Yaesu FT-450 Operation Manual

Also see for FT-450: Brochure & specs Reference Manual User manual Technical supplement

Page 2 FT-450 OPERATION MANUALMICON/OFF-SHIFT+DSP ATT/IPO NB AGC BANDDSP/SELFASTA=BMODEMODECLARKEYERPHONESKEYFRONT P ANEL S WITCHES AND K NOBSPHONE JackA 1/4-inch, 3-contact jack accepts ei-ther monaural or stereo headphoneswith 2 or 3-contact plugs. When a plugis inserted, the loudspeaker is dis-abled.NOTE:When wearing headphones, we rec-ommend that you turn the AF GAINlevels down to their lowest settingsbefore turning power on, to minimizethe impact on your hearing caused byaudio “pops” during switch-on.KEY JackThis 1/4-inch, 3-contactjack accepts a CW key orkeyer paddles (for thebuilt-in electronic keyer),or output from an externalelectronic keyer. Pinout isshown below. Key up is 5volts, and key down cur-rent is 0.5 mA.DSP SwitchThis button selects the DSP functions.Available selections are CONTOUR,NOTCH, DNR, and WIDTH.ATT/IPO SwitchThis button selects the ATT or IPO feature. Available se-lections are:ATT:OFF/IPO:OFF ATT:ON/IPO:OFF ATT:OFF/IPO:ON ATT:ON/IPO:ON ATT:OFF/IPO:OFFATT: OFF, IPO: OFFAttenuator is OFF, and the RF preamplifier amplifiesthe incoming signal.ATT: ON, IPO: OFFThe received signal is reduced by 20 dB, and the RFpreamplifier amplifies the incoming signal.ATT: OFF, IPO: ONAttenuator is OFF, and the received signal bypassesthe RF preamplifier, yielding a direct feed to the firstmixer.ATT: ON, IPO: ONThe received signal is reduced by 20 dB, and the in-coming signal bypasses the RF preamplifier, yielding adirect feed to the first mixer.The selection will be indicated in the Block Diagram onthe display.ON/OFF SwitchPress and hold in this switch for one secondto turn the transceiver on or off.NB SwitchThis button turns the IF Noise Blankeron and off. Press this button to re-duce short-duration pulse noise.AGC SwitchThis button selects the AGC characteristics for the receiver.Press and hold in this button for one second to disable theAGC (for testing or weak-signal reception).