[600MRG] WG2XIQ U3 Experiment - loading a 102" pipe on 630m

[Edward R Cole]

At 12:30 PM 1/22/2014, John Langridge wrote:
>Ladies and Gentlemen, for your listening pleasure, I will be running 
>a 102" pipe fed against an existing radial system from my normal 
>QTH.  The coil, as expected, was a huge challenge and needed a 
>significant amount of additional series inductance to resonate.  The 
>match is good for the moment and I am expecting no more than 5 mW 
>ERP in WSPR2, 474.2 dial.
>
>I fully expect this antenna to have some problem over night at some 
>point but since its running from the home station, there may be 
>something I can do.  Hopefully it will run all night and into 
>tomorrow or until it catches fire, which is a real possibility.
>
>
>73 and thanks for listening and submitting reports.
>
>John WG2XIQ/KB5NJD
>_______________________________________________
>600MRG mailing list
>600MRG at w7ekb.com
>http://w7ekb.com/mailman/listinfo/600mrg_w7ekb.com

John,

102 inches = 8 -1/2 feet!  In meters = 2.6.  So the vertical is 
2.6/157.5 = 1.7% of a full 1/4 wave.  Wow!

I wonder at this length whether it might make sense to wind a helical 
antenna to distribute the current more equally?  I guess one could 
calculate the diameter and number turns to be resonant and tap off a 
the ground end to match 50-ohms.

Suppose one wound on a 12-inch form by 10-foot; what could you 
use?  I guess what I am thinking about is a portable antenna/mobile 
antenna.  Ground plane is problematic.

Maybe a crazy idea?

73, Ed - KL7UW


73, Ed - KL7UW
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