Yaesu DR-2X Installation Instructions Manual page 7

Installation of the DSP firmware
Note: Install the RX-UNIT firmware before attempting to Install the DSP firmware.
1. Turn the DR-2X/XE [POWER] switch to the "O" (OFF) position.
2. If the LAN-UNIT is not being used, proceed to step 4.
Remove the rubber cap at the rear of the top case.
3. Through the hole at the rear of the top case, move the slide switch (S6013) toward the "NORMAL" side
("Right" side as shown in figure).
4. Connect the SCU-20 PC connection cable to the ACC jack on the DR-2X/XE rear panel.
5. Touch and hold the DR-2X/XE LCD screen while turning the DR-2X/XE ON.
6. Press the [SETUP] switch button, (although "PUSH SETUP" message is displayed on the screen).
"DSP  COM" will appear on the display.
Switch (S6013)
SCU-20
7
NORMAL
DC 12 V - 15 V (EU)
AC 100 V - 240 V
(USA, EXP, AUS, CHN)