Here are the dimensions for the top hat that I'm going to use (I need Ch.7). Top 18.6",down 1", in (both sides) 2", down 0.8" out 4.5"(both sides). It will be 0.4" (10mm) above the stubs on the GH.
Area 51 for Antenna Modelers & Builders (See Post #1)
This thread has been created strictly for Antenna Modelers and Builders who like to live not just on the leading edge but on the bleeding edge of antenna research and development.
Area 51 is for posting and discussion of any computer model of any experimental antenna by Antenna Modelers and Builders
Area 51 is not for casual builders or newcomers to ask questions or look for useable home antennas. Participants here are expected to fairly well "know their stuff".
If an antenna design is shown to be worthwhile for general public consumption we will move it out of Area 51 into the main Antenna Research & Development Forum.
Just remember what the ancient map makers wrote when they had no further info to illustrate: "Beyond here be dragons!"
Area 51 is for posting and discussion of any computer model of any experimental antenna by Antenna Modelers and Builders
Area 51 is not for casual builders or newcomers to ask questions or look for useable home antennas. Participants here are expected to fairly well "know their stuff".
If an antenna design is shown to be worthwhile for general public consumption we will move it out of Area 51 into the main Antenna Research & Development Forum.
Just remember what the ancient map makers wrote when they had no further info to illustrate: "Beyond here be dragons!"
221 - 240 of 1328 Posts
This is somewhat surprising. Using the Top Hat NAROD on the SBGH gen 1, 89mm feedpoint, No Reflectors example above, I compared using a Top Hat NAROD reflector versus a straight NAROD reflector (for channels 10 - 13) and got this:
I was really expecting the NAROD reflector with the same shape as the Top Hat NAROD to have the better gain. Either way, its a healthy increase with a NAROD reflector. The simple straight one looks to be a bit better and no change in the dip.
(the reason I chose the SBGH gen1 to example with is that unlike JEDs designs, the uhf reflectors arent above the stubs. That could complicate things later on. Also, my meaning of the correct direction on a reflectorless SBGH means the NAROD is in front of the NAROD reflector towards the transmitter, heh.)
Code:
Top Hat NAROD reflector 10 inch spacing
Raw
Mhz Gain SWR
--- ---- ----
195 7.95 2.19 Note: gain direction is flipped, 6.33dBi in the correct direction
201 9.04 2.26
207 9.98 2.78
213 9.00 2.35
Straight 28 inch NAROD reflector 10 inch spacing
Raw
Mhz Gain SWR
--- ---- ----
195 8.7 1.71 Note: The gain direction is not flipped.
201 10.1 2.32
207 9.9 2.75
213 9.3 2.77(the reason I chose the SBGH gen1 to example with is that unlike JEDs designs, the uhf reflectors arent above the stubs. That could complicate things later on. Also, my meaning of the correct direction on a reflectorless SBGH means the NAROD is in front of the NAROD reflector towards the transmitter, heh.)
Quote:
Running the NEC 2NEC4 complains about unequal segmentation of the parallel segments. Not sure if this is valid or a bug. To me the segments are equally segmented but maybe I am missing something? /Quote
To me the segments look equal too, after saving in Geometry Edit. It must be in the segmentation the SY cards do. I seem to recall someone else mentioning that on the 4nec2 forum.
Maybe its fixed in the update ?RELEASE NOTES
Changes for 5.7.5 (9 Jul 2009)
- Bugfix in variable sweeper when having specified a freq-sweep in the Nec input-file.
- Bugfix in optimizer when using 'fast-ground'together with radial groundscreen.
- Bugfix for duplicate NT lines in 'new Nec editor' when only empty lines were entered.
- Problem fixed when starting Notepad/Wordpad programs on case-sensitieve Windows-95 systems.
- Bugfix when updating surface-patch continuation data (SC card) from withing new Nec-editor.
- Bugfix for accidentally introduced bug (to fix below TL-tag problem) in RLC-matching window (F10).
- Bugfix for percentual TL tag/segment number positioning.
- Few other minor fixes.
I Have to check it out, thanks for the tip.Maybe its fixed in the update ?
Another junk U tube antenna Bad design
DO not build
CE u-tube
GW 1 3 0 -1.05 0 0 1.05 0 0.04
GW 2 9 0 -1.05 0 0 -1.05 6.5 0.04
GW 3 9 0 -1.05 6.5 0 -1.55 0 0.04
GW 4 6 0 -1.55 0 -0.1 -2.1 4.8 0.04
GW 5 6 0 -2.45 7.66 0 -7.35 7.66 0.04
GW 6 9 0 -7.35 7.66 0 -7.35 0 0.04
GW 7 7 0 -7.35 0 0 -2.25 0 0.04
GW 8 11 0 -2.25 0 0 -2 7.66 0.04
GW 9 5 0 -2 7.66 0 2 7.66 0.04
GW 10 11 0 2 7.66 0 2.25 0 0.04
GW 11 7 0 2.25 0 0 7.35 0 0.04
GW 12 11 0 7.35 0 0 7.35 7.66 0.04
GW 13 7 0 7.35 7.66 0 2.45 7.66 0.04
GW 14 11 0 2.45 7.66 -0.1 2.1 4.8 0.04
GW 15 9 0 1.55 0 0 1.05 6.5 0.04
GW 16 9 0 1.05 6.5 0 1.05 0 0.04
GW 17 3 -0.1 -2.1 4.8 0 -2.45 7.66 0.04
GW 18 3 -0.1 2.1 4.8 0 1.55 0 0.04
GS 0 0 0.0254
GE 0
EK
LD 5 0 0 0 5.8e7 0
EX 0 1 2 0 1 0
GN -1
FR 0 1 0 0 470 0
XQ
EN
Edit: It look very much like a "Joe Carr" Six Shooter.
