Ch2-69 + FM Band Circular Crossed Loops were analyzed using 4nec2. For the purpose of this analysis, Dimensions for the OMNI UVOX-2 were assumed, per info on their website: http://www.omnitenna.com
Not knowing the particulars of the internal design, TWO versions are analyzed here:
====================================== a) Feedpoint Gaps at bottoms of both Loops are Directly Interconnected using short wires. Azimuthal Pattern is BI-DIRECTIONAL across ALL Frequency Bands for BOTH Horizontal and RHCP (Right-hand Circular Polarization).
Direct Connect using Short Wires between the Loop Feedpoints MAX Gain for Horizontal and Right-Hand Circular Polarization (RHCP): Lo-VHF: -1.6 dBi, -0.9 dBc FM: -0.3 dBi, -0.8 dBc Hi-VHF: 2.7 dBi, -0.2 dBc UHF: 2.6 dBi, 1.9 dBc
====================================== b) A Transmission Line (located within the support structure) Interconnects both Loops. TL Length chosen for Max Gain and Minimum Null Depth for Horizontal or RHCP. Azimuthal Pattern is BI-DIRECTIONAL across ALL Frequency Bands for BOTH Horizontal and RHCP (Right-hand Circular Polarization), except at highest Frequencies degenerates to a FOUR-LOBE Pattern. Note Max Gain Axis Rotation across Hi-VHF Band, so Max Gain in Lo-VHF Band aligns with NULLs in other Bands.
Transmission Line Interconnection Between the Loop Feedpoints: MAX Gain for Horizontal and Right-Hand Circular Polarization (RHCP): Lo-VHF: -1.6 dBi, -0.9 dBc FM: -0.3 dBi, -0.8 dBc Hi-VHF: 2.4 dBi, -0.1 dBc UHF: 4.3 dBi, 1.8 dBc
Note that Max Gain Performance in each Band is essentially IDENTICAL for Both Alternatives.
23 Aug 201578 items3800 visitsAlbum by holl_ands
enlarge 93KB, 1015x1024 1 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires 3D View
enlarge 296KB, 1024x886 2 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Front View [1 large square = 1.25 inches]
enlarge 279KB, 1024x886 3 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Top View [1 large square = 1.25 inches]
enlarge 44KB, 1024x886 4 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires 3D View DETAIL
enlarge 37KB, 791x1024 5 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires 4nec2 File Contains Summary of Dimensions
enlarge 117KB, 1152x476 6 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 Total Raw Gain "Forward" (90-deg Azimuth) [UPPER Limit for Horiz. & RHCP Gain]
enlarge 115KB, 1152x476 7 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 Total Raw Gain on "Diagonal" (45-deg Azimuth) [UPPER Limit for Horiz. & RHCP Gain]
enlarge 117KB, 1152x476 8 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 Total Raw Gain to "Side" (0-deg Azimuth) [UPPER Limit for Horiz. & RHCP Gain]
enlarge 109KB, 1152x476 9 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 Total Raw Gain "Diagonal" (315-deg Azimuth) [UPPER Limit for Horiz. & RHCP Gain]
enlarge 200KB, 1024x722 10 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 SWR (300-ohms) is HIGH, esp. in VHF Band
enlarge 216KB, 1024x722 11 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 SWR (75-ohms) is WORSE
enlarge 261KB, 1024x722 12 Ch2-69 Crossed Loops Direct Connect with 2 Short Wires Ch2-69 Impedance
enlarge 310KB, 1024x1024 13 Ch2-69 Crossed Loops - 54 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 310KB, 1024x1024 14 Ch2-69 Crossed Loops - 66 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 310KB, 1024x1024 15 Ch2-69 Crossed Loops - 78 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 309KB, 1024x1024 16 Ch2-69 Crossed Loops - 174 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 307KB, 1024x1024 17 Ch2-69 Crossed Loops - 198 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 305KB, 1024x1024 18 Ch2-69 Crossed Loops - 216 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 326KB, 1024x1024 19 Ch2-69 Crossed Loops - 470 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 320KB, 1024x1024 20 Ch2-69 Crossed Loops - 530 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 321KB, 1024x1024 21 Ch2-69 Crossed Loops - 590 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 320KB, 1024x1024 22 Ch2-69 Crossed Loops - 650 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 315KB, 1024x1024 23 Ch2-69 Crossed Loops - 698 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 327KB, 1024x1024 24 Ch2-69 Crossed Loops - 806 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Diagonal NULLs in Horizontal Gain
enlarge 324KB, 1024x1024 25 Ch2-69 Crossed Loops - 54 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 324KB, 1024x1024 26 Ch2-69 Crossed Loops - 66 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 27 Ch2-69 Crossed Loops - 88 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 28 Ch2-69 Crossed Loops - 88 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 320KB, 1024x1024 29 Ch2-69 Crossed Loops - 98 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 30 Ch2-69 Crossed Loops - 108 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 333KB, 1024x1024 31 Ch2-69 Crossed Loops - 470 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: Bi-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 325KB, 1024x1024 32 Ch2-69 Crossed Loops - 530 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: Bi-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 317KB, 1024x1024 33 Ch2-69 Crossed Loops - 590 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: Bi-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 319KB, 1024x1024 34 Ch2-69 Crossed Loops - 650 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: FOUR-LOBED Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 319KB, 1024x1024 35 Ch2-69 Crossed Loops - 698 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: Bi-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 325KB, 1024x1024 36 Ch2-69 Crossed Loops - 806 MHz Direct Connect with 2 Short Wires Azimuthal Pattern: Bi-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 93KB, 987x1024 37 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops 3D View
