I feel it more appropriate to say that the function of ground-mounted radials
is to harvest the radiation from a vertical antenna that splashes on the ground
and return it to the feed point for recycling.
72/73,
Charles, W2SH
From: Topband on behalf of Jim
Bro
I would prefer to have the horizontal radiation canceled by using an inverted
T, but I haven't discovered a workable configuration to achieve that.
Therefore I use an inverted L with a vertical leg of 86', the most I can get.
I have no serious limitations on the length of the horizontal leg an
From: Charles Moizeau
Sent: Tuesday, February 18, 2020 18:00
To: g...@ka1j.com
Subject: Re: Topband: Dacron & varmits
I have for years used the polyester (Dacron is a polyester branded by the
Dupont company) products of Synthetic Textiles of Anaheim CA.
Wayne,
Ditch the idea of using the tennis ball launcher. Neither it nor the Zebco
spinning reel will solve your problem which is basically to get your projectile
to reach the target but not go much further beyond it, either into a danger
zone or into some other tree.
Here's my technique. Get
David,
Like you I support the petition. However, I will lend my name to it because I
don't want to selfishly chicken out for all the valid reasons you note.
Heck, it was only last week that Medicare, after many years, sent me a new
card, proudly announcing how pleased they now are with the f
With in-ground, which optimally should be be so shallow as to be on-ground,
radials there's no thought or effort needed to think about them as being
anything close to the intended radiation frequency.
But with elevated radials my understanding, and it is more nonexistent than
limited because I
The function of radials is to collect the radiation from your antenna that
splashes on the ground and deliver it back to the antenna feedpoint for
recycling. As such, if you decide to trench into the hard subsoil, don't go
deep. Alternatively, you can lay the radials on top of that hard layer
Another choice, and one more durable than the zinc-dipped steel of chicken
fencing, and probably less expensive than copper mesh, is rabbit/deer fencing.
This is available in different gauges and different sizes. It is steel but
with a thick coating of pvc. A typical size of its openings is 2"
to the feedpoint.
Charles, W2SH
From: Mark K3MSB
Sent: Sunday, February 18, 2018 7:40 PM
To: Charles Moizeau
Cc: Mike Waters; Roger Kennedy; topband@contesting.com
Subject: Re: Topband: 1/2 wave inv L
I've read that the minimum lengths for ground radials is no shorter than the
height o
Well it is understandable. The current maximum in the half-wave antenna is
lifted well above ground level. Had there been a radial system it would have
had to employ very long radials, for most of the vertical's radiation would
have been hitting the ground at points far away from the base of t
Years ago I tried a a weather balloon filled with hydrogen from a hired
canister. The balloon's spherical shape made it highly susceptible to being
disturbed by even a fairly mild breeze. In my case the vertical wire was
tilted well away from being vertical. Fairly soon the balloon met the br
Yes, the maximum quantity of total current in the vertical section of an
inverted T, or inverted L antenna is achieved when the antenna's current loop
is placed at the center of the vertical leg. As in all antennas this current
loop is located a quarter wavelength back from an open end.
Howev
30 miles west of NYC, their carrier is S9 plus 25 dB with music faintly
audible. This on an inverted L.
Charles, W2SH
From: Topband on behalf of Bill Stewart
Sent: Wednesday, January 10, 2018 5:59 PM
To: topband
Subject: Topband: WKYW on 1810kc
Is anyone c
That could be true, but for several years my inverted L (86 feet up and 68 feet
out, over 1.5 miles of in-ground radials) is significantly less noisy on
receive than my 270-foot center-fed dipole sloping (intentionally) from 83 feet
to 7 feet.
Your comments please.
73,
Charles, W2SH
_
My earlier message should properly have read, "The free-space pattern of
current in a HALF WAVELENGTH vertical (and also horizontal) antenna..."
From: Charles Moizeau
Sent: Monday, July 3, 2017 6:09 PM
To: Herbert Schoenbohm; TopBand List
Subject: Re: Topband: 160 meter 1/4 vertic
The free-space pattern of current in a vertical (and also horizontal) antenna
is crescent shaped with its maximum at the midpoint, and a minimum at each end.
It shows nothing that could be termed an extraneous lobe. Any such lobes
would seem to be the result of improper matching, or more like
The two big-box home improvement stores carry more expensive, heavy-duty garden
hose, some with 5/8" and maybe 3/4" IDs. that might be used to protect a
moderately long run of coax.