DO not build
CE u-tube
GW 1 3 0 -1.05 0 0 1.05 0 0.04
GW 2 9 0 -1.05 0 0 -1.05 6.5 0.04
GW 3 9 0 -1.05 6.5 0 -1.55 0 0.04
GW 4 6 0 -1.55 0 -0.1 -2.1 4.8 0.04
GW 5 6 0 -2.45 7.66 0 -7.35 7.66 0.04
GW 6 9 0 -7.35 7.66 0 -7.35 0 0.04
GW 7 7 0 -7.35 0 0 -2.25 0 0.04
GW 8 11 0 -2.25 0 0 -2 7.66 0.04
GW 9 5 0 -2 7.66 0 2 7.66 0.04
GW 10 11 0 2 7.66 0 2.25 0 0.04
GW 11 7 0 2.25 0 0 7.35 0 0.04
GW 12 11 0 7.35 0 0 7.35 7.66 0.04
GW 13 7 0 7.35 7.66 0 2.45 7.66 0.04
GW 14 11 0 2.45 7.66 -0.1 2.1 4.8 0.04
GW 15 9 0 1.55 0 0 1.05 6.5 0.04
GW 16 9 0 1.05 6.5 0 1.05 0 0.04
GW 17 3 -0.1 -2.1 4.8 0 -2.45 7.66 0.04
GW 18 3 -0.1 2.1 4.8 0 1.55 0 0.04
GS 0 0 0.0254
GE 0
EK
LD 5 0 0 0 5.8e7 0
EX 0 1 2 0 1 0
GN -1
FR 0 1 0 0 470 0
XQ
EN
Edit: It look very much like a "Joe Carr" Six Shooter.
4nec2 refused to run due to segmentation problems....GW14 has way too many.
I made fol. changes so L and R sides match up:
GW17 from 3 to 5, GW14 from 11 to 5 and GW18 from 3 to 6.
Autosegmenter gives significantly different results, depending on chosen segment number,
so I didn't go that route...
Since the Azimuthal pattern is max towards 240-deg at 174 MHz, 4nec2's Gain curve
is for that direction. The Gain towards 90-deg can be seen in the Azimuthal plot by
hitting the "J" key and navigate freq & azimuth via arrow keys. To PLOT the Gain curve
towards 90-deg, enable the FP statement below for "1D Gain" and comment out the
"2D Azimuthal Gain Slice" statement (a single quote mark, as shown below).
Gain is 3.0 dBi (174 MHz), rising to 8.5 dBi (566 MHz) and falling to 3.7 dBi (698 MHz).
But the SWR starts at 6, has a very narrow dip to 1.06 at 566 MHz and quickly jumps
to 22, so it's excessive over most of the UHF band, which can cause problems in many
situations, depending on cable length and other factors.
So, like many U-Tube wonders, it has some Raw Gain but is inherently defective....
Modified 4nec2 file:
CM Yet another U-Tube Defect, 4nec2 by Xauto, 24July2009
CM Segmentation corrected by holl_ands
CE
GW 1 3 0 -1.05 0 0 1.05 0 0.04
GW 2 9 0 -1.05 0 0 -1.05 6.5 0.04
GW 3 6 0 -1.05 6.5 0 -1.55 0 0.04
GW 4 6 0 -1.55 0 -0.1 -2.1 4.8 0.04
GW 5 6 0 -2.45 7.66 0 -7.35 7.66 0.04
GW 6 9 0 -7.35 7.66 0 -7.35 0 0.04
GW 7 7 0 -7.35 0 0 -2.25 0 0.04
GW 8 11 0 -2.25 0 0 -2 7.66 0.04
GW 9 5 0 -2 7.66 0 2 7.66 0.04
GW 10 11 0 2 7.66 0 2.25 0 0.04
GW 11 7 0 2.25 0 0 7.35 0 0.04
GW 12 11 0 7.35 0 0 7.35 7.66 0.04
GW 13 7 0 7.35 7.66 0 2.45 7.66 0.04
GW 14 5 0 2.45 7.66 -0.1 2.1 4.8 0.04
GW 15 9 0 1.55 0 0 1.05 6.5 0.04
GW 16 9 0 1.05 6.5 0 1.05 0 0.04
GW 17 5 -0.1 -2.1 4.8 0 -2.45 7.66 0.04
GW 18 3 -0.1 2.1 4.8 0 1.55 0 0.04
GS 0 0 0.0254
GE 0
EK
LD 5 0 0 0 5.8e7 0
EX 0 1 2 0 1 0
GN -1
' FR Freq Sweep choices in order of increasing calculation time:
' FR 0 29 0 0 470 12 ' Freq Sweep 470-806 every 12 MHz
FR 0 39 0 0 470 6 ' Freq Sweep 470-698 every 6 MHz - PREFERRED FOR UHF
' FR 0 77 0 0 470 3 ' Freq Sweep 470-698 every 3 MHz
' FR 0 153 0 0 470 1.5 ' Freq Sweep 470-698 every 1.5 MHz
' RP choices in order of increasing calculation time:
' RP 0 1 1 1510 90 0 1 1 0 0 ' 1D Gain toward 90-deg Azimuth
' RP 0 1 37 1510 90 0 1 5 0 0 ' 2D (Left only) Azimuthal Gain Slice
RP 0 1 73 1510 90 0 1 5 0 0 ' 2D Azimuthal Gain Slice - PREFERRED
' RP 0 73 1 1510 90 0 5 1 0 0 ' 2D Elevation Gain Slice
' RP 0 73 73 1510 90 0 5 5 0 0 ' 3D Lower Hemisphere reveals antenna
' RP 0 145 73 1510 90 0 5 5 0 0 ' 3D Full Coverage obscures antenna
EN
I made fol. changes so L and R sides match up:
GW17 from 3 to 5, GW14 from 11 to 5 and GW18 from 3 to 6.
