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TOPIC: 2 meter 5 element yagi

2 meter 5 element yagi 7 years 7 months ago #68

  • ap2aum
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Hello fellow Hams,

Can someone help me in making a 2 meter 5 element yagi. I have the plan with me but i would need physical help in actually preparing it. if there is a local company that makes them on payment kinldy provide me the details. i would be willing to pay and get it made.

thnx 73s
ap2aum
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Re: 2 meter 5 element yagi 7 years 7 months ago #74

Can not do any physical help but i can provide you the full detail of 2m 5 ele. yagi.

wait for for few days. i will send you InshaAllah.

regards

ap2gh.
Ghulam Hussain (AP2GH)
Mobile : 0300-8666169
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Re: 2 meter 5 element yagi 7 years 7 months ago #76

  • Riffad Khan AP2RF
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kindly also check with AP2UK , he has good grip in 3 to 5 elements Yagi.
Muhammad Riffad Khalid
AP2RF
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Re:2 meter 5 element yagi 7 years 7 months ago #82

  • Asad Khan AP2ASD
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Dear AP2AUM,

Usually hams experiment making HF antennas while VHF/UHF antennas are just purchased because you are unlikely to match their feed point impedance to that of the coax and the source, which would be 50 Ohms.

If you try designing your own antennas, you must have certain equipments such as analyzer, balun, and tuner. If a VHF yagi is the only thing you will ever homebrew, then analyzer would be more expensive than a well-resonant Cushcraft yagi. In fact, it’s always good to own one. Baluns are available in a variety of ratios. After you have made an antenna, use an analyzer to measure SWR, and then find the appropriate banun, such as 2:1, 4:1, 9:1 and so forth. You might also want to try gamma match to bring up a low impedance to 50 Ohms. The bad thing is that you can’t use a tuner above 54 MHz because it steals most of your output on higher frequencies. Plus…I don’t know if there’s any for 2 meters/440.

If you want to practice some ‘hide and seek’ with the boom and elements, you follow the good old formula; a driven element, a reflector, and director(s). A driven element is a resonant dipole, aprox. λ/2 long. The reflector is longer than ½ w by 5% and spaced at 15 to 20% of the λ, behind the DE, which would be the opposite direction of the main lobe. Directors, shorter than DE by 5%, are placed in the front by the same amount. Make sure to use large diameter elements to reduce SWR variations.

Hope this helps.
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Re:2 meter 5 element yagi 7 years 7 months ago #84

  • ap2aum
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thnx kc2vob and Rf for the lead, appreciated.

will start work on it after this weekend and will keep you updated how the project goes.
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Re:2 meter 5 element yagi 7 years 7 months ago #109

Dear AUM,
Found a good article on Recycling TV Antennas for 2-Meter Use. Maybe this helps.

Attachment 9611034.pdf not found

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