• Menu 001: EXT MENU set to ON
• Menu 037: DIG GAIN set to 15 (Exact value can be fine tuned here, Signalink TX knob, or PC audio device settings)
• Menu 038: DIG MODE set to PSK31-L
• Menu 075: RF POWER SET as desired
• Multi-Function Row P: Make sure DSP settings are off.

Open up the Case by taking out the screws on the front panel, and sliding everything out the front.

• Install Jumper Wires per manufacturers directions for use with an 857d.
• Place the jumper across both pins of JP2
• Place the jumper across both pins of JP4
• The Jumper should only be on 1 pin of JP3

these instructions and a basic diagram are available here: https://www.qsl.net/na4it/slusb/slusb_ft857d.html