FTDX-1200 TX red light flashing

[Don't know anything about the FTDX-1200 specifically, but make sure you are set to a freq within one of the legal ham bands. Perhaps the flashing indicates an out-of-band condition where transmitting is not permitted].

 

You must be within a ham band.
You must not be set to SPLIT, or TX - Offset out of the band.
Make sure CAT is not connected. (computer could be asking for Xmit)

If non of that works.... Do a full reset.

GL

 

It is a part of my key that shorts the contacts, essentially holding the key closed. The radio will display an error, the flashing red light, if it is powered up with the PTT or key engaged.

 

I did full reset. I detached all accessories from the radio except the power cable when trying all the possibility,
Frequency set within 40M, NO SPLIT and NO TX OFFSET

 

Thanks for the update. My radio already free from any accessories.

 

I did not read every word of the back and forth so if this is already covered sorry. If the radio is in this condition and will not recover, is the following occurring on your radio? When the TX light is flashing the RX audio is muted? If the Moni switched is pressed is the receive audio and receive functionality restored? But still no transmit. If it does it is because the radio is in or thinks it is in a transmit condition. On the radios, I have fixed with this problem, either the PTT line or one of the dot/dash lines were in the TX state. I cant say this is true for every condition just the ones I have fixed.

 

Since it rcvs OK, I don't think it is stuck in XMT. Try to turn the TUNE function on/off (short press TUNE button).
I fixed a tuner issue by reseating the flat ribbon connector directly behind the TUNE button.
Mike N3PM

 

Re the shorting bar: A great many straight keys have them, inherited from way back in the 19th century. On cross-country telegraph lines, e.g. along railroad lines, the keys and the sounder (the thing that went "clack" when an incoming dot or dash arrived) were connected in series. This is also the background of some of the connections for teletypes leading up to the famous ASR33 and on into more modern terminals, called "current loop". Current would be supplied by a battery somewhere in the system and would flow all around the system. (For really long circuits, lots of resistance, the circuit would be broken into smaller loops with extenders that were basically just relays connecting one loop to the next.) If you were not holding down your key, the circuit would be broken and nobody could hear anything. So they put on the shorting bar to keep the current flowing, you just un-short it whenever you want to send.
Probably the most famous version is the great J-38 key, many of us bought those from military surplus after WWII.
Bob, WA9D