You can download the FT-7900 user's manual from the Yaesu web site. The manual indicates (page 15) that the antenna connector is a type M on the USA version of the radio. Type M is what the Japanese electronics industry calls the connector that we refer to as a UHF connector. The male plug for the UHF connector series is the PL-259 and the female jack is typically an SO-239.
The Arrow Antenna web site indicates that the OSJ 146/440 has an SO-239 connector.
So, your cable should have PL-259 connectors on both ends.
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