Re: Topband: Inverted-L question

Hi Steve, 5300 pF is way large. It indicates *something *else is going on. "Something" needs to be determined. One thing for sure, after nearly a decade of correspondence with this as a frequent subject, there is no one single "silver bullet" to fix this in all cases. It is complicated and with

Re: Topband: Inverted-L question

Remember, Steve, for a given frequency more capacitance equals less capacitive reactance [Xc = 1/(2*pi*f*c)]. At 1825 KHz, 5300 pf is only 16.5 ohms reactance. That means you are only offsetting a small amount of inductive reactance. Where you should be more concerned is when the series

Re: Topband: Inverted L Question

FWIW, for 160 I used my old 97-foot Rohn 25 tower, with 2 tribanders and a 40M 2-el on it, shunt fed at about 50 feet.  I had a pair of 300 uf variable caps at the bottom, one in series with the feed and the other in parallel.  It proved to be easy to tune to low SWR once I discovered that the

Re: Topband: Inverted L Question

On 12/21/2023 12:54 PM, Paul Dulaff via Topband wrote: Ran a basic EZNEC model with no tower present for your 80 ft X 45 ft inverted L at 1.825 Mhz. The base impedance for this is 28.5 - j 130 ohms.  The get rid of the reactance I extended the top wire an additional 20 ft so 80 X 65 ft and

Topband: Inverted L Question

Steve Ran a basic EZNEC model with no tower present for your 80 ft X 45 ft inverted L at 1.825 Mhz. The base impedance for this is 28.5 - j 130 ohms.  The get rid of the reactance I extended the top wire an additional 20 ft so 80 X 65 ft and base impedance is 37.2 + j0. The tower is

Topband: Inverted-L Question

Steve, For comparison my inverted-L is similar to yours with a 94 ft vertical section and 43 ft horizontal (ish). It is on a tall tree, not a tower. Like you, I use an L-network to match it and get a feed impedance on 1826.5 KHz of 50+j0. I have a 1600pF capacitor in parallel but no inductor as I

Re: Topband: Inverted-L question

Without getting into the measurements - I think you need to detune the tower if that is going to work at all. Probably put a trap in the bottom 20 feet. Tree N6TR On Thu, Dec 21, 2023 at 6:27 AM Noel Lopez via Topband < topband@contesting.com> wrote: > Here is my 2 cents worth. First of all,

Re: Topband: Inverted-L question

Here is my 2 cents worth.  First of all, I am not an antenna expert nor do I know how to use antenna modeling software.These are my thoughts based on my experience and what I remember reading.  My low band system is an inverted L under a SteppIr yagi that can be retracted.  This avoids the

Topband: Inverted-L question

I have an Inverted-L question that hopefully someone can answer for me. I installed the 160m wire to the 80 ft level on a 100 ft Rohn 45 tower with top mounted yagis. The horizontal (sort of) portion is approx 45ft long. The wire starts at 80 ft down approx 5 ft from tower and when it gets to

Topband: Inverted L - I surrender

I'm going to take the antenna back down tomorrow, test to be sure that there's nothing freaky like a break in the wire, and then take it and my K9AY loop in for the season.  Mowing starts in another few weeks and I'd just as soon roll up my radials for another day.  In the meantime I'll rewind

Re: Topband: Inverted L with elevated radials for topband

When it comes to elevated radials, the amount of guys who have strong opinions on the subject are many - and unfortunately the amount of objective data behind those strong opinions is generally not existent.  On the other hand, the N6LF work is one of the few well documented objective works

Re: Topband: Inverted L with elevated radials for topband

I haven’t experimented on top band but I have tried elevated radials on 80M ¼ verticals. I had one in Houston Texas that worked wonderfully – elevated 8 radials at about 10 ft. Ground conductivity in Houston was about as good as anywhere in the US. I tried doing the same thing at 2 different

