Modified inverted L ???
Michael
I'm assembling all the fixings I need for a new antenna. Now that I'm
committed to an inverted L with my balun ONLY one foot away from the earthen
ground spike...
Given that the horizontal section of an inverted L antenna could work
directionally, would it be good to use two wires at the top of the vertical
section ??? This way you would have one horizontal wire running say north
to south and the second horizontal wire angled at 45 deg to run east and
west ???
Michael
Drakefan
configuration but that's a completely different antenna design from an
inverted-L. Otherwise there isn't any real benefit of using two
horizontal wire sections 90-deg apart. It might be worse than one wire
under certain conditions. If you keep the horizontal wire relatively
short (30-50/ft) it won't be that directional, except for perhaps the
highest shortwave frequencies.
Michael
"Drakefan" <Drak...@bluesky.net> wrote in message
news:4IyNj.14585$gT3.2073@trndny02...
Thanx !
I had a feeling that the best thing to do would be to stick with the cook
book inverted L. Both the horizontal and vertical sections will be 30' due
to necessity. That is about the length and height of my house. I also got
a 6' solid brass ground rod and a 2' ground strap to connect to the balun.
I'm hoping it handles noise better then my old Frankenstein wire did.
After I get it all put together, I cant wait to see how it stacks up to my
store purchased G5RV. I plan to use them both. Always nice to have an
alternate to switch to.
Michael
Dave
fact that at some freqs the antenna works broadside, at others it is end
firing. Height above the ground also affects directionality quite a
bit. If you really want something closer to omni, go with a sloper,
rather than an "L".
Burr
"Dave" <nos...@biteme.com> wrote in message
news:S7idnd9nn7nj1JrV...@earthlink.com...
Dave, I have a sloping "L" is that any good.
It works fine for me.
Burr's Radio Shack - http://tinyurl.com/3wuscn
Red Mountain, California / Bulacan, Philippines
Dave
I can hear airplanes from 4,000 miles away.
RHF
Original Subject-Line was : Modified inverted L ???
http://groups.google.com/group/rec.radio.shortwave/msg/59ae516df44825a8
> Michael wrote:
> > Hiya...
>
> > I'm assembling all the fixings I need for a new antenna. Now that I'm
> > committed to an inverted L with my balun ONLY one foot away from the earthen
> > ground spike...
>
> > Given that the horizontal section of an inverted L antenna could work
> > directionally, would it be good to use two wires at the top of the vertical
> > section ??? This way you would have one horizontal wire running say north
> > to south and the second horizontal wire angled at 45 deg to run east and
> > west ???
>
> > Michael
- The math is staggering.
-
- The concept of random wire includes the hard fact that
- at some freqs the antenna works broadside, at others
- it is end firing.
-
- Height above the ground also affects directionality quite
- a bit.
-
- If you really want something closer to omni,
- go with a sloper, rather than an "L".
-
Dave - The same can be said for a Sloper. ~ RHF
{to paraphase}
The concept of Sloper {random wire} Antenna includes the hard
fact that at some freqs the antenna works broadside, at others
it is end firing. Height above the ground and the Angle of Slope
also affects directionality quite a bit.
The Shortwave Radio Listener (SWL) : Sloper Antenna
-versus- Inverted "L" Antenna : The 3:4:5 of It !
Actually consider an Inverted "L" Antenna with a 30 Foot
Vertical-Up-Leg and a 40 Foot Horizontal-Out-Arm : Starting
at 'A' on the Ground going up to 'B' and then out to 'C'.
- = Versus = -
A Sloper Antenna with a Single Sloping Wire 50 Foot long :
Starting at 'A' on the Ground and sloping up and out to 'C'.
Note - That the Two Antennas together form a 3:4:5 Triangle.
* The effective Vertical Dimensions are the same.
* The effective Horizontal Dimensions are the same.
-wrt- The Omni-Directional Properties of both Antennas :
They both perform about the same.
This is especially true for the Shortwave Listener using a
Ground Rod at Point 'A' with a 9:1 Matching Transformer
and Coax Cable feed-in-line.
What's Missing ? - Point 'B' for the Shortwave Radio Listener
(SWL) who does not have/make a Point 'B' in their backyard
-but- Does have both Points 'A' and 'C' the Sloper Antenna is a
very good 'choice' in Shortwave Radio Listener (SWL) Antennas.
While -IF- a Shortwave Radio Listener (SWL) has/can make all
three Points 'A', 'B' and 'C' in their backyard -then- An Inverted
"L" Antenna is a very good 'choice' in Shortwave Radio Listener
(SWL) Antennas.