enlarge 292KB, 1024x886 38 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Front View [1 large square = 1.25 inches]
enlarge 280KB, 1024x886 39 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Top View [1 large square = 1.25 inches]
enlarge 295KB, 1024x886 40 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Side View [1 large square = 1.25 inches]
enlarge 36KB, 791x1024 41 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops 4nec2 File Includes Summary of Dimensions
enlarge 129KB, 1152x426 42 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 Total Raw Gain "Forward" (90-deg Azimuth)
enlarge 116KB, 1152x424 43 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 Total Raw Gain on "Diagonal" (45-deg Azimuth)
enlarge 122KB, 1152x426 44 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 Total Raw Gain to "Side" (0-deg Azimuth)
enlarge 123KB, 1152x480 45 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 Total Raw Gain on "Diagonal" (315-deg Azimuth)
enlarge 219KB, 1024x747 46 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 SWR (300-ohms) is HIGH, esp. in VHF Band
enlarge 211KB, 1024x747 47 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 SWR (75-ohms) is WORSE
enlarge 231KB, 1024x747 48 Ch2-69 Crossed Loops Transmission Line Length = 0.26-meters Interconnects the Two Loops Ch2-69 Impedance
enlarge 325KB, 1024x1024 49 Ch2-69 Crossed Loops - 54 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 324KB, 1024x1024 50 Ch2-69 Crossed Loops - 66 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 323KB, 1024x1024 51 Ch2-69 Crossed Loops - 78 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 321KB, 1024x1024 52 Ch2-69 Crossed Loops - 88 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 321KB, 1024x1024 53 Ch2-69 Crossed Loops - 98 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 325KB, 1024x1024 54 Ch2-69 Crossed Loops - 108 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep Diagonal NULLs
enlarge 315KB, 1024x1024 55 Ch2-69 Crossed Loops - 174 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep NULLs Note Hi-VHF Max Gain is Offset 45-deg from Lo-VHF + FM
enlarge 311KB, 1024x1024 56 Ch2-69 Crossed Loops - 198 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Note Hi-VHF Max Gain almost aligns with Lo-VHF + FM Max Gain
enlarge 309KB, 1024x1024 57 Ch2-69 Crossed Loops - 216 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep NULLs Note Hi-VHF Max Gain almost aligns with Lo-VHF + FM Max Gain
enlarge 339KB, 1024x1024 58 Ch2-69 Crossed Loops - 470 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has moderate NULLs Note Hi-VHF Max Gain aligns with Lo-VHF + FM NULLs
enlarge 320KB, 1024x1024 59 Ch2-69 Crossed Loops - 530 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has NULLs Note Hi-VHF Max Gain aligns with Lo-VHF + FM NULLs
enlarge 321KB, 1024x1024 60 Ch2-69 Crossed Loops - 590 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Horizontal Gain has deep NULLs Note Hi-VHF Max Gain aligns with Lo-VHF + FM NULLs
enlarge 315KB, 1024x1024 61 Ch2-69 Crossed Loops - 650 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: SIX-LOBES Horizontal Gain has deep NULLs
enlarge 314KB, 1024x1024 62 Ch2-69 Crossed Loops - 698 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: FOUR-LOBES Horizontal Gain has deep NULLs Note Max Gain is Offset 45-deg from Lo-VHF + FM
enlarge 322KB, 1024x1024 63 Ch2-69 Crossed Loops - 806 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: FOUR-LOBES Horizontal Gain has moderate NULLs Note Max Gain is Offset 45-deg from Lo-VHF + FM
enlarge 327KB, 1024x1024 64 Ch2-69 Crossed Loops - 650 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 324KB, 1024x1024 65 Ch2-69 Crossed Loops - 66 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 66 Ch2-69 Crossed Loops - 78 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 67 Ch2-69 Crossed Loops - 88 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 320KB, 1024x1024 68 Ch2-69 Crossed Loops - 98 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 69 Ch2-69 Crossed Loops - 108 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 70 Ch2-69 Crossed Loops - 174 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 324KB, 1024x1024 71 Ch2-69 Crossed Loops - 198 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 323KB, 1024x1024 72 Ch2-69 Crossed Loops - 216 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in the Nulls for RHCP (Right-Hand Circular Polarization)
enlarge 335KB, 1024x1024 73 Ch2-69 Crossed Loops - 470 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in NULLs for RHCP Note UHF Max Gain Diagonal aligns with MINIMUM in Hi-VHF Band
enlarge 325KB, 1024x1024 74 Ch2-69 Crossed Loops - 530 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in NULLs for RHCP Note UHF Max Gain Diagonal aligns with MINIMUM in Hi-VHF Band
enlarge 318KB, 1024x1024 75 Ch2-69 Crossed Loops - 590 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: BI-DIRECTIONAL Significant Loss in NULLs for RHCP Note UHF Max Gain Diagonal aligns with MINIMUM in Hi-VHF Band
enlarge 317KB, 1024x1024 76 Ch2-69 Crossed Loops - 650 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: FOUR-LOBES Significant Loss in NULLs for RHCP
enlarge 323KB, 1024x1024 77 Ch2-69 Crossed Loops - 698 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: FOUR-LOBES Significant Loss in NULLs for RHCP
enlarge 326KB, 1024x1024 78 Ch2-69 Crossed Loops - 806 MHz Transmission Line Length = 0.26-meters Interconnects the Two Loops Azimuthal Pattern: FOUR-LOBES Significant Loss in NULLs for RHCP