Re: Topband: Inverted L with elevated radials for topband

I second this. Wes  N7WS On 3/5/2020 4:43 PM, Grant Saviers wrote: Read all of what Rudy N6LF says, and you will be an expert. Grant KZ1W _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Inverted L with elevated radials for topband

ank W3LPL - Original Message - From: "Bill Stewart" To: "Gabriel - EA6VQ" Cc: "topband" Sent: Thursday, March 5, 2020 8:13:08 PM Subject: Re: Topband: Inverted L with elevated radials for topband Hi Gabriel, These comments will be of little help as f

Re: Topband: Inverted L with elevated radials for topband

On 3/5/2020 11:26 AM, Mike Waters wrote: Many hams --including myself-- have had very good results using only a few elevated radials. Yes. One of the key factors is the height of the radials. N6BT, who has done a LOT of work with elevated radials on topband, told me that 18 ft is a minimum

Re: Topband: Inverted L with elevated radials for topband

comments in line On 3/5/2020 10:02, Gabriel - EA6VQ via Topband wrote: I have some doubts about installing and inverted L with elevated radials for 160m. I have been searching in Google and find some contradictory information, so I would appreciate very much if you can help me with your own

Re: Topband: Inverted L with elevated radials for topband

My experience too, Bill! The very first time I tried my inverted-L with the two elevated radials etc., I broke a number of pile-ups in a contest with 100 watts! At that time, I did not have an amplifier that covered 160m. After that, for awhile I made a game out of turning down the power output

Re: Topband: Inverted L with elevated radials for topband

al Rig Expert. Happy experimenting! 73 Mark, PA5MW -Original Message- From: Topband On Behalf Of Gabriel - EA6VQ via Topband Sent: Thursday, March 05, 2020 19:02 PM To: topband@contesting.com Subject: Topband: Inverted L with elevated radials for topband I have some doubts

Re: Topband: Inverted L with elevated radials for topband

S/NC - Original Message - From: "topband" To: "topband" Sent: Thursday, March 5, 2020 1:02:07 PM Subject: Topband: Inverted L with elevated radials for topband I have some doubts about installing and inverted L with elevated radials for 160m. I have been searching

Re: Topband: Inverted L with elevated radials for topband

Many hams --including myself-- have had very good results using only a few elevated radials. This question contains an answer with a NEC 4.2 plot comparing the efficiency of earth vs. elevated radials:

Topband: Inverted L with elevated radials for topband

I have some doubts about installing and inverted L with elevated radials for 160m. I have been searching in Google and find some contradictory information, so I would appreciate very much if you can help me with your own experience. The antenna would be supported by a 16 m (52.5 ft) high

Re: Topband: Inverted L and the High Angle Field

Thanks for clarifying that. I didn't mention that because I thought it was so obvious. Also, the 5th edition of *Low Band DXing* is in favor of the T over the inverted-L. 73, Mike W0BTU On Sat, Feb 29, 2020, 2:33 PM Jim Brown wrote: > ... depends on the relative lengths of the horizontal and

Topband: Inverted L and the High Angle Field

On 2/29/2020 9:56 AM, Guy Olinger K2AV wrote: Have to disagree on the no-use-for the horizontal leg. It fills in the doughnut hole in the high angle radiation, which in contests is very good for keeping others from planting on your run frequency. Also there are high angle path opportunities

Re: Topband: inverted-L

: Topband [mailto:topband-boun...@contesting.com] On Behalf Of N4ZR Sent: 04 September 2019 01:29 To: topband reflector Subject: Topband: inverted-L Thanks to everyone who responded to my message - lots of good ideas. I think my favorite was the one about tapping a shunt coil from both ends, alternately

Re: Topband: Inverted L redux

-content/k3lcmaxgainradials.pdf 73 Frank W3LPL - Original Message - From: "N4ZR" To: "topband reflector" Sent: Monday, September 2, 2019 7:08:16 PM Subject: Topband: Inverted L redux More as an experiment and a thought-provoker than anything else, I've start

Re: Topband: Inverted L redux

Add more short (50 - 60 foot) radials, IMHO. Some 45 years ago I worked as a wireless operator in fixed service on 60m band (my call has been 4NC24L) and we used L antennas. At my surprise, ground was just 3' of galvanized pipe knocked into the ground. At company's electrician workshop I got heap

