Beverage on the Ground

Despite it being a simple antenna, the beverage has not worked out well for my QTH. It also should be noted, a traditional Beverage also did not work out well.

Some Beverage Maths

There is a formulae that alledgedly calculates the effective length of a beverage antenna.

MEL means Maximum Effective Length

MEL =        WaveLength 
           -----------------
                ( 100        )
            4 * (  -      - 1) 
                (  K         )

Where

• Wavelength is in Meters
• K is the Velocity Factor

Simple Insulated 1.2mm Wire

Most PVC wires have a velocity factor of aprox 0.66

So using the above formulae

     1.850Mmz in Meters  
   --------- 
   4*((1.00/.66)-1)

Which becomes

     162
    ----- 
     2.06

Ans: 78.64m 

In theory the effective length for a BOG@160M is 74.64m - longer than that will not add linear amount to the received signal (i.e. diminishing returns).

BOG plan

This is BOG model

The value of 450Ohms is what a traditional beverage uses, some publications site try 250R - most rather suggest measure the voltage and use the appropiate resistance to get an SWR reading of 1:1.

If you are not using RG6, but a 50Ohm coax then you will need to adjust the turns in the Binocular core.

Placement of BOG

The BOG should be as far away from your TX antennai and TX radials. This may be easy if you live on a farm, but sadly most of us do not.

My BOG is in some spare land 40m in front of the TX antenna, which requires a 100m coax run back to the shack - first 50m on LMR400, then on Hardline.

DV3A BOG results

The BOG works well on 80,60,40m - but it does not work well on 160m.

The MEL we calculated (using a very suspect Velocity factor) as 78m, yet the length I installed is only 72m. Could the missing 6m be the reason ?

Or is it the very long coax run, which is causing signal loss, so an already weak signal ?