Fractal TV Antenna Research & Development - Page 7 - Canadian TV, Computing and Home Theatre Forums

firimari · 2009-03-13, 02:01 PM

I took j3d's gapless GH10 and made the driven wires into first generation Koch Curves. (It should be noted for the pedants that the triangles should be equilateral, not right triangles like in the build photo above. Of course, right triangles might actually make for a better antenna...)
(6 AWG elements, 1/4 inch reflectors)

Code:

CM test output
CE
GW  1   7  0.000000 -0.035500  0.000000  0.000000  0.035500  0.000000  0.002058
GW  2   7  0.000000 -0.035500 -0.000000  0.000000 -0.089004 -0.053504  0.002058
GW  3   7  0.000000 -0.089004 -0.053504  0.000000 -0.162093 -0.033920  0.002058
GW  4   7  0.000000 -0.162093 -0.033920  0.000000 -0.142509 -0.107009  0.002058
GW  5   7  0.000000 -0.142509 -0.107009  0.000000 -0.196013 -0.160513  0.002058
GW  6   6  0.000000 -0.196013 -0.160513  0.000000 -0.150287 -0.206239  0.002058
GW  7   6  0.000000 -0.150287 -0.206239  0.000000 -0.167024 -0.268703  0.002058
GW  8   6  0.000000 -0.167024 -0.268703  0.000000 -0.104561 -0.251966  0.002058
GW  9   6  0.000000 -0.104561 -0.251966  0.000000 -0.058835 -0.297692  0.002058
GW 10   5  0.000000 -0.058835 -0.297692  0.000000 -0.100554 -0.339411  0.002058
GW 11   5  0.000000 -0.100554 -0.339411  0.000000 -0.157543 -0.324141  0.002058
GW 12   5  0.000000 -0.157543 -0.324141  0.000000 -0.142273 -0.381131  0.002058
GW 13   5  0.000000 -0.142273 -0.381131  0.000000 -0.183992 -0.422850  0.002058
GW 14  12  0.000000 -0.183992 -0.422850  0.000000 -0.307992 -0.422850  0.002058
GW 15   7  0.000000 -0.035500  0.000000  0.000000 -0.089004  0.053504  0.002058
GW 16   7  0.000000 -0.089004  0.053504  0.000000 -0.162093  0.033920  0.002058
GW 17   7  0.000000 -0.162093  0.033920  0.000000 -0.142509  0.107009  0.002058
GW 18   7  0.000000 -0.142509  0.107009  0.000000 -0.196013  0.160513  0.002058
GW 19   6  0.000000 -0.196013  0.160513  0.000000 -0.150287  0.206239  0.002058
GW 20   6  0.000000 -0.150287  0.206239  0.000000 -0.167024  0.268703  0.002058
GW 21   6  0.000000 -0.167024  0.268703  0.000000 -0.104561  0.251966  0.002058
GW 22   6  0.000000 -0.104561  0.251966  0.000000 -0.058835  0.297692  0.002058
GW 23   5  0.000000 -0.058835  0.297692  0.000000 -0.100554  0.339411  0.002058
GW 24   5  0.000000 -0.100554  0.339411  0.000000 -0.157543  0.324141  0.002058
GW 25   5  0.000000 -0.157543  0.324141  0.000000 -0.142273  0.381131  0.002058
GW 26   5  0.000000 -0.142273  0.381131  0.000000 -0.183992  0.422850  0.002058
GW 27  12  0.000000 -0.183992  0.422850  0.000000 -0.307992  0.422850  0.002058
GW 28   7  0.000000  0.035500 -0.000000  0.000000  0.089004 -0.053504  0.002058
GW 29   7  0.000000  0.089004 -0.053504  0.000000  0.162093 -0.033920  0.002058
GW 30   7  0.000000  0.162093 -0.033920  0.000000  0.142509 -0.107009  0.002058
