Beverage antennas - Beverage receiving antennas



Beverage antenna transformers


One wire configuration notes

  • Use separate ground rods, as sharing can cause signal coupling through the connection.
  • Copper coating on steel ground rods disappears with time. Recommend the use of thick wall copper pipe, available in most hardware stores.
  • Keep the Beverage ends away from towers that can re-radiate signals, even if they are not used as transmit verticals.
  • Woods, trees, and vegetation, represent only minimal signal loss reported over many years.
  • Maintain a reasonable constant height above ground except at the ends that may be tapered to ground level. Follow the general contour of the earth, but not every small dip or bump.
  • Beverage antennas "want to work". For best results run a straight line. If a straight run can not be maintained, good results can be obtained with less than perfect.
  • If the Beverage is being used as a single direction terminated antenna, the termination resistance is controlled more by ground conductivity, than wire height. A poor conductivity earth termination would typically be 350 ohms or lower. A more conductive earth termination would typically be 450 ohms or higher.
  • When choosing a termination resistance, avoid the one that gives the minimum VSWR on the band of interest, rather choose the resistance that gives the lowest VSWR over a wide frequency range with a slow increase at the highest frequency end. You may end up with a 1.8:1 VSWR, but you will have found the characteristic impedance of the wire resulting in the best antenna front to back ratio. (The 1.8:1 VSWR would be most likely from a matching transformer to antenna impedance difference)
  • Beverage antennas require the bending of radio waves to work. Lower frequency radio waves bend around mountains, into valleys, and have deeper earth penetration. Poor conductivity earth helps provide earth penetration, and the necessary bending. (Often called tilt angle)
  • It has been said   "A Beverage antenna should be run across a desert with a swamp at each end"   A Beverage will not work well over highly conductive ground or sea water. (The swamp at each end was for your ground rod.)
  • Beverage antennas are low impedance, low Q devices, and do not couple well. Beverage runs can cross each other if a few feet of clearance is allowed.
  • Radial fields radiate energy from the connected vertical. Avoid running a receive antenna, or receive coax across one. (Raised radials radiate more signal energy than in ground radials.)
  • There have problems reported using heat shrink on termination resistors, and multiple reports saying protective covering is not necessary.


Two wire, two direction Beverage notes

  • When using individual wires, maintain the spacing between the two wires. This will help the front to side signal ratio to be near optimum. Treating the wire spacing like transmission line will help the forward and reverse signal levels to be more equal with proper transformers.
  • Slope the wires down to ground at both ends? I tried this at my locations, and at a friends QTH. We found the slope did not change low angle vertical signals compared to a straight drop. We did find that high angle signals were reduced, with longer slopes. Sloping does reduce the impedance and may improve optimal termination resistance for best F/B and pattern. (Most manufactured two wire bi-directional transformers have ground connections set for ~450 ohms impedance (resistance)
  • In cold climates, use a long ground rod as frozen earth does not conduct well.
  • The coax outer shield can pick up signals and compromise the front to back. It is good to have the last 60 or more feet of coax buried near the connection box. This avoids pick up and the capacitance to ground will have a beneficial effect. Coax laying on the ground is usually OK. In cases where the coax is above ground, an effort should be taken to remove common mode signal pick up.
  • Termination of un-used coax is not necessary with accurately placed transformer coil center taps. The two wire Beverage system is a RF version of the old telephone simplex circuit of the 1930's. (Two talk circuits could take place on the same wire pair with electrically center tapped transformers at each end, without cross talk.)
  • Standard published wire lengths for a Beverage from "on line" tables available are 290, 440, 600, 800 feet.
  • Covered wire results in a slowing of radio waves known as velocity factor. A given covered wire length will resonate lower in frequency than uncovered wire.
  • Many find 9 feet above the ground is a good compromise height. (Crossing a roadway not included)
  • I have a close to the ground Beverage antenna in an out of the way area. The pattern and signal to noise ratio are excellent. Roundup was used to remove vegetation from the Beverage run with good results. Deer collisions ceased to be a problem. QRN sometimes noted in solar storms is often less than with other taller Beverage antennas. At 2 feet above ground found a pre-amplifier to be unnecessary
  • Much of the expense of a two wire Beverage is the cost of the wire, and upkeep. 450 ohm cable expense is high, and breakage repair is difficult. WD-1 wire is inexpensive, but repair is somewhat difficult.(Steel strands send me looking for band aids) Both types can deteriorate if water penetrates the insulation. Galvanized electric fence wire spaced about 4-6 inches has an impedance about 600 ohms (depending upon wire size), and is available for about $22.00 for 1/4 mile at farm supply stores. A Western Union splice works well in case of breakage.
  • In the past, tried a 680 ohm two wire Beverage antennas using electric fence wire spaced horizontally, then vertically. No reception difference noted. I found vertical runs much easier with out the need of cross arms.
  • Increased common mode decoupling of the coax cable was often accomplished by addng a coil of many coax turns, combined with added ground rods.. As time passed the number of turns were reduced by adding ferrite cores. Now a popular choke is constructed by winding 6-8 turns of small diameter coax in a 6 inch diameter coil and held together with plastic ties. One mix 31 ferrite 'clamp on' core Amidon 2x31-1081P2, or equivalent is installed over the windings. For increased attenuation use more turns on a larger mix 31 core


  • Propagation note: On 160, look for the auroras. Early after they strike the energy goes to the Earth's poles. At that time, depending upon location, they can give great extended DX, and spotlight propagation.


  •     Beverage antenna transformers

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        BOG antenna notes



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    K1FZ (Bruce Clark) Background highlights:
    Worked in the late 1950's to early 1970's for WLBZ-TV Bangor, Maine as a transmitter engineer.
    Most interesting employment: Worked as the senior maintenance engineer for the Christian Science Monitor syndicate short wave AM radio station in Maine. Transmitter power output was 500 KW. Two high gain TCI model 611 4X4 slewable curtain arrays, topping 363 feet AGL, gave a ERP power of 5 megawatts. (ERP Varied with frequency in use)

    Presently semi retired and working as the Contract Engineer for WERU-FM 89.9 MHZ, listen on line at www.weru.org , a PBS Community Radio FM broadcast station. Music, programs vary with day, and time of day. My favorite is Jazz music 6-8PM weekdays eastern time zone.


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    Bruce-k1fz

    Clark Electronics
    65 Patterson Hill RD.
    Belfast, Maine 04915-7300