Linked Questions
15 questions linked to/from What is a Gamma match in the context of the driven element of a Yagi antenna?
19
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1
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4k
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How does moving a feedpoint off-center in a dipole affect the resonant frequency and resistive load?
Specifically, I understand that OCF dipoles change the SWR, but does it do this via reactance or resistance, or both?
- 1,194
4
votes
3
answers
2k
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Suggestions for HF antenna for occasional use on my sailboat
I have had a license since I was a kid, but have not touched anything ham radio related in years. I have been thinking about diving back in and combining it with my sailing. I'm looking for thoughts ...
- 171
2
votes
2
answers
2k
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Yagi: split or solid driven element?
Short question:
What are the advantages and disadvantages of using gamma (solid element) or beta (split element) matching a yagi?
Long question:
A while ago I built a coil loaded yagi for the 20M ...
- 1,199
1
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2
answers
3k
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How to make a loop antenna for HF?
While researching this answer, I came across information that indicates that a many good Low Frequency/ Very Low Frequency antennas are loops, with high directionality and good overall characteristics....
- 6,178
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2
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2k
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Trying to identify and understand this antenna design - ground independent dual band vertical
This is the insides of a common dual band antenna 2m/70cm, made by diamond or nagoya.
its generally labelled as: 1/2 wave radialless (144MHz), 2 x 5/8 wave radialless (430MHz)
Its meant to be ground ...
- 143
1
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1
answer
2k
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How does a gamma match on a dipole work as a balun?
I have a resonant half wave dipole which is one continuous length and not separated in the middle, fed using a gamma match, and with the braid of the coax joined to the exact electrical center of the ...
- 3,665
5
votes
2
answers
1k
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How to adapt commercial VHF yagi for 2 meter amateur use?
I recently acquired a Decibel 3-element VHF Yagi that was formerly in commercial service. I connected my MFJ-259B antenna analyzer to the antenna and found its minimum SWR at 155 MHz. I have not ...
- 183
2
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1
answer
2k
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Is it possible to determine if I'm adjusting gamma match in correct direction with an SWR meter and if yes, how?
I've recently obtained a Quad Loop antenna for 2 m and 70 cm that's fed through gamma match, as shown in the picture:
The shorter metal bars are connected to the hot side of the BNC, while the longer ...
- 2,873
2
votes
1
answer
2k
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Balun and impedance matching suggestions for dipole antenna
I'm a newbie who is attempting to build a half-wave dipole antenna that will be located in the rudder of a sailplane. 123.3 MHz is the most important frequency to me, although it's reasonable to ...
- 31
1
vote
2
answers
801
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Multi-part question. correct length of rg-8x coax to connect 2 meter HT to 50 ohm yagi
What it the optimal number of wave lengths of RG-8X coax to connect my Icom IC V80 HT to a 50 ohm Jetstream JTBM270 Yagi (3 elements 2m/5 elements 70cm)? Odd or even number thereof?
Will running the ...
1
vote
1
answer
746
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How to assemble an antenna (impedance matching methods)
I got the following plans off Martin E. Meserve's website.
How do I go about assembling the antenna once I have the elements and boom? What is the impedance of the driven element? Do I need baluns ...
- 61
2
votes
1
answer
500
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Will these wires affect antenna performance negitavely?
We moved into a new house, and I noticed these wires sticking up for some sort of tent thing for shade.
•I tested the wires to the 3rd prong in the outlet, and it showed a DC dead short to ground.
•...
- 7,580
2
votes
2
answers
308
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Balance of gamma / delta match
A center fed dipole, with equal arm lengths, is a balanced device.
If it is fed using a gamma match - does it change (the system) to be unbalanced?
- 167
2
votes
2
answers
228
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Is there any difference in the voltage and current distribution for a half wave dipole fed in the middle, or fed with a gamma match?
Is there any difference in the voltage (potential difference wrt center) and current (rate of flow of electrons) distribution for a half wave dipole fed in the middle (dipole cut in the middle,) or ...
- 3,665
3
votes
2
answers
196
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VHF Balancing, necessary? Methods?
This is a question about power dissipated due to radiation and ohmic heating caused by common mode current in the coaxial shielding, specifically at VHF frequencies.
When a balanced antenna (such as a ...
- 160