I have some galvanized steel "hardware cloth" (I think) with 1/2" squares that
I use to cover some rain water dr
From: Charles Moizeau
Sent: Tuesday, November 8, 2016 12:32 PM
To: farr...@yahoo.com
Subject: Re: Topband: 160 m inverted L
An advantage of having the total length of the inverted L antenna at greater
than 0.25 wavelength is that matching to coax at its base can be achieved with
just a
Before putting any kind of tape, gunk or goo on a fitting or soldered
connection with the expectation of weatherproofing it in an outdoor
environment, I ALWAYS do this first: I wrap the item with two layers of
half-inch wide 3-M blue tape used by painting contractors and widely available.
Thi
Thanks Lloyd,
But pls tell us your wire height and approximate description of gnd condx for
your otherwise well-described bog.
73,
Charles W2SH
From: Topband on behalf of Lloyd - N9LB
Sent: Sunday, October 16, 2016 7:15 PM
To: topband@contesting.com
Sub
ea6vq...@dxmaps.com
Gabriel,
View two products from MFJ enterprises, MFJ-1707 and MFJ-1708.
73,
Charles, W2SH
***
From: Topband on behalf of Gabriel - EA6VQ
Sent: Thursday, Sept
Bruce,
"...in my area, the most stable earth moisture is at grass/vegetation root
level..."
Are you are in fact saying that to be "stable", that is to say, remain the same
day in, day out, a "BOG" needs to be evenly sunk to about not more than one
inch below the perceived surface?
73,
Charles
Gary,
Given the 50' maximum height of a presumably level catenary line supported at
its ends, there are two things you can do to significantly improve the
performance of the 50' vertical wire hanging below.
1. Obtain a stout piece of bamboo. Try to make at least a 10' long pole, and
this
Stew was a magnificently correct person.
His distinctive white lettered callsign on a background gracing his slightly
oversize, but legal to suit USPS size limits, QSL card is wall candy in my
shack.
Were I to examine my 1973 logbook, I'm certain it would show "W1BB/1" for our
Field Day QSO, a
Incorrect date and day. According to NAQCC their annual NAQCC 160m sprint will
occur in North America on FRIDAY, 15 January 2016. This can be seen at:
http://www.naqcc.info/SprintEastern.txt
72,
Charles, W2SH
> Date: Sat, 5 Dec 2015 14:49:47 -0500
> From: tsho...@gmail.com
> To: j...@audios
I am 30 miles due west of NYC. I receive it plenty loud on 1.810540 mHz. For
a while this evening I experienced only about +/- 5dB of QSB , but now that QSB
is running +/- 15 dB. Therefore it's got to be a good bit of sky wave reaching
me.
I don't have directional receiving capability. Wil
I would be grateful to learn from readers particulars of these relays, such as:
whether used in connection with receiving or transmitting antenna systems,
operating coil voltage, maximum rated current and voltage through the contacts,
and perhaps manufacturers' names and model numbers. Also, h
Herb's suggestion is worthy, but needs a qualification as to the kind of tape
to use.
Over time the adhesive layer of just about all tape will separate from the tape
itself. This will happen when installed in the field or even if left for a
couple of years or more on an indoor shelf. The res
>This link http://www.commtechrf.com/documents/nab1995.pdf leads to a paper
>by Clarence Beverage with some real-world results for monopoles with
>elevated wires used as a counterpoise.
***
Towards the end of the above reference mention was mad
The February and April 2012 issues of RadCom (Radio Society of Great Britain's
monthly publication) treat the matter of interference from LED lighting. A 4W
LED spotlight, with three series-connected LED bulbs, powered by a miniature
switch-mode power supply that supplies 9.2 vdc from the 2
Nope.
With 100 Ohms per radial and 60 of them all the same and in parallel with each
other, one gets 1.6 Ohms; close enough.
73,
Charles, W2SH
> From: royan...@ncn.net
> To: topband@contesting.com
> Date: Mon, 30 Jan 2012 12:15:10 -0600
> Subject: Re: Topband: T vert feed
>
> 'Twas sta
hich is the ultimate common mode current block.
73, Guy
On Fri, Jan 27, 2012 at 11:40 AM, Charles Moizeau wrote:
My radial field consists of 55 radials, 75' to 150' in length, buried 0.5" to
1" deep. My coax feedline, encased by a 1.25" gray pvc conduit, is 12
limit how much isolation can be
> achieved this way?
>
> 73, Pete N4ZR
> The World Contest Station Database, updated daily at www.conteststations.com
> The Reverse Beacon Network at http://reversebeacon.net, blog at
> reversebeacon.blogspot.com,
> spots at telnet.reversebeac
My radial field consists of 55 radials, 75' to 150' in length, buried 0.5" to
1" deep. My coax feedline, encased by a 1.25" gray pvc conduit, is 12'' deep
and 80' long. It passes beneath several radials between the shack and the
antenna base.