GW 31   7  0.000000  0.142509 -0.107009  0.000000  0.196013 -0.160513  0.002058
GW 32   6  0.000000  0.196013 -0.160513  0.000000  0.150287 -0.206239  0.002058
GW 33   6  0.000000  0.150287 -0.206239  0.000000  0.167024 -0.268703  0.002058
GW 34   6  0.000000  0.167024 -0.268703  0.000000  0.104561 -0.251966  0.002058
GW 35   6  0.000000  0.104561 -0.251966  0.000000  0.058835 -0.297692  0.002058
GW 36   5  0.000000  0.058835 -0.297692  0.000000  0.100554 -0.339411  0.002058
GW 37   5  0.000000  0.100554 -0.339411  0.000000  0.157543 -0.324141  0.002058
GW 38   5  0.000000  0.157543 -0.324141  0.000000  0.142273 -0.381131  0.002058
GW 39   5  0.000000  0.142273 -0.381131  0.000000  0.183992 -0.422850  0.002058
GW 40  12  0.000000  0.183992 -0.422850  0.000000  0.307992 -0.422850  0.002058
GW 41   7  0.000000  0.035500  0.000000  0.000000  0.089004  0.053504  0.002058
GW 42   7  0.000000  0.089004  0.053504  0.000000  0.162093  0.033920  0.002058
GW 43   7  0.000000  0.162093  0.033920  0.000000  0.142509  0.107009  0.002058
GW 44   7  0.000000  0.142509  0.107009  0.000000  0.196013  0.160513  0.002058
GW 45   6  0.000000  0.196013  0.160513  0.000000  0.150287  0.206239  0.002058
GW 46   6  0.000000  0.150287  0.206239  0.000000  0.167024  0.268703  0.002058
GW 47   6  0.000000  0.167024  0.268703  0.000000  0.104561  0.251966  0.002058
GW 48   6  0.000000  0.104561  0.251966  0.000000  0.058835  0.297692  0.002058
GW 49   5  0.000000  0.058835  0.297692  0.000000  0.100554  0.339411  0.002058
GW 50   5  0.000000  0.100554  0.339411  0.000000  0.157543  0.324141  0.002058
GW 51   5  0.000000  0.157543  0.324141  0.000000  0.142273  0.381131  0.002058
GW 52   5  0.000000  0.142273  0.381131  0.000000  0.183992  0.422850  0.002058
GW 53  12  0.000000  0.183992  0.422850  0.000000  0.307992  0.422850  0.002058
GW 54  29 -0.081000 -0.147000 -0.073000 -0.081000  0.147000 -0.073000  0.003175
GW 55  29 -0.081000 -0.147000  0.073000 -0.081000  0.147000  0.073000  0.003175
GW 56  97 -0.081000 -0.489000 -0.196000 -0.081000  0.489000 -0.196000  0.003175
GW 57  97 -0.081000 -0.489000  0.196000 -0.081000  0.489000  0.196000  0.003175
GW 58  99 -0.081000 -0.496000 -0.307000 -0.081000  0.496000 -0.307000  0.003175
GW 59  99 -0.081000 -0.496000  0.307000 -0.081000  0.496000  0.307000  0.003175
GW 60  76 -0.081000 -0.382000 -0.418000 -0.081000  0.382000 -0.418000  0.003175
GW 61  76 -0.081000 -0.382000  0.418000 -0.081000  0.382000  0.418000  0.003175
GW 62 111 -0.081000 -0.557000 -0.539000 -0.081000  0.557000 -0.539000  0.003175
GW 63 111 -0.081000 -0.557000  0.539000 -0.081000  0.557000  0.539000  0.003175
GW 64  28 -0.081000 -0.143000 -0.681000 -0.081000  0.143000 -0.681000  0.003175
GW 65  28 -0.081000 -0.143000  0.681000 -0.081000  0.143000  0.681000  0.003175
GE 0
LD 5 0 0 0 2.49e+07
EK 0
FR 0 20 0 0 473 12
EX 0 1 4 0 1
GN -1 0 0 0 0.0 0.0  0.0  0.0  0.0  0.0
RP 0 1 61 1001 90 0 3 6 10000 0
EN

