Bi-quad antenna 430 - 440 Mhz (plans and tests)

Hello everyone, in the attachment you will find the plans and results measurement for a bi-quad antenna (430 - 440 Mhz). For the moment the antenna is located in the attic and in use for 3387 station, pointed to North-West, aprox. 30 degrees elevation.
Biquad antenna SATNOGS.pdf (1.6 MB)
I hope in next 2-3 days to be outside, on mast.
Regards,
YO4DFT - Cristian

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Wow, thanks Cristian, that is a great design.

Maybe just pointing it strait up can already have a fine reception, similar to my 3 element yagi’s.

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You gave me an idea, and a possible solution. I have a strong perturbation on 436.750 and 437.000 mhz. I checked everything, groundings, cables, etc. Last evening, when I put this antenna in attic, I discover the perturbation almost disappeared (my conclusion, the perturbation is from something around me, not from my equipments, or house). I shall mount the antenna on mast, pointed to NW and 30 degrees elevation, and if the perturbation will be again, I shall pointed strait up (in this way I shall minimized the low angles).
Thank you !
Cristian - YO4DFT

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Hi Cristian, I looked into your pdf describing the biquad antenna and you are stating there, that the antenna has vertical polarisation. But it can not be true, when the feedpoints are left and right and in the same time, the reflectors are horizontal. Nevertheless the antenna can be clearly used for sat reception… Best regards.
Tomas OK2PNQ

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Hi Thomas, this morning I’ve looked at antenna and said… it’ vertical or horizontal polarisation ??? Have to check again. Btw, the results are better than previos antenna.

Thank you,
Cristian - YO4DFT

And this is an example, LEDSAT at only 3 degrees elevation.
https://network.satnogs.org/observations/10795030/

Good evening Tomas,
Yes, you are right, I made a mistake. Its horizontal polarisation, so I have to rotate it.
I shall try to rotate tomorow morning, if weather will be favorable. The problem is the tilt, I dont have for the moment solution for other elevation, only zero elevation.
Also, I presume the results will be better. As I said, the performance was better than other home made antennas I used.
Thank you very much for your observation,
Cristian - YO4DFT