicate the calculations and figure out the voltage maximums for
component values for, say, 100 W key down power.

Take for example the 1st row of the table:

BASE LOADED 8ft whip
F=1.8 MHz
Loading L = 345 uH
Rc Q=50 = 77 ohms
Rc Q=300 = 13 ohms
Rr =0.1 ohms
Feed R = 23 ohms
Matching L = 3 uH

Now at 1.8 MHz
XL of 345 uH = +j3902 ohms

Do I calculate the current from P=I*I*R so for
Rr = 0.1 ohms, I = sqrt(100/Rr) = 31.6 A
so V XL is I*R = 31.6*3902 = over 123 KV? (seems excessive)

or do I use the R values of 77, 13, or 23 ohms? (4.4 KV, 57 KV, 8.1 KV )?

Do I multiple all RMS voltages by sqrt(2) to convert RMS to PEAK?

Greg
VE0ACR
gblair _at_ sympatico _dot_ ca

On Fri, 04 Feb 2005 13:46:50 -0500, Spam Fighter wrote:

I am looking for a .xls spreadsheet (or something that works under
LINUX), to calculate the equations for matching common maritime mobile
HF whip antennas:

8 ft
10 ft
15 ft
23 ft
40 ft (backstay, approx 5/8 on 20 Meters)

I want to calculate the matching parameters including voltages generated
in the tuner for the 1.8 3.5 7 10.1 14 21 28 MHz ham bands and the 2 4 6
8 12 16 and 22 MHz marine bands.

The ARRL ANTENNA HANDBOOK, 18th edition, chapter 18, has some equations
and a table of calculated values for a 8 ft whip on ham bands. I wish
to duplicate the calculations and figure out the voltage maximums for
component values for, say, 100 W key down power.

Take for example the 1st row of the table:

BASE LOADED 8ft whip
F=1.8 MHz
Loading L = 345 uH
Rc Q=50 = 77 ohms
Rc Q=300 = 13 ohms
Rr =0.1 ohms
Feed R = 23 ohms
Matching L = 3 uH

Now at 1.8 MHz
XL of 345 uH = +j3902 ohms

Do I calculate the current from P=I*I*R so for Rr = 0.1 ohms, I =
sqrt(100/Rr) = 31.6 A so V XL is I*R = 31.6*3902 = over 123 KV? (seems
excessive)

or do I use the R values of 77, 13, or 23 ohms? (4.4 KV, 57 KV, 8.1 KV
)?

Do I multiple all RMS voltages by sqrt(2) to convert RMS to PEAK?

Greg
VE0ACR
gblair _at_ sympatico _dot_ ca

I have it all sorted out. The 2002 ARRL Handbook has a similar
table complete with voltages. However, there was a mistake in the
text. Working backwards from the stated result, we found the text used a
coil capacitance value of 2.5 pF while stating they we using 2 pF. They
also assume Rg (ground) is zero. I can duplicate their table and have
calculated the data I was after for the other whip lengths.

I have a .xls spreadsheet I can email anyone who is interested.

Greg Blair
ve0acr _at_ rac _dot_ ca

I have a .xls spreadsheet I can email anyone who is interested.

Greg Blair
ve0acr _at_ rac _dot_ ca


I am interested, but you may find it more efficient to post it on a
website for download.

Thanks
Buck
N4PGW

na4fm (I)
at (really)
towncorp (don't)
dot (like)
net (spam)
--
73 for now
Buck
N4PGW

On Sun, 06 Feb 2005 23:05:28 -0500, Buck wrote:


I have a .xls spreadsheet I can email anyone who is interested.

Greg Blair
ve0acr _at_ rac _dot_ ca


I am interested, but you may find it more efficient to post it on a
website for download.

Thanks
Buck
N4PGW



http://www3.sympatico.ca/gblair/whip.xls

notice the "www3" not the usual "www" in the URL.

Enjoy!

Greg Blair
ve0acr

http://www3.sympatico.ca/gblair/whip.xls

notice the "www3" not the usual "www" in the URL.

Enjoy!

Greg Blair
ve0acr

The URL worked but the xls didn't It came up unrecognizable and
looks like hyroglyphics

--
73 for now
Buck
N4PGW

On Mon, 07 Feb 2005 19:42:39 -0500, Buck wrote:



http://www3.sympatico.ca/gblair/whip.xls

notice the "www3" not the usual "www" in the URL.

Enjoy!

Greg Blair
ve0acr

The URL worked but the xls didn't It came up unrecognizable and
looks like hyroglyphics

It was created in LINUX'S GNUMERIC spreadsheet and might have been saved
as a GNUMERIC format spreadsheet.

I just saved as an EXCEL 97 spreadsheet document and reloaded it to the
server.

Try again.

On Tue, 08 Feb 2005 07:56:23 -0500, Spam Fighter
wrote:

On Mon, 07 Feb 2005 19:42:39 -0500, Buck wrote:



http://www3.sympatico.ca/gblair/whip.xls

notice the "www3" not the usual "www" in the URL.

Enjoy!

Greg Blair
ve0acr

The URL worked but the xls didn't It came up unrecognizable and
looks like hyroglyphics

It was created in LINUX'S GNUMERIC spreadsheet and might have been saved
as a GNUMERIC format spreadsheet.

I just saved as an EXCEL 97 spreadsheet document and reloaded it to the
server.

Try again.


Thank you,
Everything works this time

73 for now...
--
73 for now
Buck
N4PGW