Performance wise, it drops off precipitously after 600 MHz.

Code:

#OUT: Forw-gain; Theta= 90; Phi= 0
#Freq [MHz]	Tot-gain [dBi]
        Fractal Reference
473	14.71   14.38
485	14.76   14.61
497	14.67   14.66
509	14.55   14.62
521	14.44   14.54
533	14.31   14.44
545	14.18   14.39
557	14.27   14.48
569	14.3    14.59
581	13.93   14.68
593	13.07   14.77
605	11.71   14.89
617	9.95    15.03
629	7.93    15.2
641	5.69    15.38
653	3.39    15.56
665	2.14    15.69
677	1.92    15.68
689	1.97    15.45
701	1.93    14.91

Xauto · 2009-03-13, 04:26 PM

firimari: "300ohm:" had a thread on fractals, so I knew that the gain curve would shift. Mine is a GH gen2 with 9" legs. I just like the looks. Thank you for the new info.

stampeder · 2009-03-22, 08:30 PM

This link was posted by SJ44 in the French forum today:

http://ruckman.net/blog/news.php?item.21.4

Xauto · 2009-03-22, 10:17 PM

I think 300ohm modeled this? If I remember it did not do all that well.

300ohm · 2009-03-22, 10:56 PM

Yeah, I modeled about that fractal bowtie. The bowties dont really take to fractalization as well as the GHs do. And like I said before, you lose some gain with fractalization, but you do get smaller size. Its a trade-off.

Walter Dnes · 2009-03-23, 09:28 PM

It occurs to me that as you add more and more pieces to the fractal, you eventually approach circular arcs. Here's what I mean. I just did the left-hand side, because it's bleeping hard to do a circular arc freehand with a trackball mouse

The other side should also be arcs. Is it even possible to model an "Arc-GH"?

300ohm · 2009-03-23, 10:40 PM

Quote:

The other side should also be arcs. Is it even possible to model an "Arc-GH"?

Yeah, its possible. But drawing it is a little tricky. It was on my to do list. But, after thinking about it, the arc is actually throwing less metal in the air to catch signals, so I wouldnt expect more gain.

firimari · 2009-04-22, 04:52 PM

The results of 4nec2's optimizer on a single-iteration of the Koch Curve for a one-diamond reflector-less GH. High SWR on the lower UHF channels, low gain on the higher ones, But from 518 MHz and higher SWR is under 4, and forward gain is between 8 and 10 for 470-668 MHz. Not bad for almost fitting in a half meter by half meter square.
The goal here is an indoor antenna that will fit behind a picture frame, for a relative that has reasonably decent signal strength. I'll probably try next making it a second iteration Koch Curve on at least the longer leg of the element.

Code:

