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18' is the approximate length of a half wave at 11m in free space. You would need to multiply the wavelength desired in feet by the velocity factor of the transmission line in feet to get the proper physical length.

You know 4600 Turbo, I tried to help you understand this about a month ago on the CBRT forum. You must have missed it. Here is a snippet from that post.

=========================

In order for any of the above to be true, you have to go there (velocity factor). For example to make 1/4 or 1/2 wave length lines at 27.185 MHz you would have the following lengths. We will round the length of the wave in free space to 36.2’, keeping in mind that velocity factors for different brands of coax may be different than what I posted.

RG58 .66 vf coax
1/4 = 5.973’
1/2 = 11.946’
Full = 23.982’

RG8X .78 vf coax
1/4 = 7.059’
1/2 = 14.118’
Full = 28.236’

There you go.....

Mopar

<blockquote data-quote="mopar2ya" data-source="post: 88653" data-attributes="member: 87">18&#039; is the approximate length of a half wave at 11m in free space. You would need to multiply the wavelength desired in feet by the velocity factor of the transmission line in feet to get the proper physical length.You know 4600 Turbo, I tried to help you understand this about a month ago on the CBRT forum. You must have missed it. Here is a snippet from that post.=========================In order for any of the above to be true, you have to go there (velocity factor). For example to make 1/4 or 1/2 wave length lines at 27.185 MHz you would have the following lengths. We will round the length of the wave in free space to 36.2’, keeping in mind that velocity factors for different brands of coax may be different than what I posted.RG58 .66 vf coax1/4 = 5.973’1/2 = 11.946’Full = 23.982’RG8X .78 vf coax1/4 = 7.059’1/2 = 14.118’Full = 28.236’ There you go.....Mopar</blockquote>

[QUOTE="mopar2ya, post: 88653, member: 87"] 18' is the approximate length of a half wave at 11m in free space. You would need to multiply the wavelength desired in feet by the velocity factor of the transmission line in feet to get the proper physical length. You know 4600 Turbo, I tried to help you understand this about a month ago on the CBRT forum. You must have missed it. Here is a snippet from that post. ========================= In order for any of the above to be true, you have to go there (velocity factor). For example to make 1/4 or 1/2 wave length lines at 27.185 MHz you would have the following lengths. We will round the length of the wave in free space to 36.2’, keeping in mind that velocity factors for different brands of coax may be different than what I posted. RG58 .66 vf coax 1/4 = 5.973’ 1/2 = 11.946’ Full = 23.982’ RG8X .78 vf coax 1/4 = 7.059’ 1/2 = 14.118’ Full = 28.236’ There you go..... Mopar [/QUOTE]

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