Posts

Stefan Helander

Anytone AT-D878UV / AT-D578UV wishlist

/0 Comments/in /by

This is my wishlist for features / fixes for the Anytone AT-D878UV and AT-D587UV DMR radios. Comments, additions and suggestions are welcome, contact me on sm0rgm@helander.se. Maybe the Anytone people will read it 😉 I will submit it through my dealer as well, for them to forward to the Anytone developers.

  • In the analog APRS message, add the possibility to enter a code which will be replaced by the radio’s current frequency, mode etc so people who sees my APRS packet knows what frequency I am listening on, for example %QRV1 will be replaced by the frequency, mode etc receiver 1 is set to. And %QRV2 will be the corresponding for receiver 2 in my radio. For example, if receiver 1 is set to 434.650 MHz DMR, CC04, TS2 the analog APRS will become “434.650 CC01 TS2”. And if it is set to for example 145.600 MHz FM it would become “145.600 FM”.
  • Make APRS Voice Alert work. The problem is that CTCSS filtering is done before AX.25 APRS decoding. Turn them around, so AX.25 APRS decoding is done before CTCSS filtering. Doing that, Voice Alert would work well on the Anytone since you can select no CTCSS for the APRS transmission but select CTCSS, both TX and RX for the APRS monitoring channel, which also will be used when you press PTT to make a voice alert. (Today, if I set CTCSS RX filter to 136.5 Hz in europe or 100 Hz in US, no APRS will be received at all.)
  • Scanning. When scanning and the scan stops on a channel with traffic, it would be very nice if the radio stayed on that channel when pressing exit to stop scan. Now it goes back the the channel that was selected when scanning started and I have to manually go to the channel with traffic. Also a quick press on the PTT should stop the scanning on the current channel.
  • Roaming. Please bring back so the radio displays which channel it is roaming on. This was the case in early firmwares but disappeared, so now it just displays the channel that was selected when roaming was started. Which means that on a roaming channel, I have no idea which repeater I am using or even which band I am transmitting on. Useless! I know there was a problem if there were more than one channel in the roaming zone with the same freqency, CC etc, the first one in the list matching was displayed even if it was the wrong one. Still, this is better than now knowing at all.
Anytone AT-D878UV analog APRS TX not working
Stefan Helander

Anytone AT-D878UV analog APRS transmissions not working

/0 Comments/in /by

My analog APRS transmissions with the AT-D878UV was not received by any other stations. The problem was that when the codeplug is created (using New in the CPS), the values for Transmit delay and Prewave Time is set to 0 (zero) for APRS and this will not work (probably to battery saving as this is not a problem with the AT-D578UV for example, which will work with much lower values for Transmit Delay and Prewave Time).

Solution:

In the CPS -> APRS -> set Transmit Delay to 600 ms and Prewave time to 600 ms.

Anytone AT-D878UV analog APRS TX not working
Anytone AT-D878UV analog APRS TX not working – solution

Source: https://www.reddit.com/r/AnyTone/comments/han0y5/aprs_problems_the_solution_anytone_atd878uv/

Ana Aprs Tx should be set to “Narrow” according to IARU region 1 bandplan.

What is Transmit Delay and Prewave Time?

I’ve tried to find an explanation to these values online but haven’t found anything closer than “it controls the time after activating the transmitter until data is being sent”. So I tried setting each value, one at a time to it’s maximum and this is what I think it does:

  • Transmit Delay: The radio starts transmitting a packet but it sounds like it waits “Transmit Delay” milliseconds before it starts transmitting any valuebla data. During this time my guess it is filling the packet with zeroes.
  • Prewave Time: The radio pulls the PTT but waits “Prewave Time” milliseconds before it starts to send the packet. During this time, the radio just sends carrier.

If I set the Prewave Time too high, my receiver will not receive and decode the packet. I’ve experimented with values for Prewave Time with different values and between 80-600 ms it seems to be working.