Autosegmenter gives significantly different results, depending on chosen segment number,
so I didn't go that route...
Since the Azimuthal pattern is max towards 240-deg at 174 MHz, 4nec2's Gain curve
is for that direction. The Gain towards 90-deg can be seen in the Azimuthal plot by
hitting the "J" key and navigate freq & azimuth via arrow keys. To PLOT the Gain curve
towards 90-deg, enable the FP statement below for "1D Gain" and comment out the
"2D Azimuthal Gain Slice" statement (a single quote mark, as shown below).
Gain is 3.0 dBi (174 MHz), rising to 8.5 dBi (566 MHz) and falling to 3.7 dBi (698 MHz).
But the SWR starts at 6, has a very narrow dip to 1.06 at 566 MHz and quickly jumps
to 22, so it's excessive over most of the UHF band, which can cause problems in many
situations, depending on cable length and other factors.
So, like many U-Tube wonders, it has some Raw Gain but is inherently defective....
Modified 4nec2 file:
CM Yet another U-Tube Defect, 4nec2 by Xauto, 24July2009
CM Segmentation corrected by holl_ands
CE
GW 1 3 0 -1.05 0 0 1.05 0 0.04
GW 2 9 0 -1.05 0 0 -1.05 6.5 0.04
GW 3 6 0 -1.05 6.5 0 -1.55 0 0.04
GW 4 6 0 -1.55 0 -0.1 -2.1 4.8 0.04
GW 5 6 0 -2.45 7.66 0 -7.35 7.66 0.04
GW 6 9 0 -7.35 7.66 0 -7.35 0 0.04
GW 7 7 0 -7.35 0 0 -2.25 0 0.04
GW 8 11 0 -2.25 0 0 -2 7.66 0.04
GW 9 5 0 -2 7.66 0 2 7.66 0.04
GW 10 11 0 2 7.66 0 2.25 0 0.04
GW 11 7 0 2.25 0 0 7.35 0 0.04
GW 12 11 0 7.35 0 0 7.35 7.66 0.04
GW 13 7 0 7.35 7.66 0 2.45 7.66 0.04
GW 14 5 0 2.45 7.66 -0.1 2.1 4.8 0.04
GW 15 9 0 1.55 0 0 1.05 6.5 0.04
GW 16 9 0 1.05 6.5 0 1.05 0 0.04
GW 17 5 -0.1 -2.1 4.8 0 -2.45 7.66 0.04
GW 18 3 -0.1 2.1 4.8 0 1.55 0 0.04
GS 0 0 0.0254
GE 0
EK
LD 5 0 0 0 5.8e7 0
EX 0 1 2 0 1 0
GN -1
' FR Freq Sweep choices in order of increasing calculation time:
' FR 0 29 0 0 470 12 ' Freq Sweep 470-806 every 12 MHz
FR 0 39 0 0 470 6 ' Freq Sweep 470-698 every 6 MHz - PREFERRED FOR UHF
' FR 0 77 0 0 470 3 ' Freq Sweep 470-698 every 3 MHz
' FR 0 153 0 0 470 1.5 ' Freq Sweep 470-698 every 1.5 MHz
' RP choices in order of increasing calculation time:
' RP 0 1 1 1510 90 0 1 1 0 0 ' 1D Gain toward 90-deg Azimuth
' RP 0 1 37 1510 90 0 1 5 0 0 ' 2D (Left only) Azimuthal Gain Slice
RP 0 1 73 1510 90 0 1 5 0 0 ' 2D Azimuthal Gain Slice - PREFERRED
' RP 0 73 1 1510 90 0 5 1 0 0 ' 2D Elevation Gain Slice
' RP 0 73 73 1510 90 0 5 5 0 0 ' 3D Lower Hemisphere reveals antenna
' RP 0 145 73 1510 90 0 5 5 0 0 ' 3D Full Coverage obscures antenna
EN
holl_ands: Thank you for the help. I still have not mastered 4nec2. I can get it to almost work 1/2 the time.
Edit:5:40AM 25 July. I look at this antenna again. It is small is size (7.7"X14.7") and if your Ch.s are from 23to37, it will work for you. This is not my first choice to use 8 feet of wire. If I had 8' of #12 I would make X-32 and get all (14-51) of the UHF.
Edit:5:40AM 25 July. I look at this antenna again. It is small is size (7.7"X14.7") and if your Ch.s are from 23to37, it will work for you. This is not my first choice to use 8 feet of wire. If I had 8' of #12 I would make X-32 and get all (14-51) of the UHF.
Like from here ? http://books.google.com/books?id=q1...-4zHBQ&sa=X&oi=book_result&ct=result&resnum=1Edit: It look very much like a "Joe Carr" Six Shooter.
Ive had a lot of old juke box style short wave/am/fm radios that had that box loop antenna in them, heh.
Rounding the corners in the example in post #220, to make a little easier build using pipes as a form, like this:
![]()
Produces this:
The vhf-hi gain shifts slightly to the higher channels.
