The interface can sometimes become unresponsive especially during the transmit.
Unfortunately there is a price for this simplicity which is the sensitivity for RFI. The logic levels are the simplest and most cost efficient implementation because those the voltages used by the radio’s digital internals. This is the default Digirig configuration and it is supported by the interface from the very first revision. Paired with the Middleware Software such as FlRig it allows operator to fully control the radio from PC and opens good potential for remote operation. Typically the command set includes all of the radio’s controls including VFO, band selection, preamps, tuner and most importantly transmit command.
This interface features distinct TxD and RxD serial port lines which operate at a logical level of 3.3V. We find this option in mid-grade modern rigs like Yaesu’s FT-8xx series and Xiegu. Let’s look at all the rig control options we encounter in modern and classic amateur radio transceivers and the ways to realize their best potential for digital modes and remote operation.