There has been a lot of misinformation about using this capability. This article discusses:
- How to use the built in GPS to report into APRS.FI for APRS location
- How to set up a TYT MD-380G UHF version for this feature
First Step - Getting a GPS signal lock
Chances are that your radio's GPS was last tested in China, at the factory or never at all.
You may need to wait a while to get a signal lock. Be patient.
But first, program the following into your radio to get the GPS actually working.
Create a new "Digital Contact" and label as "APRS-310999". Make the contact "Private Call". Set the Call ID to "310999". Do not enable a call receive tone.
It should look like this when done
Create a new channel on a frequency (UHF or VHF does not matter) of your choice, such as the one used on your hot spot, like an RF Shark OpenSpot. Label the channel "APRS GPS ON" . Enable the "Send GPS Info" and "Receive GPS Info" settings.
Select the Contact as the "APRS-310999" one created.
Select an appropriate group you may already have in your radio that includes TG 9 and any of your other favorites. This is what enables voice communication on the same channel on your MD-380, but using a different talk group than TG 310999 which is for GPS only.
Use the same color code as your hotspot. You may want to use TS 2 if in use with your Open Spot.
Make sure there is "None" in the Privacy setting.
Select "1" in the GPS System setting.
Your channel should look like this when done
Word about Group List: This is optional, but setting up an RX Group List allows you to monitor multiple TG at the same time.
Go to the GPS Settings in the CPS and enable GPS Revert Channel to the channel you created called "APRS GPS ON"
Set your default GPS report interval to a value of "180". If you select a smaller value, the GPS will affect your battery life.
Set the Destination ID to the Digital Contact you created called "APRS-310999"
When finished, it should look like this
Now, create another Channel
Follow every step as above, but the only thing to do different is to not enable a GPS System. So, instead of "1" make sure that box is set to "None". Label this channel "APRS GPS OFF"
Before you write file to radio
Put both of the channels created into a new or existing zone.
Check to make sure GPS is enabled in the Menu Item setting like below
Write the file to your radio and then go to the channel you made called "APRS GPS ON"
Key your PTT for a second or so.
Go put your radio outside or where it could get a good GPS signal. WAIT about 10 minutes!
You will get a GPS lock when the globe icon changes from red to green.
Confirm you have GPS Lock
Go into your MD-380G radio menu under "Utilities" and "GPS BeiDou Info"
You should see your latitude, longitude, altitude and number of GPS satellites your radio can receive.
If you do not have that, you either set something up wrong or did not wait long enough in a good location for a satellite lock. Try again. If you have location data, proceed as follows:
Log in to your Brandmeister Network account and go to the SelfCare section. The below URL "should" work if you can not figure it out. https://brandmeister.network/?page=selfcare
Select "Chinese Radio", enable a 60 second APRS interval and select the appropriate SSID for your call sign and icon. Generally, a portable HT should be -2, a mobile, -7 or -9. A detailed table to consult can be found here.
See what happens next at APRS.fi
If you have done everything correctly and key your PTT and have a GPS signal lock, you should be able to now see your DMR MD-380 on aprs.fi.
NOTE: This will only work through a hotspot. Many repeater operators may not let private calls or TG 310999 pass through, so just want to be clear about that.
Next Steps & Future:
Much like there how APRS has RX only iGateways, it is entirely possible for different areas to start supporting a DMR gateway by re-purposing a hotspot or simplex link radio using MMDVM but for "receive only". This will then enable your position to be shared without having to use a hotspot or repeater which may disrupt traffic. Repeaters owners say this is an issue. This approach in adding a separate gateway will solve the issue AND create uniform adoption by using the same frequency like 144.39 for APRS. Perhaps DMR uses could use one of the proposed 427 MHz channels in the simplex channel plan found here.
Actual use cases:
Maybe you travel? Take your hotspot with you in the car and talk on your DMR HT? Now, you will have GPS APRS on aprs.fi from anywhere (That has mobile phone coverage)
Via simplex communication, you and another radio can exchange location and altitude data independent of any infrastructure at any time.
Excite the amateur radio community to continue development for non-network infrastructure use cases possibly by incorporating local cached maps, mesh networks and iGateways on coordinated frequencies to support another layer of communication and situational awareness.