Again - When the Shortwave Listener uses a Ground Rod at
Point 'A' with a 9:1 Matching Transformer and Coax Cable
feed-in-line with one or both of these SWL Antenna 'choices'.
it don't take a rocket scientist - iane RHF {pomkia}
.
Are You Interested in building a better Shortwave Listening*
(SWL) Antenna ? {SWL Group} => http://tinyurl.com/ogvcf
GoTo => http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
RHF's Standard "Shortwave Radio Listener (SWL) Antennas Group"
Reference Message Signature-Line => http://tinyurl.com/25zbrg
http://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
.
* Remember 55.5% of Shortwave Radio Listening (SWL)
is the Shortwave Antenna =>http://tinyurl.com/ogvcf
.
RHF's Radio Shack in Twain Harte, California -USA-
SHACK INFO =>http://tinyurl.com/2skmxm
Shortwave Radio / Receiver and SWL Antenna Info
.
-=2SKMXM=-
-=25ZBRG=-
SWR3:SWL:INFO
.
Dave
>
>
> This is especially true for the Shortwave Listener using a
> Ground Rod at Point 'A' with a 9:1 Matching Transformer
> and Coax Cable feed-in-line.
>
> What's Missing ? - Point 'B' for the Shortwave Radio Listener
> (SWL) who does not have/make a Point 'B' in their backyard
> -but- Does have both Points 'A' and 'C' the Sloper Antenna is a
> very good 'choice' in Shortwave Radio Listener (SWL) Antennas.
>
> While -IF- a Shortwave Radio Listener (SWL) has/can make all
> three Points 'A', 'B' and 'C' in their backyard -then- An Inverted
> "L" Antenna is a very good 'choice' in Shortwave Radio Listener
> (SWL) Antennas.
>
> Again - When the Shortwave Listener uses a Ground Rod at
> Point 'A' with a 9:1 Matching Transformer and Coax Cable
> feed-in-line with one or both of these SWL Antenna 'choices'.
>
You still have to keep the unshielded part away from dirty mains
electricity or you will pick up noise.
RHF
All-Band Sloping Inverted "L" Antenna -by- Rolf Brevig [LA1IC]
http://www.hamuniverse.com/slopinginvl.html
Put that 4:1 balun, a couple of insulators
and some extra wire to good use!
-source- Ham Universe - http://www.hamuniverse.com/
* The Inverted "L" Antenna : How It Works
* "Magic" Wire Lengths
* Non-Metric {Feet} and Metric {Metres} Calculations
* Tuning Procedure for the Inverted Sloping "L" Antenna
for Amateur Radio Operators.
NOTE - This Sloping Inverted "L" Antenna design uses a
a Ground Mounted Matching Transformer and Ground Rod
at the Feed-Point with a Coax Cable feed-in-line.
Implementing the Low Noise Design Concepts that were
popularized -by- John Doty
READ - SWL Longwire + Low Noise Antenna Connection
+ Grounding Is Key To Good Reception
Three Messages to Read -by- John Doty
http://groups.google.com/group/rec.radio.shortwave/msg/1abc6a2bf8acc12d
Follow the Links/URLs provided in the Message
? Why ? Use the Sloping Inverted "L" Antenna : It only
requires One above ground level Elevated Support Point.
MOD - For the Shortwave Radio Listener (SWL) making one of
these simple Wire Antennas the only "Modification" would be
to use a 9:1 Matching Transformer {Balun, MLB} for Receive
'Only' : Instead of the Amateur Ham 4:1 Balun cited for used
with a Transmitter.
SIZING - The All-Band Sloping Inverted "L" Antenna for the
Shortwave Radio Listener (SWL)
Basic it is simply a "Random" Wire Length to cover the
'available' Space that you have in your Yard : Going from
the ground* to the Apex {High-Point} of the Antenna and
back to the gorund*.
* Note - A Fence-Top may be used at one or both Ends
instead of the ground for Safety or convenience.