CM Experimental Antenna Design X-008
CM Parameterized Reflectorless Single Diamond Grey Hoverman 
CM single iteration Koch Curve
CM UHF Antenna
CM AWG Gauge 12 Copper Wire
CE
SY gap=0.047743
SY segment_0_length=0.238629
SY segment_1_length=0.115095
SY tail_length=0.156403
SY wire_radius=1.0262e-03
SY sin045=0.707107
SY cos045=0.707107
SY sin075=0.965926
SY cos075=0.258819
SY sin135=0.707107
SY cos135=-0.707107
SY sin345=-0.258819
SY cos345=0.965926
SY s0_y0=gap-cos135*segment_0_length
SY s0_z0=0
SY s0_y1=s0_y0+0.333333*cos135*segment_0_length
SY s0_z1=s0_z0+0.333333*sin135*segment_0_length
SY s0_y2=s0_y1+0.333333*cos075*segment_0_length
SY s0_z2=s0_z1+0.333333*sin075*segment_0_length
SY s0_y3=s0_y0+0.666667*cos135*segment_0_length
SY s0_z3=s0_z0+0.666667*sin135*segment_0_length
SY s1_y0=gap
SY s1_z0=sin135*segment_0_length
SY s1_y1=s1_y0+0.333333*cos045*segment_1_length
SY s1_z1=s1_z0+0.333333*sin045*segment_1_length
SY s1_y2=s1_y1+0.333333*cos345*segment_1_length
SY s1_z2=s1_z1+0.333333*sin345*segment_1_length
SY s1_y3=s1_y0+0.666667*cos045*segment_1_length
SY s1_z3=s1_z0+0.666667*sin045*segment_1_length
SY tail_y0=gap+cos045*segment_1_length
SY tail_z0=sin135*segment_0_length+sin045*segment_1_length
SY tail_y1=gap+cos045*segment_1_length+tail_length
GW      1       17      0      -s0_y0    s0_z0   0       s0_y0    s0_z0   wire_radius
GW      2       3       0       s0_y0    s0_z0   0       s0_y1    s0_z1   wire_radius
GW      3       3       0       s0_y1    s0_z1   0       s0_y2    s0_z2   wire_radius
GW      4       3       0       s0_y2    s0_z2   0       s0_y3    s0_z3   wire_radius
GW      5       3       0       s0_y3    s0_z3   0       s1_y0    s1_z0   wire_radius
GW      6       3       0       s1_y0    s1_z0   0       s1_y1    s1_z1   wire_radius
GW      7       3       0       s1_y1    s1_z1   0       s1_y2    s1_z2   wire_radius
GW      8       3       0       s1_y2    s1_z2   0       s1_y3    s1_z3   wire_radius
GW      9       3       0       s1_y3    s1_z3   0     tail_y0  tail_z0   wire_radius
GW     10       3       0     tail_y0  tail_z0   0     tail_y1  tail_z0   wire_radius
GW     11       3       0      -s0_y0    s0_z0   0      -s0_y1    s0_z1   wire_radius
GW     12       3       0      -s0_y1    s0_z1   0      -s0_y2    s0_z2   wire_radius
GW     13       3       0      -s0_y2    s0_z2   0      -s0_y3    s0_z3   wire_radius
GW     14       3       0      -s0_y3    s0_z3   0      -s1_y0    s1_z0   wire_radius
GW     15       3       0      -s1_y0    s1_z0   0      -s1_y1    s1_z1   wire_radius
GW     16       3       0      -s1_y1    s1_z1   0      -s1_y2    s1_z2   wire_radius
GW     17       3       0      -s1_y2    s1_z2   0      -s1_y3    s1_z3   wire_radius
GW     18       3       0      -s1_y3    s1_z3   0    -tail_y0  tail_z0   wire_radius
GW     19       3       0    -tail_y0  tail_z0   0    -tail_y1  tail_z0   wire_radius
GW     20       3       0       s0_y0   -s0_z0   0       s0_y1   -s0_z1   wire_radius
GW     21       3       0       s0_y1   -s0_z1   0       s0_y2   -s0_z2   wire_radius
GW     22       3       0       s0_y2   -s0_z2   0       s0_y3   -s0_z3   wire_radius
GW     23       3       0       s0_y3   -s0_z3   0       s1_y0   -s1_z0   wire_radius
GW     24       3       0       s1_y0   -s1_z0   0       s1_y1   -s1_z1   wire_radius
GW     25       3       0       s1_y1   -s1_z1   0       s1_y2   -s1_z2   wire_radius
GW     26       3       0       s1_y2   -s1_z2   0       s1_y3   -s1_z3   wire_radius
GW     27       3       0       s1_y3   -s1_z3   0     tail_y0 -tail_z0   wire_radius
GW     28       3       0     tail_y0 -tail_z0   0     tail_y1 -tail_z0   wire_radius
GW     29       3       0      -s0_y0   -s0_z0   0      -s0_y1   -s0_z1   wire_radius
GW     30       3       0      -s0_y1   -s0_z1   0      -s0_y2   -s0_z2   wire_radius
GW     31       3       0      -s0_y2   -s0_z2   0      -s0_y3   -s0_z3   wire_radius
GW     32       3       0      -s0_y3   -s0_z3   0      -s1_y0   -s1_z0   wire_radius
GW     33       3       0      -s1_y0   -s1_z0   0      -s1_y1   -s1_z1   wire_radius
GW     34       3       0      -s1_y1   -s1_z1   0      -s1_y2   -s1_z2   wire_radius
GW     35       3       0      -s1_y2   -s1_z2   0      -s1_y3   -s1_z3   wire_radius
GW     36       3       0      -s1_y3   -s1_z3   0    -tail_y0 -tail_z0   wire_radius
GW     37       3       0    -tail_y0 -tail_z0   0    -tail_y1 -tail_z0   wire_radius
GE      0
LD      5       0       0       0       58000000
GN      -1
EK
EX      0       1       9      0       1.0
FR      0       38      0       0       470     6
RP      0       1       61      1001    90      0       3       6       10000   0
EN

300ohm · 2009-04-23, 04:07 AM

Quote:

making it a second iteration Koch Curve on at least the longer leg of the element.

firimari, thats a somewhat perfect example of what belongs in this thread, stuff thats cool (like my quad and octal GHs), yet probably shouldnt be built using techniques yet available to us. (I think I could build the above correctly, but wouldnt recommend others to do so)

firimari · 2009-04-23, 08:50 AM

Thanks for the compliment, 300ohm. Last night I was able to get the second iteration modelled, though I had to up the number of symbols that 4nec will evaluate. I could have spent a little more time simplifying my model to do that, but I just upped the max symbols to 128 instead. Anyway, close to the same results, but it looks prettier and is shorter (but not less wide)

Two lengths of 1468 mm long 12 gauge wire form the elements and the middle segment is 433mm long (which will get split in the middle for a 4:1 balun) Hopefully I can find time to build this soon.

