Most hams are familar with the center fed, half wave dipoles and
inverted vees that are very popular and easy to build. This formula will give
you a starting point to make these antennas. There are several factors that
affect the resonant frequency of any antenna. Some of these factors are: the
height above ground, nearby structures
.
If you've ever used some of the other antenna design programs you
may realize that the formula for these types of antennas vary from about 470/f
Mhz to 495/f MHz depending on the band and the height above ground!
Fortunately there is a standard( ARRL hand book )formula is used
as a starting point for your antenna. For a center fed, wire dipole, this
formula is 468 / frequency in megahertz. I've always cut the antenna a few
inches longer which would allow me to trim the antenna in order to obtain a
match.
The inverted vee has always been about 5% shorter than a dipole
at the same frequency so I used that as a constant in the calculation.
Enter the formula for the antenna calculation
Divided by Freq MHz
Percent smaller for the Inverted Vee
Your dipole's length is feet
Each leg of the dipole is feet
Your Inverted Vee's length is feet
Each leg of the Inverted Vee is feet
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Q= IS illegal to use my Ham Rig on CB
A= Using your amateur radio
to transmit on non-ham and/or non-MARS frequencies is illegal,
even if you are properly licensed and/or authorized to
operate in one or more non-ham bands.
It doesn't matter if you're a deputy sheriff , Ship Captain , a firefighter , or an FBI agent.
The FCC rules are clear on this. Non type-accepted equipment ( consumer
amateur gear) may not be used on these frequencies.
To be legal, you must get a type accepted radio
(like a Motorola are GE equipment ) and modify it to operate on Ham Frequencies - not the
other way around.
THE HAM CODE
Considerate... Never knowingly operates in such a way as to lessen the
pleasure of others
Loyal... Offers loyalty, encouragement and support to other amateurs, local
clubs, through which Amateur radio in the United States is represented
nationally and internationally.
Progressive... With the knowledge abreast of science, a well built and
efficient station and operation above reproach.
Friendly... Slow and patient operating when requested; friendly advice and
counsel to the beginner; kindly assistance, cooperation and consideration for
the interests of others. These are the hallmarks of the Amateur spirit.
Balanced... Radio is a avocation, never interfering with the duties owed to
family, job, school, or community.
Patriotic... Station and skill always ready for service to country and
community.
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