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

[Dick Bingham]

Greetings everyone

Has anyone here messed-with a tuned loop on 600-meters. At the QRP levels
provided by the Ultimate-3, high arc-over voltages  would, I suspect, not
present significant problems. Correct me if I am wrong so I do not
re-invent a failed project !

73 - Dick/w7wkr XSH/26

On Wednesday, January 22, 2014, John Langridge <jlangridge at sbcglobal.net>
wrote:

> Ed,
>
> Not a crazy idea at all.  I've seen a number of 160m mobiles with tall
> coils wound  on 10 inch forms plus a helical whip.. I guess they work.
> I've used a helically wound fishing pole on 80m for fox hunting with my
> local club and it seems ok.
>
> I may work on a helical system after getting some baseline data tonight
> with the straight whip (really 1" aluminium "antenna" pipe).  This was born
> out of a passing comment with XKA yesterday on a similar topic.  I would be
> interested in seeing how quickly the system improves with some top loading.
>
> Congrats the XXM Ken for hearing it twice on ground wave at the ragged
> edge of WSPR2 capabilities.  This might be a job for WSPR15.
>
>
> SO far, the clear winner remains the 20m inverted vee with 25 feet of
> ladder line fed as a marconi.  Don't expect it to be unseated by the 102"
> antenna tonight but we will see.
>
> 73,
>
> john XIQ
>
>
>
> ________________________________
>  From: Edward R Cole <kl7uw at acsalaska.net <javascript:;>>
> To: John Langridge <jlangridge at sbcglobal.net <javascript:;>>; "
> 600mrg at w7ekb.com <javascript:;>" <600mrg at w7ekb.com <javascript:;>>
> Sent: Wednesday, January 22, 2014 4:18 PM
> Subject: Re: [600MRG] WG2XIQ U3 Experiment - loading a 102" pipe on 630m
>
>
> 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 <javascript:;>
> > 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
> http://www.kl7uw.com
>     "Kits made by KL7UW"
> Dubus Mag business:
>     dubususa at gmail.com <javascript:;>
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-- 
Dick Bingham - W7WKR
Stehekin, WA    CN98pi

OR

East Wenatchee, WA  CN97uj