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Antenna_e

Homemade Antenna used for satellite and HF communication.

This page edited the article on a Japanese page. by JE2TLZ

Top Loading Verttical Dipole

Upper Element by 0.9m above from the coil at the time of 1.6m last from the coil.
The length of the Loading Coil is 106mm, and 96mm in the diameter.
Photograph of Hi-Q Loading Coil

BandLoading CoilLower side element
14MHz14Turn4.535m
18MHz8T(short 6T)3.69m
21MHz5T(short 9T)3.20m
24.9MHz3T(short 11T)2.70m
28MHzno(short ALL)2.20m

The frequency is switched by manual control.
The coil is short-circuited because of bottom toward the center.

I measured Verttical DP the miniVNA → VerticalDP14-21.png,VerticalDP25.png

Loop Antenna

146MHz 3ele Loop ANT Gain 10.0dbi SWR2> 3.4MHz(MMANA)
ElementSpacingLoop DiameterCircumferenceDiameter
Re390mm681.2mm2140mm3.0mm
Ra--651.620473.0
De450627.719723.0

I measured 145MHz3eleLoop the miniVNA → 3ele_loop_2m2.png

435MHz 4ele Loop ANT Gain 11.9dbi SWR2> 8.7MHz(MMANA)
ElementSpacingLoop DiameterCircumferenceDiameter
Re148mm232.3mm729.8mm3.0mm
Ra--218.06853.0
D1193.5213.8671.73.0
D2195211.0663.63.0

This 4eleLoop changed to wide a little more 3eleLoop because vertical pattern was too narrow.

435MHz 3ele Loop ANT Gain 10.2dbi SWR2>10.6MHz(MMANA)
ElementSpacingLoop DiameterCircumferenceDiameter
Re127mm231.7mm728.0mm3.0mm
Ra--218.0685.03.0
D1173210.4661.03.0

The material is wood, a plastic stick, an aluminum line, and a pressure terminal.
All Loop ANT is Impedance matchings are only 1:1 Balun.(Bazooka Match)BazookaMatch.png

1269MHz 4ele Loop ANT Gain 11.7dbi (MMANA)
ElementSpacingLoop DiameterCircumferenceDiameter
Re41mm79.2mm248.9mm1.2mm
Ra---77.6234.81.2
D16972.2226.71.2
D27670.32211.2
The material is wood, an Brass line.

The Satellite QSO me with a portable transceiver with this small antenna.
(AO-51 L/U mode, Only 1W QRP!) Rig00640s.jpg

Yagi-Uda Antenna

145MHz 3ele Yagi-Uda ANT Gain 9.0dbi SWR2> 2.3MHz(MMANA) 270g
ElementSpacingLengthHeightDiameter
Re248.1mm1010mm6.0mm
Ra-hafeFD-940.523mm5.0
Di558.2895.55.0

I measured 145MHz3eleYagi the miniVNA → 3eleYagi_2m.png

435MHz 5ele Yagi-Uda ANT Gain 11.3dbi SWR2> 13.3MHz(MMANA) 220g
ElementSpacingLengthHeightDiameter
Re100mm343.9mm5.0mm
Ra-FD-304.516.5mm4.0
D1132.33145.0
D2196.42975.0
D3228.82835.0
old_Ra-FD-304.517.5mm3.0

The material is wood, an aluminum pipe(5&6mm), and a brass pipe(3&4mm).
5ele Yagi ANT is Impedance matchings are only 1:1 Balun.

Point of Design
Reproducibility improves when designing in wideband.
Impedance falls though it becomes wideband when the element is made fat, and Gain rises, too.
To raise Gain, the interval of Di is widened more than Re.

The antenna simulation is confirmed.

The difference of the resonance frequency according to the shape of the loop was examined.
Loop modelSideLoop lengthAreapercentageMMANA-f0NEC2-f0differencepercentage
Triangle0.667m2.0m0.157m249.4%165.77MHz165.15MHz-0.62MHz103.8%
Quadrangle0.5002.00.25078.6%163.96163.21-0.75102.6%
Octagon0.2502.0 0.30295.0%160.96160.12-0.84100.7%
16polygon0.1252.0 0.31498.7%160.52159.06-1.46100%
Circle0.3182.00.318100%????
(Single loop,Line diameter 3mm)

The difference between the simulation and the measurement was examined.
AntennaMMANA(miniNEC)NEC-2 for MMANAdifferenceMeasured valuedifference
146MHz3eleYagi146.1MHz145.8MHz-0.3MHz146MHzClose value
435MHz5eleYagi436.5432.5-4.0432Close value
146MHz3eleLoop147.5(octagon)147.2(octagon)-0.3146It is lower
146MHz3eleLoop146.14(16polygon)146.12(16polygon)-0.02146Close value
435MHz4eleLoop437.5(octagon)437.1(octagon)-0.4433.5It is lower
435MHz4eleLoop433.98(16polygon)433.81(16polygon)-0.17433.5Close value

NEC-2 calculates the ground effect.

MMANA Data file of all antennas

ant_je2tlz.lzh

These Antennas were designed by using MMANA & NEC2 for MMANA.Thank you for wonderful software.

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