Re: QRP balun query


W3BNO
 

Lloyd I build  baluns into all of my coax feeb lines. I also have a 1:1 current balun which is referred to as an isolator because it isolates the coax shield from the counter poise. This makes tuning verticals that use elevated radials much easier to tune. I make my 1:1 current baluns by wrapping 12 turns of rg174 through a FT140-43 core. I use the larger core to keep the bend radius of the coax at a reasonable level to minimize distortion of the foam dielectric. I believe the cores cost approximately $2.50 each from Diz at parts and kits. That's double the cost of the 114 cores but I look at the increased cost as insurance. Also don't try and make tight turns that conform to the core., just a loose wrap and use an abundance of wire ties to hold it all together. Before I started using these, it was all but impossible to tune my buddy stick, and some of my rigs that are sensitive to RF are now happy and work as they should. W3BNO


On Jan 2, 2021, at 8:57 AM, n0sa@... wrote:

10 to 12 turns of RG174 on a FT-114-43 toroid core should do the job.
Larry
n0sa

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