Code:

CM Experimental Antenna Design X-010
CM Parameterized Reflectorless Single Diamond Grey Hoverman 
CM Second Iteration Koch Curve
CM UHF Antenna
CM AWG Gauge 12 Copper Wire
CE
SY gap=0.047743
SY segment_0_length=0.238629
SY segment_1_length=0.115095
SY tail_length=0.156403
SY wire_radius=1.0262e-03
SY sin015=0.258819
SY cos015=0.965926
SY sin045=0.707107
SY cos045=0.707107
SY sin075=0.965926
SY cos075=0.258819
SY sin135=0.707107
SY cos135=-0.707107
SY sin195=-0.258819
SY cos195=-0.965925
SY sin345=-0.258819
SY cos345=0.965926
SY s0_y00=gap-cos135*segment_0_length
SY s0_z00=0
SY s0_y01=s0_y00+0.111111*cos135*segment_0_length
SY s0_z01=s0_z00+0.111111*sin135*segment_0_length
SY s0_y02=s0_y01+0.111111*cos075*segment_0_length
SY s0_z02=s0_z01+0.111111*sin075*segment_0_length
SY s0_y03=s0_y00+0.222222*cos135*segment_0_length
SY s0_z03=s0_z00+0.222222*sin135*segment_0_length
SY s0_y04=s0_y00+0.333333*cos135*segment_0_length
SY s0_z04=s0_z00+0.333333*sin135*segment_0_length
SY s0_y05=s0_y04+0.111111*cos075*segment_0_length
SY s0_z05=s0_z04+0.111111*sin075*segment_0_length
SY s0_y06=s0_y05+0.111111*cos015*segment_0_length
SY s0_z06=s0_z05+0.111111*sin015*segment_0_length
SY s0_y07=s0_y04+0.222222*cos075*segment_0_length
SY s0_z07=s0_z04+0.222222*sin075*segment_0_length
SY s0_y08=s0_y04+0.333333*cos075*segment_0_length
SY s0_z08=s0_z04+0.333333*sin075*segment_0_length
SY s0_y09=s0_y08+0.111111*cos195*segment_0_length
SY s0_z09=s0_z08+0.111111*sin195*segment_0_length
SY s0_y10=s0_y09+0.111111*cos135*segment_0_length
SY s0_z10=s0_z09+0.111111*sin135*segment_0_length
SY s0_y11=s0_y08+0.222222*cos195*segment_0_length
SY s0_z11=s0_z08+0.222222*sin195*segment_0_length
SY s0_y12=s0_y00+0.666667*cos135*segment_0_length
SY s0_z12=s0_z00+0.666667*sin135*segment_0_length
SY s0_y13=s0_y00+0.777778*cos135*segment_0_length
SY s0_z13=s0_z00+0.777778*sin135*segment_0_length
SY s0_y14=s0_y13+0.111111*cos075*segment_0_length
SY s0_z14=s0_z13+0.111111*sin075*segment_0_length
SY s0_y15=s0_y00+0.888889*cos135*segment_0_length
SY s0_z15=s0_z00+0.888889*sin135*segment_0_length
SY s1_y0=gap
SY s1_z0=sin135*segment_0_length
SY s1_y1=s1_y0+0.333333*cos045*segment_1_length
SY s1_z1=s1_z0+0.333333*sin045*segment_1_length
SY s1_y2=s1_y1+0.333333*cos345*segment_1_length
SY s1_z2=s1_z1+0.333333*sin345*segment_1_length
SY s1_y3=s1_y0+0.666667*cos045*segment_1_length
SY s1_z3=s1_z0+0.666667*sin045*segment_1_length
SY tail_y0=gap+cos045*segment_1_length
SY tail_z0=sin135*segment_0_length+sin045*segment_1_length
SY tail_y1=gap+cos045*segment_1_length+tail_length
GW      1       17      0     -s0_y00   s0_z00   0      s0_y00   s0_z00   wire_radius
GW      2       3       0      s0_y00   s0_z00   0      s0_y01   s0_z01   wire_radius
GW      3       3       0      s0_y01   s0_z01   0      s0_y02   s0_z02   wire_radius
GW      4       3       0      s0_y02   s0_z02   0      s0_y03   s0_z03   wire_radius
GW      5       3       0      s0_y03   s0_z03   0      s0_y04   s0_z04   wire_radius
GW      6       3       0      s0_y04   s0_z04   0      s0_y05   s0_z05   wire_radius
GW      7       3       0      s0_y05   s0_z05   0      s0_y06   s0_z06   wire_radius
GW      8       3       0      s0_y06   s0_z06   0      s0_y07   s0_z07   wire_radius
GW      9       3       0      s0_y07   s0_z07   0      s0_y08   s0_z08   wire_radius
