FT920 - data conector pinout
SCU-17 conector pinout (As viewed from rear panel, not from cable!)
AFSK mode FT-920 pin 1 Data IN (Audio IN) SCU-17 pin 1 Data OUT (Audio OUT) FT-920 pin 2 GND SCU-17 pin 2 GND FT-920 pin 3 PTT SCU-17 pin 3 PTT FT-920 pin 4 Data OUT (Audio OUT) SCU-17 pin 5 Data IN (Audio IN) FT-920 pin 5 Busy SCU-17 pin 6 SQL IN (Busy)
Pin 1 (AFSK Input): Connect this pin to your TNC’s “AFSK Out” or “Mic Audio” output line. The optimum input level is 30mV rms, and the input impedance is 3 k. Your TNC’s audio output level potentiometer will allow you to set the level to the optimum value. This pinmay be used either for 300 baud SSB-mode digital operation or for 1200-baud FM packet. The bandwidth and frequency response are not, however, suitable for 9600 baud operation. Be sure the AFSK-FSK switch on the rear panel is in the AFSK position. For FSK operation (whereby the TNC closes a line to ground to accomplish teletype keying), set the AFSK-FSK switch to FSK, and connect your TNC’s FSK keying line to Pin 1. Pin 2 (Ground): Connect this to the shield(s) of the cable(s) used for connections between the TNC and the FT-920. Pin 3 (PTT): Connect this pin to the PTT line from the TNC. This pin, when grounded by the TNC, places the FT-920 into the Transmit condition. Pin 4 (Audio Out): Connect this pin to your TNC’s “RX Audio” input line. This is a constant-level (100 mV rms @ 600) audio output line which is not affected by the position of the front-panel AF GAIN control. Pin 5 (BUSY): This is a “Squelch Status” pin not generally required for digital mode operation. This pin is held at +5V when the squelch is open, and is grounded when the receiver is muted by the squelch (“nosignal” condition). FT920 Menu settings (dont forget - USB-DATA mode) Menu # Description Value for WSPR/FT4/FT8/RTTY U-45 Packet Freq. Display Offset 0000 U-46 Packet Subcarrier Frequency 2125U Please note, those values are available for regular rtty tones (2295/2125).