Re: Topband: Inverted L redux

Four 50-60 footers. See: https://www.antennasbyn6lf.com/files/antenna_ground_system_experiment_4.pdf for my rational. Wes  N7WS On 9/2/2019 12:08 PM, N4ZR wrote: More as an experiment and a thought-provoker than anything else, I've started adding 50-60-foot, on-the-ground radials to my

Topband: Inverted L redux

Clive GM3POI -Original Message- From: Topband [ <mailto:topband-boun...@contesting.com> mailto:topband-boun...@contesting.com] On Behalf Of N4ZR Sent: 02 September 2019 19:08 To: topband reflector Subject: Topband: Inverted L redux More as an experiment and a thought-provoke

Re: Topband: Inverted L redux

On 9/2/2019 12:08 PM, N4ZR wrote: More as an experiment and a thought-provoker than anything else, I've started adding 50-60-foot, on-the-ground radials to my 135-foot inverted L.  In the latest incarnation I'm up to 4 radials.  On my ancient MFJ-259B the lowest SWR is 1.3:1 at 1825 KHz,

Re: Topband: Inverted L redux

point. 73, Bob K3UL -Original Message- From: Topband On Behalf Of N4ZR Sent: Monday, September 2, 2019 3:08 PM To: topband reflector Subject: Topband: Inverted L redux More as an experiment and a thought-provoker than anything else, I've started adding 50-60-foot, on-the-ground radials

Re: Topband: inverted l

If you have a properly constructed typical inverted L, i.e. 50 or 60 foot vertical and similar length horizontal, AND a good ground system serving as the other half of the antenna, your feedpoint Z will be 10 to 20 ohms. The reason you need a matching network is that most coax (this assumes you

Re: Topband: inverted l

Hi Doug Ignore those splitting hairs. :) Yes, and inverted L will represent a load that should work for your radio without any additional tuners (should). I run an inverted L right up the side of an 80 ft pine tree and then I have 4 elevated radials. 2 of those radials parallel a fence that

Re: Topband: inverted l

Matching network does not resonate the antenna Guys Will a invereted L a quarter wave length resonate at a given frequency without a matching network? Doug wd8z Sent from Mail for Windows 10 _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: inverted l

Anything will resonate at some frequency.  The question should be will it be a good match at the desired frequency. Wes  N7WS On 9/1/2019 4:02 PM, doug dietz wrote: Guys Will a invereted L a quarter wave length resonate at a given frequency without a matching network? Doug wd8z Sent from

Topband: inverted l

Guys Will a invereted L a quarter wave length resonate at a given frequency without a matching network? Doug wd8z Sent from Mail for Windows 10 _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: Inverted L in contact with leaves

Hi Pete. My inverted L over K2AV FCP was in the trees touching limbs and leaves. Although it worked OK it wasn't until I moved it into the clear that I realized how much signal I was loosing having it in the trees. Nearly 3db increase according to RBN after the move. RBN testing was done

Re: Topband: Inverted L in contact with leaves

From: Topband on behalf of N4ZR Sent: Thursday, August 29, 2019 11:23 AM To: topband reflector Subject: Topband: Inverted L in contact with leaves My inverted L is taking shape - about 60 vertical, the rest horizontal. For a couple of months anyway, it is touching a number of leaves

Re: Topband: Inverted L in contact with leaves

Hi Pete You won't have an issue at all. 73, Mike va3mw On Thu, Aug 29, 2019 at 12:24 PM Gary Smith wrote: > I sure don't have any kind of superstation > but I have never been lucky enough to have > a 160 antenna in the clear. All mine have > always not only touched leaves, but are > always

Re: Topband: Inverted L in contact with leaves

I sure don't have any kind of superstation but I have never been lucky enough to have a 160 antenna in the clear. All mine have always not only touched leaves, but are always resting on branches, many branches. I still get out pretty well, I wouldn't worry about a few leaves coming in

