Timz DMR Repeater
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Radio info and Codeplugs - Tools that can enhance your DMR usageHow to enable APRS-GPS on your 878
"I've been doing APRS-GPS in analog form for years... I imagine it's even better via digital DMR"
Maybe not.
if someone wants the best chance that their coordinates will be heard and then to appear on APRS.FI, doing this via analog on 144.390 is far better. There are many many many more analog digipeaters and I-Gates in our area - than DMR repeaters. And with analog, it's always the same simplex frequency.
Ham analog APRS-GPS got it right; a dedicated frequency... continent wide... that has no other use. If you listen to 144.390... it's crammed with APRS transmissions; GOOD !!! It's not causing any interference... not competing with anything else. Using this one analog simplex frequency for APRS-GPS, you will probably be heard no matter where in the US you travel.
Sending this data via DMR - each APRS-GPS transmission (and roaming "ping")... busies that TimeSlot. Although for just a few seconds... it still may cause a busy signal to someone else trying to transmit voice through the repeater at the same time on that same TimeSlot.
With some of these dual-band dual-mode DMR radios, you can have analog APRS-GPS happening on 144.390, while the other band is for DMR.
Right now with Digital APRS-GPS... there isn't a nation-wide simplex frequency assigned to receive these transmissions; no standard exists (yet). To send APRS-GPS digitally through DMR, you have to tell your radio what specific DMR repeater to use (and group-number and timeslot).
What happens if you drive out of range of that DMR repeater ???? Oh yeah, you can enable roaming on your radio and help with switching repeaters once you're out of the area, but using that for continued APRS-GPS transmissions is a crap shoot; no guarantee. Or you will need to reprogram your radio each time you travel out-of-range of the assigned APRS DMR repeater in your radios codeplug.
But, there are more uses for APRS-GPS than just getting a "blip" on the APRS.FI map; and in some instances digital APRS-GPS "DAPRS" may have advantages over analog.
My DMR repeater will forward digital APRS-GPS transmissions through to the network; and it's OK for your radio to do so. Have fun and enjoy the hobby.
Note: Anytone radios will allow analog APRS-GPS transmissions in the background while the radio is sitting on a digital DMR channel. For setup instructions on how to do this, download this WORD doc:
http://tim-yvonne.com/ham/dmr/radios/D578/D578-APRS.doc
Click HERE for help in configuring APRS-GPS on a 878 radio
Tim
N8NQH
