Build a 4:1 Balun...
Need 2 toroids, 2- 28 inches of solid wire,
2 small zip ties, soldering kit, a 200 ohm resister.
2 small zip ties, soldering kit, a 200 ohm resister.
Here is a project that does not cost an arm and a leg.. and you
do it yourself or have a ham buddy come over do it together.
Put together three 4:1 Baluns. One was a 9 turn wrap and the
other two were 12 turn wraps. Dave KD9HJJ wrapped the last
one with the 12 turns. They all checked good with the resistance test.
other two were 12 turn wraps. Dave KD9HJJ wrapped the last
one with the 12 turns. They all checked good with the resistance test.
The biggest concern to me was the dipole settings. It seems the more
you read, the more confusing it gets. Graphs show the different
locations for the balun. To me, the key was the 1/3 - 2/3 setting.
But I did not take my own advice and used figures from one web
site.. after too many trims, there was not enough wire.
you read, the more confusing it gets. Graphs show the different
locations for the balun. To me, the key was the 1/3 - 2/3 setting.
But I did not take my own advice and used figures from one web
site.. after too many trims, there was not enough wire.
Found a few youtube sites that had setting for length... found out the
hard way again. Finally found one that set one up and showed the
analyzer results. For the OCF Off Center Fed Dipole, he used 88.4
feet on one side and 44.5 feet on the other. Some of this is factoring in
the size of the wire used.. calculations for velocity factor. That is
what I used and all three, regardless of the number of windings.
Letting you know that I used a L 15 toroid on one and the others were
140-43.. not too expensive. 6 with shipping at $25.
A lot of satisfaction building something that works and can be used ...
can be seen on Field Day...
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