Re: Topband: Inverted L in contact with leaves

: Topband on behalf of N4ZR Sent: Thursday, August 29, 2019 11:23 AM To: topband reflector Subject: Topband: Inverted L in contact with leaves My inverted L is taking shape - about 60 vertical, the rest horizontal. For a couple of months anyway, it is touching a number of leaves in the vertical

Topband: Inverted L in contact with leaves

My inverted L is taking shape - about 60 vertical, the rest horizontal.  For a couple of months anyway, it is touching a number of leaves in the vertical section.  I assume that's not a concern, but thought I'd ask before I get a lot of radials down. First short radial is down and MFJ-259

Re: Topband: Inverted L - newbie questions

Jumper was 1 foot. 73, Pete N4ZR Check out the Reverse Beacon Network at , now spotting RTTY activity worldwide. For spots, please use your favorite "retail" DX cluster. On 8/21/2019 12:47 PM, WW3S wrote: Where did you connect the analyzer? You want it as close as

Re: Topband: Inverted L - newbie questions

Where did you connect the analyzer? You want it as close as possible to the feed point, with as little length of coax jumper as possible. Even a 6 ft jumper can skew the results, been there done that Sent from my iPad > On Aug 21, 2019, at 12:36 PM, Jeff Blaine wrote: > > An inverted L

Re: Topband: Inverted L - newbie questions

An inverted L without radials is a random length wire and the measurements are of no meaning until there is a ground system to make up the other half of the antenna. But to Wes point, the 259 and big 160m antennas is a recipe for going nuts.  You don't even need a high powered BC station -

Re: Topband: Inverted L - newbie questions

How many high-powered BC stations do you have around? Wes  N7WS On 8/21/2019 8:55 AM, N4ZR wrote: I just put up an inverted L, with a vertical length of about 60 feet, and a total of 135 feet.  It is fed through 16 turns of RG-400 on a ferrite core at the base. There are, as yet, no radials.

Topband: Inverted L - newbie questions

I just put up an inverted L, with a vertical length of about 60 feet, and a total of 135 feet.  It is fed through 16 turns of RG-400 on a ferrite core at the base. There are, as yet, no radials. Because I was impatient to see what was going on, I grounded the shield to a single copper-plated

Re: Topband: Inverted L loading wire dilemma

] On Behalf Of Dave G4GED via Topband Sent: 14 March 2019 20:06 To: topband@contesting.com Subject: Topband: Inverted L loading wire dialmma For many years my 160m antenna has been a very successful classic 21m tall Inv L mast with a horizontal loading wire. The only problem, a big one, has been

Re: Topband: Inverted L loading wire dialmma

The "witches hat" as you call it makes an excellent top loading medium for Marconi antennas. I use them here on an AM tower with great success in improving the base impedance of a less than 1/4 tower. Care must be taken that these angled down wires are not to long. (I think 30% of the antena

Topband: Inverted L loading wire dialmma

For many years my 160m antenna has been a very successful classic 21m tall Inv L mast with a horizontal loading wire. The only problem, a big one, has been the loading wire getting tangled up in the surrounding trees in very windy weather. Chopping the trees down is not an option and I've had

Re: Topband: Inverted L improvements - Part 3 (now with data)

Todd, have you been tracking your antenna system's performance using reversebeacon after your sunset? I'm guessing that your sunset is circa 0300Z. Last night (Jan 24) you were picked up at 9 western skimmers, perhaps the furthest ones from you being WB6BEE and the VE6's. Based on my

Re: Topband: Inverted L improvements - Part 3 (now with data)

How about even lay it down? Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 1/23/2019 7:14 PM, Jeff Blaine wrote: Disconnect the other antenna.  Let it float. 73/jeff/ac0c alpha-charlie-zero-charlie www.ac0c.com On 23-Jan-19 6:02 PM, Todd

Re: Topband: Inverted L improvements - Part 3 (now with data)

Disconnect the other antenna.  Let it float. 73/jeff/ac0c alpha-charlie-zero-charlie www.ac0c.com On 23-Jan-19 6:02 PM, Todd Goins wrote: Okay, after many requests, on and off list, I disconnected the 43' T 160m antenna at its feed point and for good measure I disconnected the coax feedline

