ANTENNAS FOR 100 POUND DXPEDITIONS
9 LONG BUDDIPOLE The Standard Buddipole system used just the compliment of parts included in the Buddipole Deluxe Package (plus TRSB). This chapter discusses options for antenna designs when extra components or substitute components are used. 9.1
Differences between the Standard Buddipole and Long Buddipole One of the biggest problems with the antennas constructed from the Standard Buddipole system is the length of the whips. The 5.5 foot stainless steel whips are just too short to make good antennas on the lower bands. Buddipole offers longer whips into two forms: •
Shock-cord whips – These whips are constructed from solid aluminum pieces that are held together by a stretchy nylon rope in the middle. Similar to tent poles, these whips can be pulled apart for storage, or strung together to make a virtually unbreakable radiator. The advantages of these whips is their sturdiness; the disadvantage is they cannot be adjusted as finely as a regular whip. Costs range from $36 to $60 depending on length.
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Long telescopic whips – These whips extend to 9 feet 4 inches in length, nearly double the standard stainless steel whip. They collapse to about 22 inches so they can be stored and packed with other Buddipole parts. They are surprisingly resilient for their length. A long telescopic whip is $18 as of this writing.
The lengths of elements can also be increased by adding extra antenna arms. Each 22 inch aluminum piece not only adds length to an element but also adds bandwidth as the pieces are 0.75 inches in diameter (instead of the much smaller diameter whip sections). The designs below will use the long telescopic whips instead of the shorter stainless steel whips. Designs will also incorporated 0, 1, or 2 arms as necessary to eliminate the need for loading coils. No coils are used in the following antenna system designs! Each antenna has one radial running down from the feed point at an angle of 45 degrees (or less). In practice, the antenna is constructed so that the vertical radiator is full-sized based on the formula 234/f and the length of the radial is adjusted to bring the antenna into a good match for 50 ohms. 9.2
Buddipole full-sized vertical with 1 radial 8 feet
9.2.1 Buddipole full-sized vertical with 1 radial for 10m at 8 feet The vertical for 10 meters appears below. We assume a whip can be used as the radial so it has a large diameter. Here is the model data for this antenna.
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