Kenwood TH-D72 Basic APRS Functions



I noticed that the manual of this amazing HT is not the best. Actually you have to guess many things to operate the device. Anyway i made the following instructions for basic APRS operation. More will follow.



APRS Basics

APRS functionality is the what this HT excels at. It is the probably the main reason why anyone would consider purchasing this radio, and in my initial testing, Kenwood delivers. The HT has every possible APRS function that I could think of including the capability to digipeat. In this segment, I'll demonstrate Kenwood's implementation of the basic APRS functions

The basic APRS functionality is very easy to set up and fairly straight forward to use. To get started, you only need to go to the setup menu and enter the your callsign into the basic APRS setup. The default data band is the A band, so if you set that to your local APRS frequency (144.800) and hit the TNC button to turn on the TNC, the radio will start decoding the APRS traffic. If you want to Beacon your own position, go to the TX BEACON menu and set up either a beacon interval or turn on smart beaconing. You can set up more advanced APRS settings, but the defaults will get you going.

Once the radio starts to decode APRS data, it will start to pop up a display showing the received stations. This is a sample display of the HT receiving a beacon:                              

When the station beacon is displayed, you can hit the right arrow button to scroll through the other screens to display the remaining info. You perform the same function from the station list menu. Here are the screens that are shown as you continue to scroll through them:


Note that the entire status text is not shown on one screen; more scrolls are required:


Grid Square and distance from your station:


Course and speed:


Altitude:


GPS location:


To display the list of APRS stations received, hit the LIST button which shows three stations at a time:


If you hold down the LIST button, you get five stations at a time with a bit of additional information:



If you hold the LIST button again, it changes the right column to the time received. Once you've chosen your preferred display for the list, the radio remembers the setting for the next time. Using the scroll buttons, you can select a station on the list, hit the MENU button which then allows you to either sort by distance, callsign, or date, apply a filter, or tune to the monitoring frequency indicated by the station's beacon. This particular functionality set is well thought out and very useful.

The method used by the TH-D72 to scroll through the APRS info for each station is another example of simplicity in screen display. As is the case with the GPS screens, it is obvious that the designers went out of their way to make the display large and easy to read. The downside of this approach is that not much information can be displayed at one time. It takes no less than 7 screens of scrolling to view all of the APRS data for one station. The contrasting approach is the Yaesu VX-8 which implements vertical scrolling on the individual screen with a smaller font to show you more information quickly. My personal preference is the Yaesu implementation, but I can also appreciate why some would favor Kenwood's approach.

Sending/Recieving APRS Messages

Sending and receiving text messages using the TH-D72 couldn't be easier. Once you've selected the station you want to communicate with on the station list, you simply press the MSG button, resulting in this screen where you just use the alphanumeric buttons to enter your message:


After entering the text, press the right arrow button to send it, which will result in this screen once a digipeater/iGate accepts it:


When the other station receives and ACK's your message, you get this in response:


When you receive a message from another station, you get a popup with the message display like this:


There are a lot of things to like about the way Kenwood has implemented APRS functionality in this HT, but as is the case with anything, there are also a few areas for improvement. I'll make some comments about some of the things I would do differently in the next update. If there are any questions or others that would like to contribute their views on this HT.

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