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G3TXQ wrote:

ei9ju wrote:

Steve, I'm having trouble separating the coax feeder from the 6m quad driven element.
I visited your site to see what info there was on air wound chokes but your page only deals up to 30mhz. Is an air-wound choke feasible at 50mhz?

Sure - it's feasible; it's just that air-cored chokes are so High-Q that you only have to change the winding diameter a small amount, or add an extra turn, and the thing no longer has high impedance where you want it. In fact, the only reason I included any on my chart was to demonstrate how narrow band they are!

All that said, 4 turns of Rg213-size on a 4" diameter should be about right for 6m.

73,
Steve G3TXQ

Author:	ei9ju [ Tue Mar 27, 2012 7:07 pm ]
Post subject:	RF Choke
Steve, I'm having trouble separating the coax feeder from the 6m quad driven element. I visited your site to see what info there was on air wound chokes but your page only deals up to 30mhz. Is an air-wound choke feasible at 50mhz?

Author:	G3TXQ [ Tue Mar 27, 2012 8:56 pm ]
Post subject:	Re: RF Choke
ei9ju wrote: Steve, I'm having trouble separating the coax feeder from the 6m quad driven element. I visited your site to see what info there was on air wound chokes but your page only deals up to 30mhz. Is an air-wound choke feasible at 50mhz? Sure - it's feasible; it's just that air-cored chokes are so High-Q that you only have to change the winding diameter a small amount, or add an extra turn, and the thing no longer has high impedance where you want it. In fact, the only reason I included any on my chart was to demonstrate how narrow band they are! All that said, 4 turns of Rg213-size on a 4" diameter should be about right for 6m. 73, Steve G3TXQ

Author:	ei9ju [ Tue Mar 27, 2012 9:18 pm ]
Post subject:	Re: RF Choke
G3TXQ wrote: ei9ju wrote: Steve, I'm having trouble separating the coax feeder from the 6m quad driven element. I visited your site to see what info there was on air wound chokes but your page only deals up to 30mhz. Is an air-wound choke feasible at 50mhz? Sure - it's feasible; it's just that air-cored chokes are so High-Q that you only have to change the winding diameter a small amount, or add an extra turn, and the thing no longer has high impedance where you want it. In fact, the only reason I included any on my chart was to demonstrate how narrow band they are! All that said, 4 turns of Rg213-size on a 4" diameter should be about right for 6m. 73, Steve G3TXQ Cheers Steve I'll try that tomorrow night, it'll tide me over until I get a load of clip-on ferrite cores.

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