The NEC file:
Produces this:
Code:
Net
Gain Channel
-4.7648 7
-1.0122 8
2.3001 9
4.8475 10
6.1502 11
6.2877 12
5.8249 13
6.0302 14
6.4712 15
6.8727 16
7.2152 17
7.5200 18
7.7790 19
8.0047 20
8.1998 21
8.3670 22
8.4993 23
8.6193 24
8.7098 25
8.7834 26
8.8424 27
8.8895 28
8.9078 29
8.9111 30
8.8757 31
8.7921 32
8.6345 33
8.4667 34
8.4436 35
8.5792 36
8.7411 37
8.8772 38
8.9841 39
9.0821 40
9.1707 41
9.2699 42
9.3805 43
9.5035 44
9.6410 45
9.7948 46
9.9670 47
10.1491 48
10.3308 49
10.5083 50
10.6510 51
10.7181 52The NEC file:
CM SBGH gen1 89mm feedpoint with Top Hat NAROD rounded corners
CE
GW 5 15 0 0 17.325 0 7.0587 17.325 0.05094488
GW 6 5 0 5.5569 16.2636614 0 7.0587 16.2636614 0.05094488
GW 7 3 0 7.3087008 17.075 0 7.3087008 16.5137 0.05094488
GW 8 1 0 5.3069016 16.0137 0 5.3069016 15.7486 0.05094488
GW 9 11 0 5.5569 15.4986205 0 10.9661929 15.4986221 0.05094488
GW 15 15 0 0 -17.325 0 7.0587 -17.325 0.05094488
GW 16 5 0 5.5569 -16.263661 0 7.0587 -16.263661 0.05094488
GW 17 3 0 7.3087008 -17.075 0 7.3087008 -16.514 0.05094488
GW 18 1 0 5.3069016 -16.014 0 5.3069016 -15.749 0.05094488
GW 19 11 0 5.5569 -15.499 0 10.9661929 -15.498622 0.05094488
GW 25 15 0 0 17.325 0 -7.0587 17.325 0.05094488
GW 26 5 0 -5.5569 16.2636614 0 -7.0587 16.2636614 0.05094488
GW 27 3 0 -7.3087008 17.075 0 -7.3087008 16.5137 0.05094488
GW 28 1 0 -5.3069016 16.0137 0 -5.3069016 15.7486 0.05094488
GW 29 11 0 -5.5569 15.4986221 0 -10.966193 15.4986221 0.05094488
GW 35 15 0 0 -17.325 0 -7.0587 -17.325 0.05094488
GW 36 5 0 -5.5569 -16.263661 0 -7.0587 -16.263661 0.05094488
GW 37 3 0 -7.3087008 -17.075 0 -7.3087008 -16.514 0.05094488
GW 38 1 0 -5.3069016 -16.014 0 -5.3069016 -15.749 0.05094488
GW 39 11 0 -5.5569 -15.498622 0 -10.966193 -15.498622 0.05094488
GW 30 15 0 1.73228346 0 0 6.73228346 5 0.05094856
GW 31 15 0 1.73228346 10 0 6.73228346 5 0.05094856
GW 32 15 0 1.73228346 10 0 6.73228346 15 0.05094856
GW 34 15 0 -1.7322835 0 0 -6.7322835 5 0.05094856
GW 35 15 0 -1.7322835 10 0 -6.7322835 5 0.05094856
GW 36 15 0 -1.7322835 10 0 -6.7322835 15 0.05094856
GW 38 15 0 1.73228346 0 0 6.73228346 -5 0.05094856
GW 39 15 0 1.73228346 -10 0 6.73228346 -5 0.05094856
GW 40 15 0 1.73228346 -10 0 6.73228346 -15 0.05094856
GW 42 15 0 -1.7322835 0 0 -6.7322835 -5 0.05094856
GW 43 15 0 -1.7322835 -10 0 -6.7322835 -5 0.05094856
GW 44 15 0 -1.7322835 -10 0 -6.7322835 -15 0.05094856
GW 103 13 0 6.73228346 15 0 12.3228346 15 0.05094856
GW 104 13 0 -6.7322835 15 0 -12.322835 15 0.05094856
GW 106 13 0 6.73228346 -15 0 12.3228346 -15 0.05094856
GW 107 13 0 -6.7322835 -15 0 -12.322835 -15 0.05094856
GW 146 3 0 -1.7322835 0 0 1.73228346 0 0.011
GW 147 1 0 -7.0587 17.325 0 -7.3087008 17.075 0.05094856
GW 148 1 0 -7.3087008 16.5137 0 -7.0587 16.2636614 0.05094856
GW 149 1 0 7.0587 17.325 0 7.3087008 17.075 0.05094856
GW 150 1 0 7.0587 16.2636614 0 7.3087008 16.5137 0.05094856
GW 151 1 0 -7.0587 -16.263661 0 -7.3087008 -16.514 0.05094856
GW 152 1 0 -7.3087008 -17.075 0 -7.0587 -17.325 0.05094856
GW 153 1 0 7.0587 -16.263661 0 7.3087008 -16.514 0.05094856
GW 154 1 0 7.3087008 -17.075 0 7.0587 -17.325 0.05094856
GW 155 1 0 -5.5569 16.2636614 0 -5.3069016 16.0137 0.05094856
GW 156 1 0 -5.3069016 15.7486 0 -5.5569 15.4986221 0.05094856
GW 157 1 0 5.5569 16.2636614 0 5.3069016 16.0137 0.05094856
GW 158 1 0 5.3069016 15.7486 0 5.5569 15.4986205 0.05094856
GW 159 1 0 -5.5569 -15.498622 0 -5.3069016 -15.749 0.05094856
GW 160 1 0 -5.5569 -16.263661 0 -5.3069016 -16.014 0.05094856
GW 161 1 0 5.5569 -15.499 0 5.3069016 -15.749 0.05094856
GW 162 1 0 5.3069016 -16.014 0 5.5569 -16.263661 0.05094856
GS 0 0 0.0254 ' All in in.
GE 0
EK
LD 5 0 0 0 5.8e7 0
EX 0 146 2 0 1 0
GN -1
FR 0 39 0 0 473 6
RP 0 1 73 1510 90. 0. 0. 20. 0. 0.
EN
I'm kind of surprised the GX card hasn't caught on more. Model files are so much easier to digest when you only have to deal with the upper quadrant.
For example, using a GX card a reflectorless SBGH can be brought down to just 5 GW cards (4 zigzags, plus the exicited element).
A SBGH with reflectors can be brought down to 8.