GW     10       3       0      s0_y08   s0_z08   0      s0_y09   s0_z09   wire_radius
GW     11       3       0      s0_y09   s0_z09   0      s0_y10   s0_z10   wire_radius
GW     12       3       0      s0_y10   s0_z10   0      s0_y11   s0_z11   wire_radius
GW     13       3       0      s0_y11   s0_z11   0      s0_y12   s0_z12   wire_radius
GW     14       3       0      s0_y12   s0_z12   0      s0_y13   s0_z13   wire_radius
GW     15       3       0      s0_y13   s0_z13   0      s0_y14   s0_z14   wire_radius
GW     16       3       0      s0_y14   s0_z14   0      s0_y15   s0_z15   wire_radius
GW     17       3       0      s0_y15   s0_z15   0       s1_y0    s1_z0   wire_radius
GW     18       3       0       s1_y0    s1_z0   0       s1_y1    s1_z1   wire_radius
GW     19       3       0       s1_y1    s1_z1   0       s1_y2    s1_z2   wire_radius
GW     20       3       0       s1_y2    s1_z2   0       s1_y3    s1_z3   wire_radius
GW     21       3       0       s1_y3    s1_z3   0     tail_y0  tail_z0   wire_radius
GW     22       3       0     tail_y0  tail_z0   0     tail_y1  tail_z0   wire_radius
GW     23       3       0     -s0_y00   s0_z00   0     -s0_y01   s0_z01   wire_radius
GW     24       3       0     -s0_y01   s0_z01   0     -s0_y02   s0_z02   wire_radius
GW     25       3       0     -s0_y02   s0_z02   0     -s0_y03   s0_z03   wire_radius
GW     26       3       0     -s0_y03   s0_z03   0     -s0_y04   s0_z04   wire_radius
GW     27       3       0     -s0_y04   s0_z04   0     -s0_y05   s0_z05   wire_radius
GW     28       3       0     -s0_y05   s0_z05   0     -s0_y06   s0_z06   wire_radius
GW     29       3       0     -s0_y06   s0_z06   0     -s0_y07   s0_z07   wire_radius
GW     30       3       0     -s0_y07   s0_z07   0     -s0_y08   s0_z08   wire_radius
GW     31       3       0     -s0_y08   s0_z08   0     -s0_y09   s0_z09   wire_radius
GW     32       3       0     -s0_y09   s0_z09   0     -s0_y10   s0_z10   wire_radius
GW     33       3       0     -s0_y10   s0_z10   0     -s0_y11   s0_z11   wire_radius
GW     34       3       0     -s0_y11   s0_z11   0     -s0_y12   s0_z12   wire_radius
GW     35       3       0     -s0_y12   s0_z12   0     -s0_y13   s0_z13   wire_radius
GW     36       3       0     -s0_y13   s0_z13   0     -s0_y14   s0_z14   wire_radius
GW     37       3       0     -s0_y14   s0_z14   0     -s0_y15   s0_z15   wire_radius
GW     38       3       0     -s0_y15   s0_z15   0      -s1_y0    s1_z0   wire_radius
GW     39       3       0      -s1_y0    s1_z0   0      -s1_y1    s1_z1   wire_radius
GW     40       3       0      -s1_y1    s1_z1   0      -s1_y2    s1_z2   wire_radius
GW     41       3       0      -s1_y2    s1_z2   0      -s1_y3    s1_z3   wire_radius
GW     42       3       0      -s1_y3    s1_z3   0    -tail_y0  tail_z0   wire_radius
GW     43       3       0    -tail_y0  tail_z0   0    -tail_y1  tail_z0   wire_radius
GW     44       3       0     -s0_y00  -s0_z00   0     -s0_y01  -s0_z01   wire_radius
GW     45       3       0     -s0_y01  -s0_z01   0     -s0_y02  -s0_z02   wire_radius
GW     46       3       0     -s0_y02  -s0_z02   0     -s0_y03  -s0_z03   wire_radius
GW     47       3       0     -s0_y03  -s0_z03   0     -s0_y04  -s0_z04   wire_radius
GW     48       3       0     -s0_y04  -s0_z04   0     -s0_y05  -s0_z05   wire_radius
GW     49       3       0     -s0_y05  -s0_z05   0     -s0_y06  -s0_z06   wire_radius