Re: Topband: Inverted L improvements - Part 3 (now with data)

Okay, after many requests, on and off list, I disconnected the 43' T 160m antenna at its feed point and for good measure I disconnected the coax feedline from the system too. It made a pretty substantial difference in the measurements. The 1.5 SWR range is now only about 35 kHz wide but the 2.0

Re: Topband: Inverted L improvements - Part 3 (now with data)

Dont get discouraged by all this for sure What I see as fly in the ointment is another 160 antenna close by with another radial system, Anyone of you gurus ever figure what putting power into a 160 antenna does with another one within feet of it?   Imagine power going out, and right back

Re: Topband: Inverted L improvements - Part 3 (now with data)

As always Frank makes good points.  In my case my one lowly tower is 90 feet from the inverted-L and in fact supports the horizontal wire.  It's much too short to exhibit any resonance near topband, but I have observed an interesting effect. The tower also supports a pair of inverted-vee

Re: Topband: Inverted L improvements - Part 3 (now with data)

Hey Todd, What happens to your Inverted L's SWR curve if you short your other 160m antenna (the 43'-T) to ground, or otherwise detune it somehow?..could be you're onto something..not sure. Wide SWR's like that generally point to huge ground losses. I just can't get over how freeging wide

Re: Topband: Inverted L improvements - Part 3 (now with data)

Message - From: "Todd Goins" To: topband@contesting.com, 676a8e87-aec6-9ead-1297-0bdb1f0a7...@gmail.com Sent: Wednesday, January 23, 2019 9:09:19 PM Subject: Re: Topband: Inverted L improvements - Part 3 (now with data) Both Merv and Guy are correct here. Perhaps this antenna doesn't

Re: Topband: Inverted L improvements - Part 3 (now with data)

Goins Sent: Wednesday, January 23, 2019 4:09 PM To: topband@contesting.com ; 676a8e87-aec6-9ead-1297-0bdb1f0a7...@gmail.com Subject: Re: Topband: Inverted L improvements - Part 3 (now with data) Both Merv and Guy are correct here. Perhaps this antenna doesn't ever have a chance at being any good

Re: Topband: Inverted L improvements - Part 3 (now with data)

Spooks! Haunted soil! ;-) That's probably not the problem. As I mentioned privately, I think uploading some more photos to a free file-sharing service website *and sharing those links here* would help us all to help you solve this. Since photo attachments to the Topband Reflector are not

Re: Topband: Inverted L improvements - Part 3 (now with data)

:09 PM To: topband@contesting.com ; 676a8e87-aec6-9ead-1297-0bdb1f0a7...@gmail.com Subject: Re: Topband: Inverted L improvements - Part 3 (now with data) Both Merv and Guy are correct here. Perhaps this antenna doesn't ever have a chance at being any good due to the suburban area and lot size

Re: Topband: Inverted L improvements - Part 3 (now with data)

Both Merv and Guy are correct here. Perhaps this antenna doesn't ever have a chance at being any good due to the suburban area and lot size that I'm constrained by. Within a 250ft radius (huge!) there is as follows: 80m dipole, 40m dipole, 30m dipole, 20m dipole, 15m dipole, 20m yagi, and the

Re: Topband: Inverted L improvements - Part 3 (now with data)

Regarding the choke construction and implementation. Mike and I have had an offline exchange, with pictures, and I think we have agreed that the choke has been constructed properly per the newest K9YC specifications using a 2.4" Type 31 Fair-Rite toroid and 18 turns of RG400. Also, the 150' long

Re: Topband: Inverted L improvements - Part 3 (now with data)

Your "apparent" and mine are different because it isn't apparent to me that I advocated that.  I offered a possible explanation to what Todd is observing and provided the title of a reference source where he could explore it more fully. I mentioned what I am using and my rational for doing so.