For example, using a GX card a reflectorless SBGH can be brought down to just 5 GW cards (4 zigzags, plus the exicited element).
Code:
GW 10 15 0 1.73228346 0 0 6.73228346 5 0.05094856
GW 11 15 0 1.73228346 10 0 6.73228346 5 0.05094856
GW 12 15 0 1.73228346 10 0 6.73228346 15 0.05094856
GW 13 13 0 6.73228346 15 0 12.3228346 15 0.05094856
GX 100 011
GW 901 3 0 -1.7322835 0 0 1.73228346 0 0.011
Code:
GW 10 15 0 1.73228346 0 0 6.73228346 5 0.05094856
GW 11 15 0 1.73228346 10 0 6.73228346 5 0.05094856
GW 12 15 0 1.73228346 10 0 6.73228346 15 0.05094856
GW 13 13 0 6.73228346 15 0 12.3228346 15 0.05094856
GW 50 25 -4.1338583 0.39370079 2.5 -4.1338583 12.0078740 2.5 0.1875
GW 51 25 -4.1338583 0.39370079 7.5 -4.1338583 12.4409449 7.5 0.1875
GW 52 25 -4.1338583 0.39370079 15 -4.1338583 12.4409449 15 0.1875
GX 100 011
GW 901 3 0 -1.7322835 0 0 1.73228346 0 0.011Yet another U-Tube Defect: One more correction.
AutoGainTest was way off. Reducing number of segments in GW1 helped, as well as a smaller radius:
GW 1 1 0 -1.05 0 0 1.05 0 0.007
Fewer segments in GW1 means the EX card also has to be changed:
EX 0 1 1 0 1 0
Results and 4nec2 file were posted here:
http://www.avsforum.com/avs-vb/showthread.php?p=16888175
AutoGainTest was way off. Reducing number of segments in GW1 helped, as well as a smaller radius:
GW 1 1 0 -1.05 0 0 1.05 0 0.007
Fewer segments in GW1 means the EX card also has to be changed:
EX 0 1 1 0 1 0
Results and 4nec2 file were posted here:
http://www.avsforum.com/avs-vb/showthread.php?p=16888175
holl_ands: Thanks for Not for TV. On that U-tube model, the slide show had no dimensions just a nail pattern and 8' of wire. So I eye-balled it. I was surprised that it ended up in the UHF band.
Heh, the Not Ready For Prime Time TV Antennas.Thanks for Not for TV
x-234
ok i wanted a nice 9 dbi for the VHF-HI with the SWR below 3 which i managed to do.
In the UHF the dbi is not that high 3 db more but i like the SWR for the 470 to 700 .
and yes i'm using 300ohms NARODs love them suckers
Need some help to bring up the dbi in the UHF 470 to 700 with out messing with my VHF -HI
ok i wanted a nice 9 dbi for the VHF-HI with the SWR below 3 which i managed to do.
In the UHF the dbi is not that high 3 db more but i like the SWR for the 470 to 700 .
and yes i'm using 300ohms NARODs love them suckers
Need some help to bring up the dbi in the UHF 470 to 700 with out messing with my VHF -HI
Code:
CM Oringnal SBGH design by John E. Davis
CM (wire Diam =7mm for array )
CM GHVHF-HI edit by WW
CE
GW 1 3 0 -2 0 0 1.2047244 0 0.11889764
GW 2 7 0 1.2047244 0 0 6.71653542 5.51181102 0.13779528
GW 3 7 0 6.71653542 5.51181102 0 1.2047244 11.023622 0.13779528
GW 4 7 0 1.2047244 11.023622 0 6.71653542 16.5354331 0.13779528
GW 5 5 0 6.71653542 16.5354331 0 10.9291339 16.5354331 0.13779528
GW 6 7 0 1.2047244 0 0 6.71653542 -5.511811 0.13779528
GW 7 7 0 6.71653542 -5.511811 0 1.2047244 -11.023622 0.13779528
GW 8 7 0 1.2047244 -11.023622 0 6.71653542 -16.535433 0.13779528
GW 9 5 0 6.71653542 -16.535433 0 10.9291339 -16.535433 0.13779528
GW 10 7 0 -2 0 0 -7.511811 5.51181102 0.13779528
GW 11 7 0 -7.511811 5.51181102 0 -2 11.023622 0.13779528
GW 12 7 0 -2 11.023622 0 -7.4952756 16.6 0.13779528
GW 13 5 0 -7.4952756 16.6 0 -11.795276 16.6 0.13779528
GW 14 7 0 -2 0 0 -7.511811 -5.511811 0.13779528
GW 15 7 0 -7.511811 -5.511811 0 -2 -11.023622 0.13779528
GW 16 7 0 -2 -11.023622 0 -7.511811 -16.535433 0.13779528
GW 17 5 0 -7.511811 -16.535433 0 -11.72441 -16.535433 0.13779528
GW 18 27 0 -15.5 17 0 15 17 0.16243037
GW 19 27 0 -17.5 -17 0 13 -17 0.16243037
GW 20 29 0 -16 37 0 16 37 0.16243037
GW 21 29 0 -17 -37 0 15 -37 0.16243037
GW 22 11 -4 -5.7952756 -1 -4 5.2047244 -1 0.16243037
GW 23 11 -4 -5.7952756 1 -4 5.2047244 1 0.16243037
GW 24 13 -4 -6.7952756 7 -4 6.2047244 7 0.16243037
GW 25 13 -4 -6.7952756 -7 -4 6.2047244 -7 0.16243037
GW 26 15 -4 -8.7952756 13 -4 7.2047244 13 0.16243037
GW 27 15 -4 -8.7952756 -13 -4 7.2047244 -13 0.16243037
GW 28 29 -16 -16 17 -16 16 17 0.16243037
GW 29 29 -16 -18 -17 -16 14 -17 0.16243037
GW 30 41 -16 -23 8 -16 23 8 0.16243037
GW 31 41 -16 -23 -8 -16 23 -8 0.16243037
GS 0 0 0.0254 ' All in in.
