The article I originally referenced is in the May 1975 "HAM RADIO" magazine not QST. I did not know there were similar articles in both mags the same month 73, Bob, W5AH --Original Message-- From: ow
Dan, I went back to the Ft Wayne site and found the HR article. There is also a QST article on the site. From reading the posts, I think there may have been an access problem because I didnt get ever
John, You did not mention it but Im guessing your SWr was around 2:1. I think you will find that a center fed half wave vertical will have a feedpoint Z on the order of 100 Ohms when the feedpoint is
MIke, Since you did not specify narrow or broad band, Ill take the easy route and say make a choke balun out of a length of 75 ohm coax that is 1/4 wavelength long at the desired frequency. Connect t
Pete, Find a copy of May, 1975 Ham Radio magazine and check out the article titled "How to Design Shunt-feed Systems for Grounded Vertical Radiators" by John True, W4OQ. I do not think there has ever
Perhaps I've missed something, but these disclaimers seem totally absurd Bob, W5AH --Original Message-- It's intended to show others (those on the list to which the posting is made) that what is bein
Hi Ted, My RG Cable Guide is so old it does not list RG8X. However, for RG8 and 8A it says to use RG213. If weight is a concern, why not use a half wavelength of ladder line from the antenna feed poi
The only "engineering" antenna Im aware of is called an isotropic radiator. Build one and you get a free trip to stockholm. 73, Bob, W5AH I am interested in looking at the effectiveness of modeling a
Hi David, Check out the "ARRL Antenna Compendium" Volume 2 page 10 for a good two vertical array project. It will work well with multi-band verticals too. 73, Bob, W5AH All the 4sqr talk has inspired
Hi Arliss, Use an Omega match. Attach the gamma rod 30 feet above ground. It should be on a corner of the tower and spaced about 6" from the tower leg. The series cap will be very close to 875 pf and
Another good replacement for the original balun is a 4-wire balun wound on stacked F240 cores...stack two cores for each of the bifilar windings and put them in any enclosure you choose. and is not w
Jim, According to information I received last week from our local Ham store, KLM is out of business for all except spare parts. When the existing spare parts are gone so is KLM. You might give Texas
Hi Jim, I replaced mine with a TH-7. I wish I had purchased a th7 in the first place. As for performance, gain and SWR... all the large tribanders are pretty much alike. Only the manufacturers claims
-- Hi Paul, An 80 meter dipole will work quite well on 30 meters, all you need is a tuner. No traps needed. However, if you do not have a tuner... Cut your 30 meter dipole to length per the usual for
Hi George, Try pouring Hydrogen Peroxide over the stuck joints and let it seep into the seam. It might take a while but the aluminum sections will come apart it they are not crimped together. You sho
This is a multi-part message in MIME format. --=_NextPart_000_0019_01BEEAED.2D4E2F80 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thank you --Original Me
Check out the site of the week on dxer.org for pix of the newest big gun in Texas. 73, Bob, W5AH -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Admin
-- Tom, A 1:1 choke balun is called for and a very short length of coax to the tuner. 73, Bob, W5AH -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com A
-- Brian, For your own safety, the safety of your antenna and the safety of surrounding structures, I would suggest you stack Rohn 25 or 45. Do not try to build tower sections yourself. 73, Bob, W5AH
Randy, Find an old inner tube and slice it open. Wrap the mast with one turn and retighten th u-bolts/ clamps around it. That should take care of the problem. I have a Ham IV currently turning a TH7