I’m trying to get the most out of my Icom 7300 and recently I was given some good information by a fellow Ham on Facebook. Operate split mode or as it’s called in the user guide, split operation in WSJT-X. I was trying to operate dual mode (JT65 & JT9), but was unable to transmit past 2700 Hz (passband limitations). Since JT9 normally starts above 2500 Hz this didn’t leave me much room.

Split Mode, Split Operation

This does a couple of things. 1. Allows me to transmit above 2700 Hz. 2. Produces a cleaner signal.

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“Split Operation: Significant advantages result from using Split mode (separate VFOs for Rx and Tx) if your radio supports it. If it does not, WSJT-X can emulate such behavior. Either method will result in a cleaner transmitted signal, by keeping the Tx audio always in the range 1500 to 2000 Hz so that audio harmonics cannot pass through the Tx sideband filter. Select Rig to use the radio’s Split mode, or Fake It to have WSJT-X adjust the VFO frequency as needed, when T/R switching occurs. Choose None if you do not wish to use split operation.” – WSJT-X User Guice v1.7

I’ll write more on split operation and Lock Tx=Rx later, but here’s an example of running split using WSJT-X on a Raspberry Pi. As you can see in the video I found 5 watts to be sufficient. Earlier on 15 Meters I made several contacts in Brazil using just 5 watts.

Of course this can be done on a Windows computer too. It’s an function of WSJT-X. I’ve been using it daily on both of my computers.

I’m alway interested in comments, so please send me something below. Best wishes, 73 and good DX. – Rich, K0PIR