GE 0
EK
LD 5 0 0 0 2.49e7 0
EX 0 1 2 0 1 0
GN -1
FR 0 1 0 0 210 0wildwillie: Do you have two NAROD at each end (one @ 17" and one @ 37" [ this one out of the box])? Looks like a net gain of 8dBi on VHF-hi.
Xauto yes i have 4 NARODs
2 as you can see are 37 inches off from X Z+37 and Z-37
with 4 reflectors for VHF_HI back around 16 inches
I was going to test out putting 2 directors also
But i have a gut feeling that the UHF SWR will rise
2 as you can see are 37 inches off from X Z+37 and Z-37
with 4 reflectors for VHF_HI back around 16 inches
I was going to test out putting 2 directors also
But i have a gut feeling that the UHF SWR will rise
X-234 V2 added 4 directors For VHF_HI
and i brought the UHF reflectors in 1 inch
and i brought the UHF reflectors in 1 inch
Code:
CM Oringnal SBGH design by John E. Davis
CM (wire Diam =7mm for array )
CM GHVHF-HI edit by WW V2
CE
GW 1 3 0 -2 0 0 1.2047244 0 0.11889764
GW 2 7 0 1.2047244 0 0 6.71653542 5.51181102 0.13779528
GW 3 7 0 6.71653542 5.51181102 0 1.2047244 11.023622 0.13779528
GW 4 7 0 1.2047244 11.023622 0 6.71653542 16.5354331 0.13779528
GW 5 5 0 6.71653542 16.5354331 0 10.9291339 16.5354331 0.13779528
GW 6 7 0 1.2047244 0 0 6.71653542 -5.511811 0.13779528
GW 7 7 0 6.71653542 -5.511811 0 1.2047244 -11.023622 0.13779528
GW 8 7 0 1.2047244 -11.023622 0 6.71653542 -16.535433 0.13779528
GW 9 5 0 6.71653542 -16.535433 0 10.9291339 -16.535433 0.13779528
GW 10 7 0 -2 0 0 -7.511811 5.51181102 0.13779528
GW 11 7 0 -7.511811 5.51181102 0 -2 11.023622 0.13779528
GW 12 7 0 -2 11.023622 0 -7.4952756 16.6 0.13779528
GW 13 5 0 -7.4952756 16.6 0 -11.795276 16.6 0.13779528
GW 14 7 0 -2 0 0 -7.511811 -5.511811 0.13779528
GW 15 7 0 -7.511811 -5.511811 0 -2 -11.023622 0.13779528
GW 16 7 0 -2 -11.023622 0 -7.511811 -16.535433 0.13779528
GW 17 5 0 -7.511811 -16.535433 0 -11.72441 -16.535433 0.13779528
GW 18 27 0 -15.5 17 0 15 17 0.16243037
GW 19 27 0 -17.5 -17 0 13 -17 0.16243037
GW 20 29 0 -16 37 0 16 37 0.16243037
GW 21 29 0 -17 -37 0 15 -37 0.16243037
GW 22 11 -3 -5.7952756 -1 -3 5.2047244 -1 0.16243037
GW 23 11 -3 -5.7952756 1 -3 5.2047244 1 0.16243037
GW 24 13 -3 -6.7952756 7 -3 6.2047244 7 0.16243037
GW 25 13 -3 -6.7952756 -7 -3 6.2047244 -7 0.16243037
GW 26 15 -3 -8.7952756 13 -3 7.2047244 13 0.16243037
GW 27 15 -3 -8.7952756 -13 -3 7.2047244 -13 0.16243037
GW 28 29 -16 -16 17 -16 16 17 0.16243037
GW 29 29 -16 -18 -17 -16 14 -17 0.16243037
GW 30 41 -16 -23 8 -16 23 8 0.16243037
GW 31 41 -16 -23 -8 -16 23 -8 0.16243037
GW 32 21 4 -11 17 4 11 17 0.16243037
GW 33 21 4 -12 -17 4 10 -17 0.16243037
GW 34 17 8 -10 17 8 9 17 0.16243037
GW 35 17 8 -10 -17 8 9 -17 0.16243037
GS 0 0 0.0254 ' All in in.
