This method of connection is used for transceivers fitted by DIN 8 - BAND DATA output in BCD format. In this way, PC keys the RIG via the COM port, and BAND DATA is acquired in parallel.
PTT signal is connected to RIG via a reduction depending on type of transceiver.
 
Warning : models FT990, 1000 and 1000D needs valid QSK wiring to QSK amplifier. If you not use QSK, join pin #8 (LINEAR) to ground. Otherwise radio will not apply power on TX.
 

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