Yaesu FT-847 Operating Manual

Also see for FT-847: Technical supplement Technical supplement Technical supplement Modification

Contents

20 FT-847 OPERATING MANUAL(1) POWER SwitchThis latching-type switch turns the transceiver on andoff. Push the switch in to turn the transceiver on, andpush it again to turn the power off.(2) MOX SwitchThis latching-type switch is used to switch the trans-ceiver manually into the transmit mode (it therebyduplicates the action of the microphone Push-To-Talk[PTT] switch). Press it in to activate the transmit mode,and press it again to release the transceiver back intothe receive mode.CAUTION: Be sure to have an antenna or dummy loadconnected to the appropriate antenna jackwhen this switch is pushed. Failure to do somay cause damage to the transceiver’s finalamplifier stage.Front Panel Controls & Switches(3) TUNER SwitchThis switch activates the optional (external) FC-20Automatic Antenna Tuner of the optional ATAS-100Active-Tuning Antenna System. A momentary touchof this switch places the Antenna Tuner in line (recep-tion is not affected). Pressing and holding this switchin for ½ second activates the Automatic MatchingMode, in which a carrier is generated and the tuner orantenna’s microprocessor makes adjustments so as topresent a 50Ω impedance to the transmitter’s antennaport.CAUTION: Be certain to have an antenna or dummy loadconnected to the appropriate antenna jackbefore initiating Automatic Antenna Tunermatching procedures.(4) PHONE JackThis ¼” 3-pin (“stereo”) jack is used for connectionto your headphones. When a plug is inserted into thisjack, the internal (or external) speaker will be cut off.This jack’s impedance is optimized for use with 16Ωto 32Ω headphone types.