Re: Topband: Inverted L improvements - Part 3 (now with data)

It's possible that the K9YC choke was improperly wound, per my forwarded message from Jim here yesterday. Here is K9YC's updated info on choke baluns. http://k9yc.com/2018Cookbook.pdf 73, Mike www.w0btu.com On Wed, Jan 23, 2019, 1:05 AM Guy Olinger K2AV wrote: > ... > He inserted a K9YC design

Re: Topband: Inverted L improvements - Part 3 (now with data)

What is missing from that discussion about a maximized use of a given investment, is whether that investment however well maximized, is in fact adequate for the particular ground characteristics and circumstances. Four rotten eggs will deliver a rotten omelette no matter what you mix in or how

Re: Topband: Inverted L improvements - Part 3 (now with data)

Exactly! Sent from my iPhone > On Jan 22, 2019, at 7:25 PM, Grant Saviers wrote: > > Al Christman K3LC thoroughly sliced and diced the tradeoffs of number vs > length for given total wire investment is his Mar/Apr 2004 NCJ paper. > > N6LF also has a lot to say. > > Grant KZ1W > >> On

Re: Topband: Inverted L improvements - Part 3 (now with data)

Al Christman K3LC thoroughly sliced and diced the tradeoffs of number vs length for given total wire investment is his Mar/Apr 2004 NCJ paper. N6LF also has a lot to say. Grant KZ1W On 1/22/2019 16:11 PM, Chortek, Robert L. wrote: “Wes cut his radial length to match the vertical L section

Re: Topband: Inverted L improvements - Part 3 (now with data)

Meant to say “should not decrease loss ...” Sorry! Bob AA6VB Sent from my iPhone > On Jan 22, 2019, at 4:11 PM, Chortek, Robert L. > wrote: > > “Wes cut his radial length to match the vertical L section height (see N6LF >> reference). He didn't reduce the number of radials.” > > I didn’t

Re: Topband: Inverted L improvements - Part 3 (now with data)

Way back some where around the original posting did he not say he had 2 160 antennas up and they are close to each other?  a short vertical and this antenna?   If so what is the short vertical doing,  is it floating or grounded or hooked to the ground system yet,  what is its status? Would make

Re: Topband: Inverted L improvements - Part 3 (now with data)

“Wes cut his radial length to match the vertical L section height (see N6LF > reference). He didn't reduce the number of radials.” I didn’t think it was the “shortening” OF the length of the radials that would improve performance e.g. going from 10 125’ radials to 10 55’ radials (in the case

Re: Topband: Inverted L improvements - Part 3 (now with data)

>So, now we're (apparently) recommending he cut back his already minimal radial field..uhhh, really Wes? I agree with Wes' assessment -- as well as him questioning why Rr would increase with an increased number of radials. If Rr is changing significantly with the increase, then something else is

Re: Topband: Inverted L improvements - Part 3 (now with data)

So, now we're (apparently) recommending he cut back his already minimal radial field..uhhh, really Wes? =-Mike VE9AA I started this message a day or so ago. Others have commented since with some similar thoughts, nevertheless, here is my take. Todd you're going the wrong direction.

Re: Topband: Inverted L improvements - Part 3 (now with data)

Have to pay attention to everything he is reporting. He added a feedpoint choke per K9YC at the same time. Which may, depending on the physical connections at his feedpoint, have removed the feedline shield as an alternate “radial” in parallel with the increasing but still not full size radial

Re: Topband: Inverted L improvements - Part 3 (now with data)

On 1/22/2019 8:03 AM, Bruce wrote: You maybe confusing "Radiation Resistance" with "Feed point Resistance". It often will lower "Feed point Resistance", but raise "radiation Resistance". Really?  Why? Wes  N7WS _ Searchable Archives: http://www.contesting.com/_topband -

Re: Topband: Inverted L improvements - Part 3 (now with data)

I started this message a day or so ago.  Others have commented since with some similar thoughts, nevertheless, here is my take. Todd you're going the wrong direction. The feed point resistance should be going down. A 1/4 wave wire vertical should have a radiation resistance(Rr) of around 35

Re: Topband: Inverted L improvements - Part 3 (now with data)

