I've been using FT8 on my Yaesu FT-450D for quite some time. I decided to try to talk on phone frequencies and discovered neither one of my mics will transmit. My mics are the original hand mic and a Heil headset. I've tried all bands and cannot transmit on any of them. I had successfully talked on the radio but not now. The only change I have made was to change from a switching power supply to a linear power supply. The radio will not transmit on either supply. It only transmits in digital modes. Does anyone have any ideas?
My Xiegu G90 radio has to have the output from the 8-pin connector in the back set to line instead of mic for it to transmit a digital signal into my SignalLink sound card. Could it be that the FT-450D has the same type of settings. which may need to be changed back again from line to mic to send SSB or voice.
It appears that the 450 has a number of complex settings that may well be the source of your problem. Here's some feedback from other owners who've learned some interesting features on their radios:
I'm thinking that your trouble is merely an unintended setting in the menu system.