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Messages - W7LPN

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1
Equipment / Re: T2FD Antenna
« on: May 31, 2010, 0544 UTC »
Actually I'm gonna rip them a new one! I've been hitting DX on 10m, & 20m, lots of 600-1800 mile chat on 40m, and my nightly net check-ins on 75m west coast. This IS A QUIET ANTENNA, and a Good performer, matching at least equal to all barefoot incoming signals and equal to one pushing 600 watts.

2
Equipment / Re: T2FD Antenna
« on: May 30, 2010, 0450 UTC »
I'm actually going to collect more information first so they can't claim 40m is the only band my antenna will Tx on.  :P

3
Equipment / Re: T2FD Antenna
« on: May 29, 2010, 0350 UTC »
Those guys can bite me! I received it today, put it up in a hurry. 40m from Boise to Tacoma to Joe with a 60ft vertical with 600watts, I'm barefoot with 100 watts , we both are 5/9!!!

4
Equipment / Re: Super Antenna
« on: May 27, 2010, 2108 UTC »
With ant compact antenna system the counterpoise, feed point impedance, and grounding become even more critical. It will still work well and be a lot of fun! Good luck & have fun.

5
Equipment / Re: Pneumatic Antenna Launcher
« on: May 27, 2010, 2102 UTC »
I use a wrist rocket sling-shot, 1-2oz fishing weight, a spinning real mounted to the rig. With 10lb or lighter line you can shoot it up quite high and pull a larger twine over the tree. I do this every summer and It's cheap, especially if you already have a wrist rocket and an old broken fishing pole, to take the real from.  8)

6
Equipment / Re: Electrostatic discharge protection tips?
« on: May 27, 2010, 2055 UTC »
http://www.w8ji.com/lightning.htm     ;D  check this out....good reading.

7
Equipment / Re: T2FD Antenna
« on: May 23, 2010, 0501 UTC »
A fellow ham friend is an ex-military, then commercial RF engineer for 40-50 years, and I trust his judgment implicitly. He doesn't have to prove a thing, has been on the local ham clubs board of directors, or a welcome guest at tech meetings for decades. working at a career for 8+ hours a day for nearly 50 years trumps a test you can take 100 times, on line, to practice the right answers, while comprehending nothing, every time in my book.

8
Equipment / Re: T2FD Antenna
« on: May 22, 2010, 1630 UTC »
I agree completely. Some folks quote technical mumbo-jumbo and have never used the antenna to which they are criticizing. Buck Has one up & has used it for years. The only reason for posting quotes is to sift through the garbage & get to the facts, which I believe I've done. That's why I went ahead and purchased this antenna. I'll know for myself within a couple weeks whether it will operate as advetised here at my QTH. I understand good earth, poor earth, salt water, grounding & reflection, so I'm no ostrich. I will understand some or most of the why's or why not's. 

9
Equipment / Re: T2FD Antenna
« on: May 21, 2010, 1652 UTC »
I bought it! Thanks guys. I saw no reason so many positive reviews(unsolicited w/o monetary gain) would exaggerate or lie about favorable antenna performance. I think Buck called it right. http://www.buxcomm.com/catalog/index.php?main_page=product_info&cPath=45&products_id=2184&zenid=qj0ragan0h62c260r6lvhbbsf3

10
Equipment / Re: T2FD Antenna- Please reply
« on: May 20, 2010, 1711 UTC »
I'm searching for the truth. Please read.  :)

 W8JI
Ham Member
        
Join Date: Oct 2003
Posts: 2,853
Send a message via Yahoo to W8JI
Default
Any one additional comment you can pass back to "tube shortwave" about this:

"If they had a shred of knowledge in this department, they would know that a balancing resistor on the OPPOSITE side of a folded dipole does not absorb "half the transmitter power" at all. "

That wasn't the statement at all. He isn't even honest enough to quote someone accurately.

The statement I made (it is in black and white here on the Zed, so there is no debating he misquoted) is the resistor sometimes dissipates less than half of the power applied to the T2FD antenna, and on other bands it dissipates much more than half the applied power. Nothing worse than a critic who fabricates the very statements he is openly critical of.

He goes on to say:
"If that were true, that resistor would blow up every time I run 1500 watts on CW. In fact, at most, the resistor will absorb 1/4 of the transmitter power if the antenna is that far out of resonance on my chosen operating frequency. The other 3/4 is radiated with a very small amount coming back (<10%). Most of the time, the balancing resistor isn't doing very much."

That's clearly wrong, as any analysis or measurement has shown. What "tube shortwave" is unaware of is the owner of Amp Supply found that antenna design in some publication and decided to build it commercially. I believe he eventually cooked up a deal with B&W to buy the "design" of that, and a terminated V, antenna. The original matching transformers were the filament chokes from amplifiers, wound at Prime Instruments.

I actually directly measured the dissipation in the resistor and it was pretty high overall.