Indeed, that is what I meant to say. On Tue, Jan 22, 2019 at 10:03 AM Bruce wrote: > You maybe confusing "Radiation Resistance" with "Feed point Resistance". > It often will lower "Feed point Resistance", but raise "radiation > Resistance". 73 Bruce > > On 1/22/2019 9:45 AM, Peter Bertini

Re: Topband: Inverted L improvements - Part 3 (now with data)

Todd, The resistive component should be going down with more radials, not up. Maybe you are not measuring it the right way, or something in the radial system could be resonant (which may be a good thing). Normally, with these antennas, lower R is better (less loss). I have just measured a top

Re: Topband: Inverted L improvements - Part 3 (now with data)

>"I would think adding radials would lower the Radiation resistance. Also, the SWR curve should narrow as ground losses are reduced; since the effect of ground loss resistance swamping the results lessens." The base resistance, not the radiation resistance is lowered by adding in radials. At

Re: Topband: Inverted L improvements - Part 3 (now with data)

You maybe confusing "Radiation Resistance" with "Feed point Resistance". It often will lower "Feed point Resistance", but raise "radiation Resistance". 73 Bruce On 1/22/2019 9:45 AM, Peter Bertini wrote: I would think adding radials would lower the Radiation resistance. Also, the SWR curve

Re: Topband: Inverted L improvements - Part 3 (now with data)

I would think adding radials would lower the Radiation resistance. Also, the SWR curve should narrow as ground losses are reduced; since the effect of ground loss resistance swamping the results lessens. At some point I suggest, as others, that you get on for the contest and see what you can

Re: Topband: Inverted L improvements - Part 3 (now with data)

Man, that seems awfully broad! Somewhere, you have losses, my friend. You ARE measuring directly at the feedpoint, aren't you? And with the antenna analyzer FLOATING (not touching you, the earth, or anything else)? FWIW, the K9YC choke I used was about 6 turns of RG-6 wound through 4 or 5

Re: Topband: Inverted L improvements - Part 3 (now with data)

: Topband: Inverted L improvements - Part 3 (now with data) Hello, Per many people's recommendations I added 800ft of radials today. That is 8 x 100ft each.  It made a difference on the analyzer which I'll summarize below. It was dark when I finished but here are a few data points. I think

Re: Topband: Inverted L improvements - Part 3 (now with data)

: Inverted L improvements - Part 3 (now with data) Hello, Per many people's recommendations I added 800ft of radials today. That is 8 x 100ft each. It made a difference on the analyzer which I'll summarize below. It was dark when I finished but here are a few data points. I think it is better

Re: Topband: Inverted L improvements - Part 3 (now with data)

Hello, Per many people's recommendations I added 800ft of radials today. That is 8 x 100ft each. It made a difference on the analyzer which I'll summarize below. It was dark when I finished but here are a few data points. I think it is better. The wide SWR curve still bothers me but the

Re: Topband: Inverted L improvements - Part 3 (now with data)

Fred had to laugh. I fear my son (yeah a ham) will put all my stuff on the lawn with a small bucket for any money they feel it is worth. Use iT! de KG9H > On Jan 21, 2019, at 8:44 AM, wrote: > > Thank You Guy for taking the time for all great the info. > > I have several pieces of RG400

Topband: Inverted L improvements - Part 3 (now with data)

Thank You Guy for taking the time for all great the info. I have several pieces of RG400 none are long enough. I was an airfield electrician for CVG airport. Got some out of planes and some from the FAA I would demo stuff for them. I will be looking for some RG400 on the web to make a few proper

Re: Topband: Inverted L improvements - Part 3 (now with data)

Hi, Fred. You said: "Guy K2AV I'm guessing you don't like rg58 because of the center conductor moving outwards??" Nope. :>)) RG58 is not RG400. That's why I don't like RG58. RG400 is what should be used for winding coax on toroids. RG400 is a currently manufactured item. It is INTENDED to

Topband: Inverted L improvements - Part 3 (now with data)

Hello everyone. I also trying to improve things here on 160 and other bands. Going to make a few chokes. I have wound 8 turns thru 2.4 x2 31 mix but haven't seen any real improvement. Trying to get rid of some birdies. Guy K2AV I'm guessing you don't like rg58 because of the center conductor

