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Originally Posted by Russ D
I'll try the dipole suggestion, although I though each half of coax would need to be 7 feet long, not 8 and a half as you've said?
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No 7 is too short!
I knwo a dipole for 28MHz is about 16 foot 7 inches, it can be worked out from the formula 300/f
f in your case is 27MHz, you must then take away the correction factor for the difference between the velocity factor of the wire and free space. It usually works out about 95%
To work it out in good old feet and inches use 495/f , my 28.5 Mhz example is 17.403 feet, multiply by 0.95 for the velocity factor and you get 16.533 feet, divide by 2 to get 8.266 feet per side. Your dipole being 27MHz will be slightly longer, and also remember the length is affected by the wavelength it's located above ground, the figures are for free space calculations above ground.
PS: The 300 in the equation comes from the speed of light 3x10-8 meters per second in free space, the 95% is cos its travelling in a wire.