For Those Who - Have-to-Have "Numbers" :
* SHORTY - Small Size Lot - Backyard :
Short-Back-Leg = 17.1 Feet for 22m
Long-Front-Leg = 24.5 Feet for 31m
Total Length ~ 41.6 Feet
Apex ~ 15 Feet**
Ground Foot-Print ~ 30 Feet Tip-to-Tip
* AVERAGE - Medium Size Lot - Backyard :
Short-Back-Leg = 24.5 Feet for 31m
Long-Front-Leg = 38.5 Feet for 49m
Total Length ~ 63.0 Feet
Apex ~ 22 Feet**
Ground Foot-Print ~ 46 Feet Tip-to-Tip
* BIGGIE - Large Size Lot - Backyard :
Short-Back-Leg = 38.5 Feet for 49m
Long-Front-Leg = 59.2 Feet for 75m
Total Length ~ 97.7 Feet
Apex ~ 34 Feet**
Ground Foot-Print ~ 71 Feet Tip-to-Tip
** Note - If you are using a Fence-Top or other Supports :
Instead of the surface of the ground : Then add their Average
Height to the Apex to get the 'corrected' Height of the Apex.
Doing-the-Angles of the Sloping Inverted "L" Antenna :
http://www.lerc.nasa.gov/WWW/K-12/airplane/sincos.html
The Angle of the Apex should be around 90 Degrees; with
the Starting Angle of the Short-Back-Leg at Ground to the
Apex about 60 Degrees; and the Ending Angle at Ground
of the Long-Front-Leg from the Apex to Ground about 30
Degrees.
FWIW - I call this Sloping Inverted "L" Antenna a
Lazy Inverted "L" Antenna because the "L" is too
'Lazy' to Stand Up-Side-Down {Inverted} :o) ~ RHF
Be it Sloping or Lazy - It's sort of an 'L' - iane RHF {pomkia}
.
Are You Interested in building a better Shortwave Listening*
(SWL) Antenna ? {SWL Group} => http://tinyurl.com/ogvcf
GoTo => http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
RHF's Standard "Shortwave Radio Listener (SWL) Antennas Group"
Reference Message Signature-Line => http://tinyurl.com/25zbrg
http://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
.
* Remember 55.5% of Shortwave Radio Listening (SWL)
is the Shortwave Antenna =>http://tinyurl.com/ogvcf
.
RHF's Radio Shack in Twain Harte, California -USA-
SHACK INFO =>http://tinyurl.com/2skmxm
Shortwave Radio / Receiver and SWL Antenna Info
.
-=2SKMXM=-
-=25ZBRG=-
SWR3:SWL:INFO
.
On Apr 17, 7:49 am, RHF <rhf-newsgro...@pacbell.net> wrote:
> - = S N I P = -
> Reference Message Signature-Line =>http://tinyurl.com/25zbrghttp://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
RHF
>
> - Show quoted text -
Dave - TGWOS ~ RHF
.
RHF
> On Apr 18, 5:54 am, Dave <nos...@biteme.com> wrote:
>
>
> > RHF wrote:
>
> > > This is especially true for the Shortwave Listener using a
> > > Ground Rod at Point 'A' with a 9:1 Matching Transformer
> > > and Coax Cable feed-in-line.
>
> > > What's Missing ? - Point 'B' for the Shortwave Radio Listener
> > > (SWL) who does not have/make a Point 'B' in their backyard
> > > -but- Does have both Points 'A' and 'C' the Sloper Antenna is a
> > > very good 'choice' in Shortwave Radio Listener (SWL) Antennas.
>
> > > While -IF- a Shortwave Radio Listener (SWL) has/can make all
> > > three Points 'A', 'B' and 'C' in their backyard -then- AnInverted
> > > "L" Antenna is a very good 'choice' in Shortwave Radio Listener
> > > (SWL) Antennas.
>
> > > Again - When the Shortwave Listener uses a Ground Rod at
> > > Point 'A' with a 9:1 Matching Transformer and Coax Cable
> > > feed-in-line with one or both of these SWL Antenna 'choices'.
- - ???
- -
- - You still have to keep the unshielded part away
- - from dirty mains electricity or you will pick up noise.
- Dave - TGWOS ~ RHF
- .
David - That Goes With Out Saying ~ RHF
SWL -Newbies- Installing an Inverted "L" Antenna : The Right-Way !
Wellbrook "Low Noise Antenna" 'design concept' using two
components they manufacture: the Universal Magnetic Balun
(UMB) and the Antenna Feed Isolator (Feed-Line-Isolator).
http://www.wellbrook.uk.com/longwire.html
FWIW - This webpage has two Drawings / Diagrams :
"The Wrong Way" -and- "The Correct Way"
plus a brief description of the 'Whys' and 'Hows'
of this "Low Noise Antenna" design concept.
NOTE - These are labled as "Longwire" Antenna Baluns,
but in reality they are mostly used on the more common
"Random Wire" Antennas that the majority of SWLers
are able to build and use in their backyards or outside /
inside the house.