GW     50       3       0     -s0_y06  -s0_z06   0     -s0_y07  -s0_z07   wire_radius
GW     51       3       0     -s0_y07  -s0_z07   0     -s0_y08  -s0_z08   wire_radius
GW     52       3       0     -s0_y08  -s0_z08   0     -s0_y09  -s0_z09   wire_radius
GW     53       3       0     -s0_y09  -s0_z09   0     -s0_y10  -s0_z10   wire_radius
GW     54       3       0     -s0_y10  -s0_z10   0     -s0_y11  -s0_z11   wire_radius
GW     55       3       0     -s0_y11  -s0_z11   0     -s0_y12  -s0_z12   wire_radius
GW     56       3       0     -s0_y12  -s0_z12   0     -s0_y13  -s0_z13   wire_radius
GW     57       3       0     -s0_y13  -s0_z13   0     -s0_y14  -s0_z14   wire_radius
GW     58       3       0     -s0_y14  -s0_z14   0     -s0_y15  -s0_z15   wire_radius
GW     59       3       0     -s0_y15  -s0_z15   0      -s1_y0   -s1_z0   wire_radius
GW     60       3       0      -s1_y0   -s1_z0   0      -s1_y1   -s1_z1   wire_radius
GW     61       3       0      -s1_y1   -s1_z1   0      -s1_y2   -s1_z2   wire_radius
GW     62       3       0      -s1_y2   -s1_z2   0      -s1_y3   -s1_z3   wire_radius
GW     63       3       0      -s1_y3   -s1_z3   0    -tail_y0 -tail_z0   wire_radius
GW     64       3       0    -tail_y0 -tail_z0   0    -tail_y1 -tail_z0   wire_radius
GW     65       3       0      s0_y00  -s0_z00   0      s0_y01  -s0_z01   wire_radius
GW     66       3       0      s0_y01  -s0_z01   0      s0_y02  -s0_z02   wire_radius
GW     67       3       0      s0_y02  -s0_z02   0      s0_y03  -s0_z03   wire_radius
GW     68       3       0      s0_y03  -s0_z03   0      s0_y04  -s0_z04   wire_radius
GW     69       3       0      s0_y04  -s0_z04   0      s0_y05  -s0_z05   wire_radius
GW     70       3       0      s0_y05  -s0_z05   0      s0_y06  -s0_z06   wire_radius
GW     71       3       0      s0_y06  -s0_z06   0      s0_y07  -s0_z07   wire_radius
GW     72       3       0      s0_y07  -s0_z07   0      s0_y08  -s0_z08   wire_radius
GW     73       3       0      s0_y08  -s0_z08   0      s0_y09  -s0_z09   wire_radius
GW     74       3       0      s0_y09  -s0_z09   0      s0_y10  -s0_z10   wire_radius
GW     75       3       0      s0_y10  -s0_z10   0      s0_y11  -s0_z11   wire_radius
GW     76       3       0      s0_y11  -s0_z11   0      s0_y12  -s0_z12   wire_radius
GW     77       3       0      s0_y12  -s0_z12   0      s0_y13  -s0_z13   wire_radius
GW     78       3       0      s0_y13  -s0_z13   0      s0_y14  -s0_z14   wire_radius
GW     79       3       0      s0_y14  -s0_z14   0      s0_y15  -s0_z15   wire_radius
GW     80       3       0      s0_y15  -s0_z15   0       s1_y0   -s1_z0   wire_radius
GW     81       3       0       s1_y0   -s1_z0   0       s1_y1   -s1_z1   wire_radius
GW     82       3       0       s1_y1   -s1_z1   0       s1_y2   -s1_z2   wire_radius
GW     83       3       0       s1_y2   -s1_z2   0       s1_y3   -s1_z3   wire_radius
GW     84       3       0       s1_y3   -s1_z3   0     tail_y0 -tail_z0   wire_radius
GW     85       3       0     tail_y0 -tail_z0   0     tail_y1 -tail_z0   wire_radius
GE      0
LD      5       0       0       0       58000000
GN      -1
EK
EX      0       1       9      0       1.0
FR      0       38      0       0       470     6
RP      0       1       61      1001    90      0       3       6       10000   0
EN