There is considerable mutual coupling between the dipole half with the resistor, and the dipole half with the feedline. Anyone who knows anything about antennas understands mutual coupling of two very long wires (90 feet or so long) spaced a few inches apart is extremely high, plus the ends of the wires are directly connected. The resistor is, for nearly all practical purposes, directly connected across the feedline.

The power division depends largely upon the unterminated impedance at the feedpoint. On bands where the antenna is a conventional half-wave or 3/4 wave dipole length, that impedance is low and the resistor has limited effect on the system. On bands where the feedpoint would have a high unterminated impedance, the resistor soaks up most of the energy.

This is why the SWR stabilizes. What would be a terrible SWR on some bands is reduced by diverting energy into the resistor on those bands.

When testing the antenna as a consultant doing work at Amp Supply, I built an antenna at home and ran the "resistor" side through ladder line to a dummy load. I had an RF current meter in series with the load, and measured load current. I still have the huge resistor I used here, I use it as a dummy load for testing high impedance balanced systems. The measured result was basically as LB Cebik and many others have analyzed and published.

If you search the web you will find many articles telling exactly what the T2FD antenna is, and what it is not.

11
Equipment / Re: T2FD Antenna
« on: May 19, 2010, 1929 UTC »
Thanks again. I am not an RF engineer. I know a few of them & they make more sense than any of these "Hambones" you speak of. When he was criticizing the effects of the non-terminating resistor, it sounded like puffed up BS. Sooner or later you can recognize the truth and the level heads in a discussion. Tahnks , & 73. 

12
Equipment / Re: T2FD Antenna
« on: May 19, 2010, 0501 UTC »
Thank you for an honest real-time evaluation. I don't really care about whether anyone believes these antennas(T2FD & Windom) have been conspired against. I'm sure if I was the manufacturer and couldn't get a fair deal I would feel very different about it. If you occasionally get on QRZ forum look up antennas, limited space W7LPN thread. The so called experts have been bashing the t2fd for a few days. I'm relatively sure these "Experts" don't, nor ever have, owned a commercially manufactured T2FD. The truth as you have stated it needs to be known.

13
Equipment / Re: T2FD Antenna
« on: May 17, 2010, 1737 UTC »
"W7LPN thanks for your Emails:
Trust me, I've read them all.... Even ole Marty Jue..(XXX) notes of distain:...

The problem now is, all the advertisers who pay big buck$ with XXX, & XX mags to advertise their Antenna tuners have now threatened the ARRL/QST, and CQ to redraw or reduce their advertising if they continue to publish articles about T2FD, and WINDOM (tunerless) antennas.  ANY Antenna that does not use an antenna tuner that could be written about in these pubs are bad news for the leading Amateur Publications.  Cebik is now SK, but back when he wrote that piece, he was writing books for QST/ARRL.

For eighteen years, I was the digital editor of XX magazine, never missed a month writing my column.. sometimes several...  Then when I wrote an article about the T2FD, they refused to print it... then I wrote an article about the Windom.... suddenly I had some sort of writers disease... they would not print it either.

I was furious, as I had put a lot of time and effort into those articles (column). 

I gave them my "notice" and immediately stopped writing for them.  They got P/O'd and then one of the employees of XX (nameless), called and informed me WHY they would not print my articles about the antennas that did not need an Antenna Tuner....

Seems two of their biggest advertisers threatened to pull all their advertising dollars if they ever gave credence to any article(s) that took away antenna tuner sales.

It's a sad day when politics enters our hobby, and begin to dictate editorial policy… and the rank-n-file HAM suffers because of the all-mighty dollar.

Up until 1995, all the handbooks, HAM magazines, and league publications (Antenna Books) had articles about T2FD, Windoms and specific antennas that did not require an antenna tuner. 

SUDDENLY, all the Antenna handbooks, Annual Amateur Radio Handbooks.. and publications sold by the XXXX, XXX, or XX, took a noticeable difference in their hobby antenna related content and antenna information:!

ALL, I mean ALL reference to the T2FD, the Windom, and tunerLESS antennas was noticeably missing from these rags!
Here be side me, in my BOOK CASE are the last 4 years of ARRL Annual Handbooks.  Not a word about these antennas.

Add to that, I have the ARRL Classic Wire type Antenna Handbook; first Edition Copyright 1999 through 2009.
Here is a book that should be bulging with T2FD, Windom and other WIRE type antennas (that don’t need antenna tuners), alas… NOTHING!
I tried to make a big noise, but I was laughed at because I related this to some of the "powers-that-be" at the league, and XX.... they poo poo'd it and denied it no less.

I rest my case.

Now you understand why I don't advertise in any of these “Hobby Rags.”

Every chance they get, they'll have some of their cronies put something on an antanna review page in print, trying to discredit me.  I'm still here, and most of them are out to pasture.

AND now’ you know "The rest of the story !"

Have a great weekend."

Anonymous, but not too hard to tell who it is.

 


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