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Portable Yagi-Uda satcom antenna

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Assembled Yagi-Uda antenna for UHF satcom

For covering wide frequency range the Yagi-Uda antenna is not best choice. NanoVNA came with quite cool design which benefits from resonation between radiator and first director causing lowering gain but making it very wideband.

MMANA model of the antenna and currents on elements.
Radiation pattern of the antenna in vertical and horizontal plane.
Unusually wide frequency range of Yagi-Uda antenna.
Impedance of the antenna across 240 to 320 MHz.
Detail of BNC connector feeding dipole.
Disassembled antenna.
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Nagoya REVEX NA-660S Gooseneck UHF 400-470MHz SMA-Female Tactical Antenna

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You were not clickbaited it is official name on Aliexpress 🙂
If you wondered how this antenna performs how is its SWR or what is hidden inside fiber-glass tube check the pictures below. Teardown of antenna is irreversible process beacuse everyting is glued together.

The antenna with reverse SMA on Zastone M7 radio.

I dont know how manufacturer measures the antenna or if this design is one of that “dualband” because the resonance frequency is somewhere between VHF and UHF band but it looks like 300 MHz is a sweetpot.

NanoVNA measuring Revex antenna.
Partially diasambled fiber-glass tube.
Sleeve-dipole antenna inside.

Inside the antenna there is very interesting combination of sleeve monopole (counterweight) with normal mode helix as radiator. Further investigation of antenna will follow next time.

There is antenna specification from seller on Aliexpress:

Brand:REVEX (Nagoya)

Connector Type: SMA-Female

Frequency: 400-470MHz (400-470MHz will be better signal)

Gain: 3.5dBi

Max Power: 20Watts.

V.S.W.R: Less than 1.5.

Impedance: 50ohm.

Antenna length:330mm