Absolutely not true!!! If you take the aluminum required for monobanders, 3 or 4 or 5 elements each, for three bands 10, 15, and 20M, and make one log out of it, you get the WARC bands, all of every
Hi, I have and the stacking distance depends upon the characteristis of the LPDA. High taper factor (above .92 or so) and high spacing factor (above 0.05 or so) require larger spacing due to the high
Hi Jim, That stacking method has been used for VHF antennas and only works in the "free space" that VHF and UHF antennas see many wavelengths above ground. At HF, the ground reflection is important a
In getting back to the basics, I submit that at heights over 4 to 6 wavelengths above ground, the antenna is in "free space" and that's why the "nulls"are filled in. Also, at these heights, in free s
Was this by any chance in an April issue?? :>) This "deep thread" about modeling ant has been a great help in showing me just how much about "tech details" I still have to learn - thanks to all. My q
Just wondering...were you able to measure performance before and after painting? --Original Message-- From: Stuart Browne [SMTP:satcom@lava.net] Sent: Monday, February 04, 2002 6:34 PM To: wd3q@erols
I bought this for a crank up tower but it will not fit! This is the biggest of the amateur rotators. You can see the specs at: http://www.prosistel.net/home-e/default_net.html Look at the menu on the
" The discomfort I have with that idea is I just spent a couple of paychecks on Phillystran, and I hate to think I'd negate all that expensive electrical isolation by hanging a bunch of wires from th
I can't answer this question, but it brings up a question I had about upgrading two of these antennas myself. I am contemplating doing the same since they have become intermittent. My question is wil
Reinventing is what it's about! That old design was produced to be cheap, that's why you had to rebuild yours. I'm sure the electrical design is not optimized either. My question is simply to those f
A little additional clarification. I haven't modeled this yet but are the inductors deliberately lower Q, read "higher loss" to add some "R" to perhaps 1) improve SWR bandwidth and F/B and/or 2) brin
Not really. I bought a KLM 80M-3, a 3 E 75M yagi in 1984 and had it up 9 years. I modified it by adding Phillystran to side guy the elements and the boom. I did not change any of the materials suppli
Hi Jay! I like that system! I have constructed and have had up since 1992 a pair of stacked logs that cover 13.5 to 30 MHz, at 55 and 110 ft. Each log is 18 E on a 62' boom, top rotated with a large
Thank you folks! Interesting comments. A good summary of concerns regarding my original question can be found at: http://www.qth.com/ka9fox/pier_pin_vs_embedded_base.txt This was referred to me by an
Hi folks, I've seen quite a few installations being planned here starting out with the botton section of tower sunk in concrete. What I'm curious about is why a pier pin isn't used? On all my towers
I had the same "harmonic" noise with my TIC ring rotors, including BC station harmonics that came and went while the ring is turned. In my case the source was the contact between the drive gear and t