Dear Yu, after speaking with you last evening I done more test on FX-4, There is so many problems with machine it is hard to describe to you.
1) Machine is off frequency in CW mode, The machine should be a Plug and play machine, not to change settings in menu. ( No Good)
2) Once I get the CW to transmit and receive on frequency by going into menu. And turn On RIT machine is off frequency ( No Good) .
3) Volume is erratic, I have to turn off machine to make volume stable, after a transmit from another transceiver and received on FX-4 , receiver is muted. ( no Good)
4) There is a loud 650 or 700 Hz tone on all bands, this appears to be some sort of harmonic, and is around 7.039 and 14.050, 10.050. 18.050. ( No Good)
5) SSB has low audio and has tone in with voice. ( No Good)
6) Once the FX-4 is keyed there is a delay in transmit and sends another character. This is heard on monitor receiver, (No Good) this is major problem. Seems to be controlled by CW Delay.
Maybe machine has been damaged during shipment but is totally Useless, I can go No further. The first machine did not have some of these problems so something has changed. larry