Hello I am looking for some brain power from anyone who has built loop yagi's. I am getting my information from The ARRL Antenna book 20th edition. The book says follow exactly, however. It calls for alluminum elements 0.0325 thick, I have copper 0.025 thick. It calls for 3/4" alluminum boom I have 3/4 copper and some 1/2" stainless steel channel. The feed to the driven element is UT-14, I have a short piece with a SMA already attached, will connecting the SMA to a SMA-N adapter be acceptable? I have seen the pretty pictures of Directive Systems antennas http://www.directivesystems.com/loopyagi.htm Same idea only different parts. Are these things pretty "forgiving" or are the components critical? Also comparing the loop to a quagi the loop widths are 1/4" wide and the quagi used #18 wire, why? My intent is satellites and/or terrestial. Thanks for the bandwidth. 73 Bob W7LRD CN87 AMSAT 28498
-- "if this were easy, everyone would be doing it"
I've have two directive systems loop yagis. The bandwidths are only slightly wider than yagis with straight elements so dimenional tolerances will be about the same. They are similar to HF quads. Each element behaves like 2 stacked dipoles with bent ends. The only unforgiving antena is a helix.
73,
John KD6OZH
----- Original Message ----- From: w7lrd@comcast.net To: "NW VHF" PNWVHFS@googlegroups.com; "AMSAT-BB" AMSAT-BB@amsat.org Sent: Thursday, January 29, 2009 18:25 UTC Subject: [amsat-bb] homebrew Loop yagi
Hello I am looking for some brain power from anyone who has built loop yagi's. I am getting my information from The ARRL Antenna book 20th edition. The book says follow exactly, however. It calls for alluminum elements 0.0325 thick, I have copper 0.025 thick. It calls for 3/4" alluminum boom I have 3/4 copper and some 1/2" stainless steel channel. The feed to the driven element is UT-14, I have a short piece with a SMA already attached, will connecting the SMA to a SMA-N adapter be acceptable? I have seen the pretty pictures of Directive Systems antennas http://www.directivesystems.com/loopyagi.htm Same idea only different parts. Are these things pretty "forgiving" or are the components critical? Also comparing the loop to a quagi the loop widths are 1/4" wide and the quagi used #18 wire, why? My intent is satellites and/or terrestial. Thanks for the bandwidth. 73 Bob W7LRD CN87 AMSAT 28498
-- "if this were easy, everyone would be doing it" _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
There is an article on the North Texas Microwave Society website about building a 1296 MHz loop yagi.
Go to
Then look at the list of links on the left hand side of the page. Click on "Tech Library". Then choose "The NTMS 1296 Loop Yagi Project - Al Ward - W5LUA (pdf) 169k".
The link just below that one has some technical measurements.
Glen, K9STH
Website: http://k9sth.com
--- On Thu, 1/29/09, w7lrd@comcast.net w7lrd@comcast.net wrote:
I am looking for some brain power from anyone who has built loop yagi's. I am getting my information from The ARRL Antenna book 20th edition. The book says follow exactly, however. It calls for alluminum elements 0.0325 thick, I have copper 0.025 thick. It calls for 3/4" alluminum boom I have 3/4 copper and some 1/2" stainless steel channel. The feed to the driven element is UT-14, I have a short piece with a SMA already attached, will connecting the SMA to a SMA-N adapter be acceptable? I have seen the pretty pictures of Directive Systems antennas
http://www.directivesystems.com/loopyagi.htm
Same idea only different parts. Are these things pretty "forgiving" or are the components critical? Also comparing the loop to a quagi the loop widths are 1/4" wide and the quagi used #18 wire, why? My intent is satellites and/or terrestial. Thanks for the bandwidth.
Don't forget the designs in the RSGB Radio Communications Handbook for 23 and 13 cms.
Glen Zook wrote:
There is an article on the North Texas Microwave Society website about building a 1296 MHz loop yagi.
Go to
participants (4)
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Glen Zook -
John B. Stephensen -
Nigel Gunn G8IFF/W8IFF -
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