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Author Topic: Design for a 20/30m GP. Any suggestions??  (Read 1329 times)

Offline GM0LVI

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Design for a 20/30m GP. Any suggestions??
« on: September 30, 2016, 20:13:09 UTC »
Does anyone have a design for a coil loaded 20/30m GP antenna, preferably using a full 1/4 wave radiator on 20m?
This year in SV8 I found 20m very poor and often resorted to using my fishing pole 20m GP on 30m - it radiated but with a decent loading coil to bring it to resonance on 30m it would put out and receive much better.

Thanks for any suggestions!
Dave
Dave

DF5WW

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Re: Design for a 20/30m GP. Any suggestions??
« Reply #1 on: October 09, 2016, 05:02:21 UTC »
Hi Dave,

if you using a fishing pole why you not use a 7 m radiator and 3 elevated 7m radials ?? You can feed it with ladderline to a tuner which can handle this kind of feeders. Antenna doing a fine job between 7 and 50 MHz (if verticals for 6 are allowed, here in DL only horizontal  :(  ) .... Have tried this kind of antenna on my last QTH and i have had great results also in DXing.

 ;) ;)

Offline GM0LVI

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Re: Design for a 20/30m GP. Any suggestions??
« Reply #2 on: October 09, 2016, 07:58:57 UTC »
Thanks Juergen! I'll do a scale drawing to see how well one would fit on the back of our motor home, but the length of the radials might be a problem as we have limited space on campsites, my 12/17/20 GP radials just fit.
Off to our west coast tomorrow for a week of QRP/P :-)
Dave

Offline GM0LVI

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Re: Design for a 20/30m GP. Any suggestions??
« Reply #3 on: October 09, 2016, 18:09:11 UTC »
I've found a design for a 80-15m vertical. Looks quite good.

http://www.perite.com/vk7jj/squidpoles.html
Dave

Offline sm5mek

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Re: Design for a 20/30m GP. Any suggestions??
« Reply #4 on: December 16, 2016, 13:38:54 UTC »
Best regards, 72 de SM5MEK, Jenny.

Offline GM0LVI

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Re: Design for a 20/30m GP. Any suggestions??
« Reply #5 on: December 16, 2016, 19:21:07 UTC »
Many thanks Jenny, I knew you had some good designs for multi-band verticals!
I've solved my problem and have just ordered on Tuesday this week a Spiderbeams 12m fishing pole so will simply run a 30m GP radiator down from the top and a 20m radiator offset by a few cm parallel to it. The radials will be attached about 4.5m up from the base and slope down at about 45 degrees. It's not a very light and portable antenna like yours, but will be great when go go the island of Barra in April. I've found a cottage with the ideal location for playing radio!
Have a great Christmas and I hope to work you again sometime in 2017.

73/72 Dave

Dave