AGAIN - The Right-Way {and Wrong-Way} to Install
a LongWire {Random Wire} Antenna.
http://www.wellbrook.uk.com/longwire.html
Low Noise Longwire Antenna using the UMB -by- Wellbrook.
http://groups.google.com/group/rec.radio.shortwave/msg/735cc467b35a70d5
The "Correct Way" to Install a Longwire Antenna and Balun
by Wellbrook - Using the Far-End Feed-Point Concept
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/11773
The "Correct Way" to Install a Longwire Antenna and Balun
by Wellbrook => http://www.wellbrook.uk.com/longwire.html
We have all most likely done it the wrong way more than once . . .
A 'key-point' that Wellbrook makes is the Five Metre (5m)
"Noise Zone" that exists around a House and getting the
Wire Antenna Element away {out} from this area.
http://www.wellbrook.uk.com/longwire.html
NOTE - The above "Correct Way" installation will ensure
that the Wire Antenna Element is 'outside' the local
Noise Zone which extends up to Five Metres (16 Feet)
around the House. Also the noise pickup is lower with
the feeder close to the ground -or- buried under the
ground a few inches.
-Why- The Antenna and the Balun are within the Local
Noise Zone RFI & EMF {Interference Area} that surrounds
most buildings up to distance of Five Metres (16 Feet).
Read - WHY - The Far-End-Fed Shortwave Listener's
(SWLs) Inverted "L" Antenna
http://groups.google.com/group/rec.radio.shortwave/msg/22cfc6b9cb2447c0
all i ask for is five metres beyond the noise - iane ~ RHF {pomkia}
.
Are You Interested in building a better Shortwave Listening*
(SWL) Antenna ? {SWL Group} => http://tinyurl.com/ogvcf
GoTo => http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
RHF's Standard "Shortwave Radio Listener (SWL) Antennas Group"
Reference Message Signature-Line => http://tinyurl.com/25zbrg
http://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
.
* Remember 55.5% of Shortwave Radio Listening (SWL)
is the Shortwave Antenna =>http://tinyurl.com/ogvcf
.
RHF's Radio Shack in Twain Harte, California -USA-
SHACK INFO =>http://tinyurl.com/2skmxm
Shortwave Radio / Receiver and SWL Antenna Info
.
-=2SKMXM=-
-=25ZBRG=-
SWL:NEWBIE:INFO
.
RHF
>
> Hiya...
>
> I'm assembling all the fixings I need for a new antenna.
> Now that I'm committed to an inverted L with my balun
> ONLY one foot away from the earthen ground spike...
>
- Given that the horizontal section of an inverted L antenna
- could work directionally, would it be good to use two wires
- at the top of the vertical section ???
Michael,
Single Wire Vertical-Up-Leg 'connected' somewhere near
the Center {Off-Center} of a Horizontal Wire is basically a
* "T" Antenna
http://www.aa5tb.com/t_vert13.gif
* -or- Windom Antenna.
http://www.x-net.idv.tw/bv3fg/swl/windom.gif .
http://www.g3woe.com/G3WOE/Windom.html .
http://www.dxengineering.com/images/HtmlTechImages/CCBalun_Diagram.gif
Double Parallel Twin-Wire Vertical-Up-Leg 'connected'
somewhere near the Center {Off-Center} of a Horizontal
Wire is basically a G5RV Antenna -or- Balanced Feeder
Dipole of sorts . http://www.wimo.com/bilder/11385.gif .
http://www.astrosurf.com/luxorion/qsl-g5rv-2.htm .
http://www.kyes.com/antenna/antennatypes/twinlead.jpg .
http://kalx.berkeley.edu/recept/images/dipolbld.gif .
http://www.dxengineering.com/images/HtmlTechImages/BFwindom_Balun.gif
- This way you would have one horizontal wire running say
- north to south and the second horizontal wire angled at
- 45 deg to run east and west ???
-
- Michael
Michael - North-to-South -versus- East-to-West is 90 Degrees.
About : Modifying the Inverted "L" Antenna :
* The "T-L" Antenna
* The Wind-L Antenna
* The Bi-Polar-L Antenna
=equals= It Ain't an "L
-or- The "L" If I Know !
Beyond The "L" - What Shape Is Your SWL Antenna ?
QUESTION - Will Changing the Physical Structure {Lay-Out}
of the Inverted "L" Antenna also change it's Radio Reception
Characteristics : Well May-Be ?
