Initially, when I was setting up my antenna system, I had an idea to combine the MOXON and Yagi antennas. The reason for this was that it would eliminate a large number of capacitors and transmission lines required for gamma matching, and also utilize natural resonance to improve efficiency and power handling. After the CJU test failed, I discovered that the MOXON has wide bandwidth and small size, so I combined the two.
The structure is shown in the figure, divided into two parts, UV, which are perpendicular to each other.
Physical images
Directional diagram(VHF)
Directional diagram(UHF)
Gain data: UHF 10 dBi, VHF 7.5 dBi. Gain variation within the amateur band is less than 0.15 dB, maintaining good linearity.
Measured standing wave ratio (standing wave ratio displayed - hover to view)
Frequency range (based on VS ≤ 1.5)
UHF 390450MHz
VHF 140150MHz
With careful tuning, it's possible to reduce the standing wave ratio (SWR) of a ham radio operating in the VHF band to below 1.1.
Actual isolation is 40 dB, and the handheld transceiver has minimal cross-talk, making it suitable for dual-band operation. However, actual testing with the UV5R shows that it cannot operate in both bands.
The communication link has been successfully tested and established on both the ISS and SO50.
The gains are often calculated as unit - 1, which means that bandwidth is being traded for gain. The goal of increasing efficiency seems to have failed, but the wider frequency range allows the antenna to operate in more scenarios, such as radio direction finding or selling to amateur ISM communication enthusiasts.
闽ICP备2021006864号-7
闽公网安备35020602002794号