In many instances using a separate receive antenna connection is an advantage, e.g. high power and pre-amp usage, squezing every last dB of nF out of the system, or just plain saving on external relays.
I have installed separate SMA antenna receive connectors as pictured below:
![](/pictures/yaesu/ft-847_separated_2m_70cm-1.jpg)
Here you see coaxial connections to the receive circuit (marked V and U), with the cables unplugged, and a small area in front scraped clean for soldering. Also visible is a sligth enlargeing of the rear air grille to receive one of the SMA connectors. Note also that the 144 antenna connector has been replaced with an N-connector - something Yaesu should have done from the factory!
![](/pictures/yaesu/ft-847_separated_2m_70cm-2.jpg)
Now the 144 receive connector has been mounted and soldered in place.
![](/pictures/yaesu/ft-847_separated_2m_70cm-3.jpg)
and the 432 as well. The original connection from the Tx/Rx switching circuit has been restored, and everything works as before, with the exception that you now have the option of using a separate receive connection, with a gain of almost 1dB noise figure! Finish off by securing the SMA connectors with judicial usage of Lock-Tite or Epoxy.
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