sh48 · 2009-06-26, 12:48 AM

Hey! Great forum. Here is my 2cents.

Good news is I live on a hill, not so good is the high rise blocking about 100 degrees of the view south. But yet I receive most of the Toronto and Buffalo DT stations using an indoor fractal antenna. It is constructed with 20ga wire, finishing nails, and hidden inside an old cassette storage box. A 9" cake rack fits inside the box as a reflector or resonator... whatever.

The low-noise preamps at Sayal were sold out so I tried a cheap 10db RCA indoor preamp from Home Depot. Perhaps it makes a slight improvement but I am not sure.

Slight pixelation occurs sometimes on 44.1 and 29.1 which I believe can be solved by antenna improvements.. 29 only works at a very specific location in the TV room.

Hacking is mostly effective but leaves unanswered questions. Does anyone know how to model or engineer a fractal antenna.?

stampeder · 2009-06-26, 01:59 AM

Which fractal antenna design did you use? Most readers do not know what a fractal antenna is, so please give specifics.

20ga wire sure is thin for an antenna.

300ohm · 2009-06-26, 07:53 AM

Quote:

Does anyone know how to model or engineer a fractal antenna.?

There are a few fractal GH's and bowtie modeled on this forum.

sh48 · 2009-06-27, 01:05 AM

Quote:

Originally Posted by stampeder

Which fractal antenna design did you use? Most readers do not know what a fractal antenna is, so please give specifics.

20ga wire sure is thin for an antenna.

Hi: I was inspired by Mr. Ruckman's page on instructables.com. He explains a little about fractals. Yes, the wire is thin but I don't know what size it should be.

sh48 · 2009-06-27, 01:08 AM

Quote:

Originally Posted by 300ohm

There are a few fractal GH's and bowtie modeled on this forum.

Hi: I reallly like the Gray-Hoverman.. but I have no place to put it.

2009-03-22, 08:30 PM	#93
stampeder OTA Forum Moderator Join Date: Jan 2005 Location: North Delta, BC (96Av x 116St) Posts: 23,338	Fractal antenna site This link was posted by SJ44 in the French forum today: http://ruckman.net/blog/news.php?item.21.4

2009-03-22, 10:56 PM	#95
300ohm Veteran Join Date: Mar 2008 Location: Somewhere in Delaware on the flat side Posts: 7,011	Yeah, I modeled about that fractal bowtie. The bowties dont really take to fractalization as well as the GHs do. And like I said before, you lose some gain with fractalization, but you do get smaller size. Its a trade-off. __________________ My builds/plans (not the latest models) are located here.

2009-06-26, 12:48 AM	#101
sh48 Rookie Join Date: Jun 2009 Location: Richmond Hill, Ont Posts: 21	Fractal Antenna Results Hey! Great forum. Here is my 2cents. Good news is I live on a hill, not so good is the high rise blocking about 100 degrees of the view south. But yet I receive most of the Toronto and Buffalo DT stations using an indoor fractal antenna. It is constructed with 20ga wire, finishing nails, and hidden inside an old cassette storage box. A 9" cake rack fits inside the box as a reflector or resonator... whatever. The low-noise preamps at Sayal were sold out so I tried a cheap 10db RCA indoor preamp from Home Depot. Perhaps it makes a slight improvement but I am not sure. Slight pixelation occurs sometimes on 44.1 and 29.1 which I believe can be solved by antenna improvements.. 29 only works at a very specific location in the TV room. Hacking is mostly effective but leaves unanswered questions. Does anyone know how to model or engineer a fractal antenna.?

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2009-03-13, 04:26 PM	#92
Xauto Join Date: Sep 2008 Posts: 487	firimari: "300ohm:" had a thread on fractals, so I knew that the gain curve would shift. Mine is a GH gen2 with 9" legs. I just like the looks. Thank you for the new info.

2009-03-22, 10:17 PM	#94
Xauto Join Date: Sep 2008 Posts: 487	I think 300ohm modeled this? If I remember it did not do all that well.

2009-06-26, 01:59 AM	#102
stampeder OTA Forum Moderator Join Date: Jan 2005 Location: North Delta, BC (96Av x 116St) Posts: 23,338	Which fractal antenna design did you use? Most readers do not know what a fractal antenna is, so please give specifics. 20ga wire sure is thin for an antenna.