I don't use a common-mode choke at the base feedp
I should like to offer comments on and some alternative
recommendations for the described construction of the 66-foot long FCP.
It has already been pointed out that the commercially
manufactured “450-Ohm open-wire line” is not suitable for the counterpoise.
That is indeed true. A yardstic
> Date: Tue, 22 Nov 2011 15:20:00 -0500
> From: olin...@bellsouth.net
> To: w...@suddenlink.net
> CC: topband@contesting.com
> Subject: Re: Topband: Counterpoise very interresting
>
> Extract:
>I found LB to be a little enigmatic...I'm fairly sure he did not have the
>health for the hard ou
For one of the early ARRL Topband contests in the 1970s I, then as WB2URU,
rented a tank of helium and inflated a World War 2 surplus balloon to support a
quarter-wave vertical. Everything went well until the balloon reached a
height of about 80 feet. At that altitude there was enoug
Buzz,
Instead of 500-foot rolls of insulated wire, I found it more cost effective to
buy a 1,000-foot roll of 14-2 with ground wire from Home Depot. I stretched
about 200 feet at a time along my property. From an electrical supply house I
bought an inexpensive tool that zips easily through t
> From: wesatta...@bellsouth.net
> To: dj...@kcag.de; topband@contesting.com
> Date: Thu, 13 Oct 2011 12:23:41 -0500
> Subject: Re: Topband: Capacitor for Inverted L
>
> The question of "matching" an Inverted-L comes up every now and then, and
> under some circumstances it may be necessary to ins
> Date: Sat, 17 Sep 2011 17:38:09 -0500
> From: mikew...@gmail.com
> To: topband@contesting.com
> Subject: Re: Topband: Effect of current max not at base of vertical.
>
> Guy,
>
> I'm not saying that I understand this 100%, but I certainly do find it
> fascinating. I have a question, though.
>
In my most recent posting on this subject I said:
"...I'm puzzled by how the feed current at the base of any antenna, regardless
of its length, will always be at a maximum at its base. A half-wavelength
antenna presenting a few thousand ohms of input impedance at its base would, I
thi
My comment on this subject is directed to KM1H who in a recent posting said:
> > I used 4' x 50' rabbit mesh (2x4") that was welded, then galvanized and
> > then
> > plastic dipped for over 10 years at a prior QTH. It was purchased that way
> > at a garden store.
> >
> > Galvanizing is very eas
Jorge,
The short answer is the 120 18-gauge radials will be much
more effective than the 40 radials.
Consider two absurd examples: 1) all 120 radials are
connected in parallel and laid in a single shallow trench; 2) all 120 radials
are connected in series and laid in a single shallow trench
Jorge,
It has been my experience at this QTH in NJ that soldered connections outdoors
do not do well with solder that contains lead. Over time the connections all
turn dull and often the solder on a well-soldered joint will crumble over time.
For this reason all my outdoor soldered connection
A careful reading of Rudy's piece does show that in a situation where you are,
and must remain, totally compromised throughout a 180-degree sector, i.e.,
with zero radials, you can at least pick up from the deficient direction 0.52
dB (-1.39 dB vs. -1.91 dB, in his cases C7 vs. C3) just by int
Paul,
I will certainly second Jeff's recommendation.
Those gray plastic junction boxes are made for outdoor use and are heavy-duty
construction. They come in various sizes with the cover equipped with a
flexible gasket.
I get mine from Lowes, but don't recall the manufacturer. Of course I
On Fri, 1 Apr 2011 01:03:17 -0400
George, AA7JV, wrote:
>...Last night I worked OK1TN with 5W(QRP) from Florida with no difficulty. It
>was like an
> 40m QSO. The band was great! March/Apr are great times on 160...!
It seems to me that the days around the vernal equinox have always been good
I'd be grateful to learn the preferences of users of these devices.
My set-up is 50-Ohm, 0.405" diameter (Wireman X-4XL) coaxial cable,
underground, but within electrical pvc conduit. This attaches through a PL-259
to a DX Engineering radial attachment plate. The antenna is an inverted L with
> Date: Mon, 10 Jan 2011 14:25:26 -0500
> From: olin...@bellsouth.net
> To: k...@pacbell.net
> CC: topband@contesting.com
> Subject: Re: Topband: Russian Vacuum Variables on EBAY
>
> Bought two 1200 pf 4 kV for use on big 160 antennas out at N4AF, from
> QRO-stuff. No problems and have done
Eddy,
Interest is also on a sharp increase in the other direction. This week the
traffic on QRP-L has been very heavy on the subject of 600m, where a few
authorized experimental stations are active and there seems certainty over it
becoming generally open to US amateur radio licensees. Of si
50 matches
Mail list logo