-and- Most Likely Yes on many/most Frequencies.
a b c d e f g h i j k "L" m n o p q r s t
u v w x y z - iane ~ RHF {pomkia}
Telamon
<7d8a3afd-badf-4df2...@q24g2000prf.googlegroups.com>,
RHF <rhf-new...@pacbell.net> wrote:
> On Apr 18, 12:22 pm, RHF <rhf-newsgro...@pacbell.net> wrote:
> > On Apr 18, 5:54 am, Dave <nos...@biteme.com> wrote:
> >
> >
> > > RHF wrote:
< SNIP >
Nothing interesting. Nothing useful.
--
Telamon
Ventura, California
m II
>>>> RHF wrote:
>
> < SNIP >
>
> Nothing interesting. Nothing useful.
Completely unlike your response to him.
mike
Telamon
<e28bc31d-7c71-4a3b...@f24g2000prh.googlegroups.com>,
RHF <rhf-new...@pacbell.net> wrote:
> On Apr 16, 6:20 pm, "Michael" <md1...@optonline.net> wrote:
> >
> > Hiya...
> >
> > I'm assembling all the fixings I need for a new antenna.
> > Now that I'm committed to an inverted L with my balun
> > ONLY one foot away from the earthen ground spike...
> >
>
> - Given that the horizontal section of an inverted L antenna
> - could work directionally, would it be good to use two wires
> - at the top of the vertical section ???
>
> Michael,
>
> Single Wire Vertical-Up-Leg 'connected' somewhere near
> the Center {Off-Center} of a Horizontal Wire is basically a
> * "T" Antenna
< SNIP >
So he would only get "T" polarized signals right? No, no wait a minute,
he would get "L" polarized signals. This is so confusing. I know there
is a dead chicken in here somewhere.
--
Telamon
Ventura, California
RHF
<telamon_spamshi...@pacbell.net.is.invalid> wrote:
> In article
> <e28bc31d-7c71-4a3b-a62d-aeeb17b10...@f24g2000prh.googlegroups.com>,
>
>
>
>
>
> RHF <rhf-newsgro...@pacbell.net> wrote:
> > On Apr 16, 6:20 pm, "Michael" <md1...@optonline.net> wrote:
>
> > > Hiya...
>
> > > I'm assembling all the fixings I need for a new antenna.
> > > Now that I'm committed to an inverted L with my balun
> > > ONLY one foot away from the earthen ground spike...
>
> > - Given that the horizontal section of an inverted L antenna
> > - could work directionally, would it be good to use two wires
> > - at the top of the vertical section ???
>
> > Michael,
>
> > Single Wire Vertical-Up-Leg 'connected' somewhere near
> > the Center {Off-Center} of a Horizontal Wire is basically a
> > * "T" Antenna
>
> < SNIP >
>
minute,
- he would get "L" polarized signals. This is so confusing. I know
there
- is a dead chicken in here somewhere.
-
- --
- Telamon
- Ventura, California
Teli - With the "T" Antenna he can get El Telamondo ! ~ RHF
.
Telamon
I could say the same about you and in fact I just did.
You have anything to contribute to the news group? Nope.
--
Telamon
Ventura, California
Telamon
<a870a27a-2982-45fb...@w5g2000prd.googlegroups.com>,
RHF <rhf-new...@pacbell.net> wrote:
> Teli - With the "T" Antenna he can get El Telamondo ! ~ RHF
> .
Wow, the obvious answer went right over my head. Looking at your
subject line I was thinking more along the lines of a Tilted Bi-Polar
Chicken that had wind from eating moldy corn or something worse. That
would be a TBPC antenna.
--
Telamon
Ventura, California
Michael
"RHF" <rhf-new...@pacbell.net> wrote in message
news:a870a27a-2982-45fb...@w5g2000prd.googlegroups.com...
*************************************************************************************
I was all set to use a 6' solid brass spike into the Earth, but then I
remembered your recommendation. I ditched the 6' solid brass rod and used
some nylon strapping to secure a whole uncooked chicken to the brick
chimney. I did it in the rain, so I had to work quick. When I had the
chicken strapped on, I ran the receiving wire before I connected the ground
strap from the balun to the chicken. Just as I was hooking the ground strap
up from the balun to the chicken, the receiving wire got hit by lighting.
It fried the chicken and blew me off the roof. I landed flat on my back and
coughed up my Viagra. I need to get back up on the roof and try again.
Will a cooked chicken work as good as a raw one ???
Michael