Skip to main content
  1. Equipment/
  2. Handhelds/

Radioddity GD-77


Product pageOpenGD77 FirmwareLatest CPS

This is probably the first DMR capable radio that is made for amateur radio. Obviosly not per default, but thanks to OpenGD77 it is now suited for amateur radio usage.

udev-Rules for Linux #

# USB rules for GD-77
# Place this in /etc/udev/rules.d/ to let all users talk to the radios by USB.

SUBSYSTEM=="usb", ATTRS{idVendor}=="15a2", ATTRS{idProduct}=="0073", MODE="0666"

# HIDAPI/libusb
SUBSYSTEM=="usb", ATTRS{idVendor}=="15a2", ATTRS{idProduct}=="0073", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1fc9", ATTRS{idProduct}=="0094", MODE="0666"

# HIDAPI/hidraw
KERNEL=="hidraw*", ATTRS{idVendor}=="15a2", ATTRS{idProduct}=="0073", MODE="0666"
KERNEL=="hidraw*", ATTRS{idVendor}=="1fc9", ATTRS{idProduct}=="0094", MODE="0666"

# HIDAPI/hiddev
## We need to unbind this device, otherwise LibUsb will fail to SetConfiguration() and ClaimInterface()
# For Bootloader (usbhid)
KERNEL=="hiddev*", ATTRS{idVendor}=="15a2", ATTRS{idProduct}=="0073", MODE="0666", RUN+="/bin/bash -c 'ID=$(IFS=/; read -a array <<< %p; echo ${array[-3]}); echo $ID > /sys/bus/usb/drivers/usbhid/unbind'"

# OpenGD77
KERNEL=="ttyACM[0-9]*", SUBSYSTEM=="tty", ATTRS{idVendor}=="1fc9", ATTRS{idProduct}=="0094", MODE="0666", GROUP="dialout", SYMLINK+="OpenGD77"

If you want do reload udev with the new rules, run:

$ udevadm control --reload-rules && udevadm trigger

Original boot tone melody #

The originally used boot-up melody. I’m not sure if it changed already, but this was on my GD-77 when I first installed the OpenGD77 firmware.


My boot-up picture #

Normal display settingsInverted display settings
OE7DRT Boot-up picture white
OE7DRT Boot-up picture black (inverted)

Importing DMR-IDs #

Open Extras » Download callsign database and fetch the data that you want.

Import menu

Set the region to the desired MCC that you want to import. You can also use the inactivity filter that fetches only recently active DMR-IDs. Or you can import DMR-IDs from a file.

Import dialog

I usually import them from a CSV-file. The file that I use contains all the austrian callsigns plus a few other callsigns, that I regularly see. So I need to import about 2000 callsigns. Well, I do not use DMR, D-STAR or C4FM so often; so I don’t import anything at the moment. But I came across this site again and I thought I could update this list again (after nearly 2 years there are a few new callsigns in this list – about 2000 new callsigns).

If you don’t have a proper file to start with use this one here. It contains these regions: 232, 262, 263, 264, 222, 228.
📂 Download (~242KB)

Or: download your own set of DMR-IDs with the regions you want. You can also download only some federal states (like 2327,2328) if you don’t want all entries from 232. Read along here for some instructions about this.

Band scope (Spectrum sweep scan) #

I’m not sure when this feature was implemented, but OpenGD77 now supports an easy to use band scope on the GD-77.

Press and hold the hash key # when in VFO mode to enter this feature.

Output power on 2m #

2m band output power

Power settingOut power (device 1)Out power (device 2)
+W-7.50 W7.60 W
5W5.31 W5.40 W
50mW376 mW152 mW
1W1.30 W1.35 W
2W2.37 W2.14 W
3W2.90 W2.70 W
4W3.76 W3.40 W

I have two devices and they differ on some settings (50mW setting for example).

Output power on 70cm #

70cm band output power

I have only measured one device as devices may differ largely.

Power settingOutput power
50mW917 mW
250mW925 mW
500mW1.86 W
750mW1.49 W
1W1.67 W
2W2.35 W
3W2.96 W
4W4.22 W
5W7.50 W
+W-8.41 W