How To Make A High Power 4:1 Balun Info
I built a homebrew 75 meter Double Extended Zepp Antenna,
And I needed a 4:1 Balun , so I decided to Homebrew the Balun also.
Here is how I did it!
I used a 5 inch long piece of PVC Plastic pipe about 5/8 ID and about 7/8 OD , 1 inch OD will work fine.
I wound 12 bifilar Turns using 10 Gauge Solid insulated copper wire, but you can use 12 or 14 Gauge.
I recommend using two different color wires.
I used Black and White from an old piece of 10 Gauge Romex house wire.
If you use 10 Gauge wire the Balun will handle the legal power limit!
Connect the top end of the black wire to the bottom end of the white wire.
This connection point will also connect to the coax shield and ground wire.
Optional – You can also connect a heavy wire as short as possible from this connection point to a ground rod and/or ground system,
A short piece of ½ inch coax with the center and shield connected together at each end would work great.
This puts the whole antenna system at DC ground potential.
Connect one side of your open wire feedline or 450 ohm ladder line etc. to the Top wire “white wire in picture below”
Connect the other side of your open wire feedline or 450 ohm ladder line etc. to the Coax Center and Bottom Wire “black wire in picture below”
After winding the coil I recommend coating it with several coats of clear spray paint “available at Wal-Mart for about $1.00 a can.
This 4:1 balun will work fine from 10 thru 160 meter bands.
NB: There is NO open wire feedline or 450 ohm ladder line etc. connected to the Balun in the picture.
I currently use a 75 Meter Full Wave Delta Loop on the 6 thru 75 Meter bands with a tuner.
I am very pleased with it!, I also currently use a 160 Meter 1/4 wave inverted L antenna.
It will also tune 6 thru 160 meter bands
Copyright by W2HT originally available at http://www.bloomington.in.us/~wh2t/balun.html