GE 0
EK
LD 5 0 0 0 2.49e7 0
EX 0 1 2 0 1 0
GN -1
FR 0 1 0 0 210 0X-234 V3
UHF band 11 dbi
VHF_HI 7 to 13 8dbi and above SWR below 3
Xauto I brought everything back in to the box hehe
UHF band 11 dbi
VHF_HI 7 to 13 8dbi and above SWR below 3
Xauto I brought everything back in to the box hehe
Code:
CM Oringnal SBGH design by John E. Davis
CM (wire Diam =7mm for array )
CM GHVHF-HI V3 edit by WW SWR for all bands covered below 3
CE
GW 1 3 0 -2 0 0 1.2047244 0 0.11889764
GW 2 7 0 1.2047244 0 0 6.71653542 5.51181102 0.13779528
GW 3 7 0 6.71653542 5.51181102 0 1.2047244 11.023622 0.13779528
GW 4 7 0 1.2047244 11.023622 0 6.87432708 16.6957545 0.13779528
GW 5 5 0 6.87432708 16.6957545 0 12.0336681 16.6957545 0.13779528
GW 6 7 0 1.2047244 0 0 6.71653542 -5.511811 0.13779528
GW 7 7 0 6.71653542 -5.511811 0 1.2047244 -11.023622 0.13779528
GW 8 7 0 1.2047244 -11.023622 0 6.71653542 -16.535433 0.13779528
GW 9 5 0 6.71653542 -16.535433 0 11.8756205 -16.481135 0.13779528
GW 10 7 0 -2 0 0 -7.511811 5.51181102 0.13779528
GW 11 7 0 -7.511811 5.51181102 0 -2 11.023622 0.13779528
GW 12 7 0 -2 11.023622 0 -7.4952756 16.6 0.13779528
GW 13 5 0 -7.4952756 16.6 0 -12.654626 16.6 0.13779528
GW 14 7 0 -2 0 0 -7.511811 -5.511811 0.13779528
GW 15 7 0 -7.511811 -5.511811 0 -2 -11.023622 0.13779528
GW 16 7 0 -2 -11.023622 0 -7.511811 -16.535433 0.13779528
GW 17 5 0 -7.511811 -16.535433 0 -12.671161 -16.535433 0.13779528
GW 18 27 0 -15.5 17 0 15 17 0.16243037
GW 19 27 0 -17.5 -17 0 13 -17 0.16243037
GW 20 29 0 -18 24.3587167 0 15 24.3587167 0.16243037
GW 21 29 0 -18 -24.519037 0 15 -24.519037 0.16243037
GW 22 11 -3 -5.7952756 -1 -3 5.2047244 -1 0.16243037
GW 23 11 -3 -5.7952756 1 -3 5.2047244 1 0.16243037
GW 24 13 -3 -6.7952756 7 -3 6.2047244 7 0.16243037
GW 25 13 -3 -6.7952756 -7 -3 6.2047244 -7 0.16243037
GW 26 15 -3 -8.7952756 13 -3 7.2047244 13 0.16243037
GW 27 15 -3 -8.7952756 -13 -3 7.2047244 -13 0.16243037
GW 28 29 -13.948718 -16 17 -13.948718 16 17 0.16243037
GW 29 29 -13.948718 -18 -17 -13.948718 14 -17 0.16243037
GW 30 41 -13.948718 -23 8 -13.948718 23 8 0.16243037
GW 31 41 -13.948718 -23 -8 -13.948718 23 -8 0.16243037
GW 32 7 0 -4 21.3587167 0 3 21.3587167 0.16243037
GW 33 7 0 -4 -21.519037 0 3 -21.519037 0.16243037
GW 34 9 0 -6 22.3587167 0 4 22.3587167 0.16243037
GW 35 9 0 -6 -22.519037 0 4 -22.519037 0.16243037
GW 36 15 0 -9 23.3587167 0 8 23.3587167 0.16243037
GW 37 15 0 -9 -23.519037 0 8 -23.519037 0.16243037
GS 0 0 0.0254 ' All in in.
GE 0
EK
LD 5 0 0 0 2.49e7 0
EX 0 1 2 0 1 0
GN -1
FR 0 1 0 0 210 0I ran the above file using 4nec2 and found:
UHF Gain = 11.6 dBi (+/- 0.75 dB) for Ch14-51.
Hi-VHF Gain = 8.6 dBi (+/-0.4 dB) for Ch7-13.
SWR<3.0 for either UHF or Hi-VHF
Finally, a DBGH with excellent performance in both UHF and Hi-VHF Bands!!!!
However, in order for AutoGainTest=1.0 on Hi-VHF the SOURCE wire Radius must be changed:
UHF: 0.12 (or 0.11889764 if you like overkill....)
Hi-VHF: 0.08
=====================================
Notes re unequal segmentation on parallel wires might not be important,
but I did notice that 4nec2's AutoSegmenter could not get them go away.
FWIW, if you calculate the segment length for GW1 and compare to segment
length for other wires (esp. longer wires), more "equal" segmentation results
taking each wire length (use Geometry Editor) and divide by the segment length for GW1.
No, I didn't take the time to crank out the numbers for the entire file...
UHF Gain = 11.6 dBi (+/- 0.75 dB) for Ch14-51.
Hi-VHF Gain = 8.6 dBi (+/-0.4 dB) for Ch7-13.
SWR<3.0 for either UHF or Hi-VHF
Finally, a DBGH with excellent performance in both UHF and Hi-VHF Bands!!!!
However, in order for AutoGainTest=1.0 on Hi-VHF the SOURCE wire Radius must be changed:
UHF: 0.12 (or 0.11889764 if you like overkill....)
Hi-VHF: 0.08
=====================================
Notes re unequal segmentation on parallel wires might not be important,
but I did notice that 4nec2's AutoSegmenter could not get them go away.
FWIW, if you calculate the segment length for GW1 and compare to segment
length for other wires (esp. longer wires), more "equal" segmentation results
taking each wire length (use Geometry Editor) and divide by the segment length for GW1.
No, I didn't take the time to crank out the numbers for the entire file...