Re: Topband: Inverted L improvements - Part 3 (now with data)

Hi Todd, Have a look at the calculator at https://chemandy.com/calculators/return-loss-and-mismatch-calculator.htm This calculator allows me to compute the SWR for your data points, as if the Z zero of the meter was 32 ohms. This is important because so many excellent antennas exhibit raw feed R

Re: Topband: Inverted L improvements - Part 3 (now with data)

Hello, I borrowed a RigExpert analyzer and was able to take measurements that folks were asking for without AM station overload. I also built the K9YC 160m choke (18 turns of RG58 on a type 31 2.4" toroid). That choke is at the feed point of the vertical. The analyzer was connected directly after

Re: Topband: Inverted L improvements - Part 3

E9AA" To: topband@contesting.com Sent: Wednesday, January 16, 2019 7:32:09 PM Subject: Re: Topband: Inverted L improvements - Part 3 Hi Todd and thanks for answering so quickly. I am no expert. (I'm an Electronics Engineering Technologist and a ham for 40+ yrs,fwiw) I won't deb

Re: Topband: Inverted L improvements - Part 3

y, January 16, 2019 7:32:09 PM Subject: Re: Topband: Inverted L improvements - Part 3 Hi Todd and thanks for answering so quickly. I am no expert. (I'm an Electronics Engineering Technologist and a ham for 40+ yrs,fwiw) I won't debate the exact numbers on that table by K3LC referenced by K9YC, (the

Re: Topband: Inverted L improvements - Part 3

Hi Todd and thanks for answering so quickly. I am no expert. (I'm an Electronics Engineering Technologist and a ham for 40+ yrs,fwiw) I won't debate the exact numbers on that table by K3LC referenced by K9YC, (they are experts) but I will tell you that it makes me go "hmmm" (as in a mild

Re: Topband: Inverted L improvements - Part 3

Hi Mike, Yes, it is a space issue. The presentation I was referring to is http://audiosystemsgroup.com/160MPacificon.pdf where it has a table the references a paper by K3LC that has "Optimum Use of Wire On/In Ground Over Average Soil" and it lists 12 radials at 42' each to essentially use a 500'

Re: Topband: Inverted L improvements - Part 3

".have attached 30 insulated wire radials each 42' in length (as suggested in a K9YC presentation referencing a K3LC study in the NCJ) laying on the ground roughly evenly distributed. The paper said that 12 radials would be "adequate" but I had room and materials for 30 so that's what I laid

Topband: Inverted L improvements - Part 3

Thanks to everyone that has written to me on the reflector and via email. I've read everything you've written and hopefully your efforts have helped me or guided me towards getting this antenna working better. I've made some changes, bought some equipment/parts and built some stuff per all of

Re: Topband: Inverted L improvement question

at-ground feed point with Zo ~ > 2000-ohms or so, what sort of improvement might one expect if the radial > field was significantly improved? > > 73 to all - Dick/w7wkr at CN98pi > = > Message: 1 > Date: Mon, 7 Jan 2019 12:07:16 -0500 > From: Guy

Topband: Inverted L improvement question

mprovement might one expect if the radial field was significantly improved? 73 to all - Dick/w7wkr at CN98pi = Message: 1 Date: Mon, 7 Jan 2019 12:07:16 -0500 From: Guy Olinger K2AV To: Todd Goins Cc: TopBand List Subject: Re: Topband: Inverted L improvement question

Re: Topband: Inverted L improvement question - Part 2

I could give other advice but the best that I could offer is to check out Rudy's, N6LF, site: https://www.antennasbyn6lf.com/  Regrettably, this isn't all that he's published so further searching might be in order.  QEX published a series in 2009-2010 of his stuff. In my "Antennas" document

Re: Topband: Inverted L improvement question

Hi, Grant. Your original was posted to the reflector as well, and I'll let this go there as well. 3:1 current imbalance, whether scalar or not, is grotesquely large with 8 evenly spaced elevated equal length radials. I presume you have already looked for connection issues at the center of the

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