x-240
have a look gain is not to bad for VHF_HI
this is a copy of 300ohms DBGH no reflector 88mm feedgap
have a look gain is not to bad for VHF_HI
this is a copy of 300ohms DBGH no reflector 88mm feedgap
Code:
CM 300ohms DBGH no reflector
CM 88mm feedgap
CM 10 gauge phasing line with 2 inch phasing line gap, 1 inch high
CM VHF_HI edit by WW channel 7 needs to have SWR worked on
CE
GW 30 7 0 1.73228346 -17.635271 0 6.73228346 -12.635271 0.06424494
GW 31 7 0 1.73228346 -7.6352715 0 6.73228346 -12.635271 0.06424494
GW 32 7 0 1.73228346 -7.6352715 0 6.73228346 -2.6352715 0.06424494
GW 34 7 0 -1.7322835 -17.635271 0 -6.7322835 -12.635271 0.06424494
GW 35 7 0 -1.7322835 -7.6352715 0 -6.7322835 -12.635271 0.06424494
GW 36 7 0 -1.7322835 -7.6352715 0 -6.7322835 -2.6352715 0.06424494
GW 38 7 0 1.73228346 -17.635271 0 6.73228346 -22.635271 0.06424494
GW 39 7 0 1.73228346 -27.635271 0 6.73228346 -22.635271 0.06424494
GW 40 7 0 1.73228346 -27.635271 0 6.73228346 -32.635271 0.06424494
GW 42 7 0 -1.7322835 -17.635271 0 -6.7322835 -22.635271 0.06424494
GW 43 7 0 -1.7322835 -27.635271 0 -6.7322835 -22.635271 0.06424494
GW 44 7 0 -1.7322835 -27.635271 0 -6.7322835 -32.635271 0.06424494
GW 46 7 0 6.73228346 2.36472854 0 13.742954 2.36472854 0.06424494
GW 47 7 0 -6.7322835 2.36472854 0 -13.742953 2.36472854 0.06424494
GW 55 7 0 -6.7322835 2.36472854 0 -1.7322835 7.36472854 0.06424494
GW 56 7 0 6.73228346 2.36472854 0 1.73228346 7.36472854 0.06424494
GW 57 7 0 -6.7322835 32.3647285 0 -1.7322835 27.3647285 0.06424494
GW 58 7 0 6.73228346 32.3647285 0 1.73228346 27.3647285 0.06424494
GW 61 7 0 -1.7322835 7.36472854 0 -6.7322835 12.3647285 0.06424494
GW 62 7 0 1.73228346 7.36472854 0 6.73228346 12.3647285 0.06424494
GW 66 7 0 1.73228346 17.3647285 0 6.73228346 22.3647285 0.06424494
GW 67 7 0 -6.7322835 22.3647285 0 -1.7322835 27.3647285 0.06424494
GW 68 7 0 6.73228346 22.3647285 0 1.73228346 27.3647285 0.06424494
GW 69 7 0 1.73228346 17.3647285 0 6.73228346 12.3647285 0.06424494
GW 100 7 0 6.73228346 32.3647285 0 13.7429516 32.3647285 0.06424494
GW 101 7 0 -6.7322835 32.3647285 0 -13.742953 32.3647285 0.06424494
GW 103 7 0 6.73228346 -2.6352715 0 13.7429516 -2.6352715 0.06424494
GW 104 7 0 -6.7322835 -2.6352715 0 -13.742953 -2.4749508 0.06424494
GW 106 7 0 6.73228346 -32.635271 0 13.7429516 -32.635271 0.06424494
GW 107 7 0 -6.7322835 -32.635271 0 -13.742952 -32.474951 0.06424494
GW 121 1 0 -1.7322835 -17.635271 1 -1 -17.635271 0.0511811
GW 127 7 0 -6.7322835 22.3647285 0 -1.7322835 17.3647285 0.06424494
GW 128 7 0 -6.7322835 12.3647285 0 -1.7322835 17.3647285 0.06424494
GW 129 1 0 -1.7322835 17.3647285 1 -1 17.3647285 0.0511811
GW 110 1 0 1.73228346 -17.635271 1 1 -17.635271 0.0511811
GW 130 17 1 -1 17.3647285 1 -1 -0.1352715 0.0511811
GW 131 1 0 1.73228346 17.3647285 1 1 17.3647285 0.0511811
GW 132 17 1 1 17.3647285 1 1 -0.1352715 0.0511811
GW 133 17 1 -1 -0.1352715 1 -1 -17.635271 0.0511811
GW 134 17 1 1 -0.1352715 1 1 -17.635271 0.0511811
GW 135 3 1 -1 -0.1352715 1 1 -0.1352715 0.077
GW 136 27 0 -15.069034 33.0796592 0 15.4309661 33.0796592 0.077
GW 137 27 0 -15.47219 -33.408719 0 15.0278102 -33.408719 0.077
GW 138 27 0 -15.314397 1.51192224 0 15.1856033 1.51192224 0.077
GW 139 27 0 -15.156607 -1.9580168 0 15.3433929 -1.9580168 0.077
GW 140 31 0 -15 50 0 18.9989402 49.7315491 0.077
GW 141 31 0 -17.5 -50 0 16.5 -50 0.077
GW 142 27 0 -14.367652 -0.2014044 0 14.5297827 -0.2014044 0.077
GW 143 11 0 -5.6015776 12.4823646 0 5.44378719 12.4823646 0.077
GW 144 11 0 -5.4437866 -12.687976 0 5.60157825 -12.687976 0.077
GW 145 11 0 -5.4437866 22.5825644 0 5.44378719 22.5825644 0.077
GW 146 11 0 -5.6015776 -22.788176 0 5.60157825 -22.788176 0.077
GW 147 11 0 -5.6015776 32.2018036 0 5.60157825 32.2018036 0.077
GW 148 9 0 -5.2859955 -32.567735 0 4.97041463 -32.567735 0.16243037
GW 149 29 -9.94971 -15.70513 33.091182 -9.94971 16.794875 33.091182 0.1624304
GW 150 29 -9.94971 -16.34615 -33.81764 -9.94971 16.153847 -33.81764 0.1624304
GW 151 29 -10 -15.70513 29.5 -10 16.7948748 29.5 0.1624304
GW 152 29 -10.14497 -16.34615 -38.20742 -10.14497 16.153847 -38.20742 0.1624304
GW 153 29 -10.14497 -15.70513 35.939882 -10.14497 16.794875 35.939882 0.1624304
GW 154 29 -10 -16.34615 -30.170345 -10 16.1538469 -30.170345 0.1624304
GW 155 37 -10.14497 -20 0 -10.14497 20 0 0.1624304
GS 0 0 0.0254 ' All in in.
GE 0
EK
EX 0 135 2 0 1 0
GN -1
FR 0 1 0 0 210 0
RP 0 1 10 1510 90. 0. 0. 20. 0. 0.221 - 240 of 1328 Posts
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