View Full Version : APRS no workie

04-07-2014, 02:22 PM
none of my APRS units seem to be logging a beacon at APRS.fi nor openaprs.org. I have an HT and a Byonics TT3...neither of them show online and I've been messing with them for a couple days. Normally, I just turn them on.

any ideas? the units seem to be functioning (I know the HT is receiving aprs signals, and looks to be set correctly in the menus) (8GR)

04-07-2014, 02:45 PM
Have you changed your call sign or is it still KD0MZE? Your last aprs.fi location is from 11/25/2013. Plus all they have is a KD0MZE and KD0MZE-7, don't see a -9 or anything. I just sent a position from my truck a few minutes ago and it showed up on aprs.fi so the system seems to be working.

04-07-2014, 02:51 PM
I've got KD0MZE for my main mobile (fj60) and the HT is registered as "-7" the sites seem to be working well as I can find others. Is there a location online to check things out? maybe email to Byonics?

04-07-2014, 02:57 PM
You probably should do some troubleshooting before asking Byon for help. What are you going to ask him?

When you transmit a packet do you see/hear anything happen immediately after? You will need to be able to hit a digipeater for your packet to find an I-GATE to the Internet. There's only a couple of gateways to the Internet locally and not many more digital repeaters to re-transmit your packet, so it's not automatic that you'll have a path to aprs.fi.

Have you tried driving around to see if you're just not hitting any of them?

04-07-2014, 03:27 PM
I thought I did today, but ...forgot to plug it in. :o My HT for sure isn't hitting a digipeater from my back yard, whereas, I have in the past. I'll do a little more testing. Like that last ping on "-7"...I thought I was tracking us the whole way. I only got out that one time over 8hours.

04-07-2014, 09:47 PM
well...had it on from about 5:15 to 5:45 - not long, I know. but was in Boulder. could have been hard to get to a digipeater. I'll try a different antenna, next.

04-08-2014, 06:53 AM
So what exactly are we talking about here? You mention a VX8R and a Tinytrak3. You don't need a TNC with a VX8R. So do neither of your APRS trackers work? That seems very odd if so. Please list the hardware you're trying to get working. If neither is working then I would suspect a location issue is likely, more power, higher location, etc. Has anyone else been to your location and experience no issues?

You should get at least a couple of position reports showing up in 30 minutes. If your location does not change for a few minutes sometimes aprs.fi doesn't update, but it should for what you were doing. Now if you are in Boulder sometimes you don't have a good aspect to a digipeater, it's kind of an RF black hole in town.

You could try an external antenna or a new location, maybe drive east a few miles, but there might be more going on here. Check cables, make sure they're mated and not broken. Probably in a configuration some place, hard to say. If you're hearing other stations that's a good indication it's likely not an RF issue, e.g. antenna, RF sections. Next step is to make sure you are decoding them, that they are showing up in heard stations, etc. This is where you need to understand modems. You might break squelch but if the header or tail are clipped the packet won't decode, if the levels are too high or low the modem can't figure out where bits start and stop, etc.

If you're using a VX8R the default settings are usually sufficient to get you on the air, just add your call sign. I have customized my FTM-350 to some extent, mostly tweaking the path settings. If want to dump the APRS and digital settings I can take a look. The TT3 I think has a pot you use to set the levels inside but if it's like my TT4 it doesn't have a lot of effect. I will assume since you had it working at one time that you have the correct PTT and signal jumpers (sometimes HTs share functions on connector pins to there might be a jumper you set to make it compatible with mobiles or HTs).

There are delays built into APRS configurations that can cause odd issues like this. You can set the time slot for example, which is to prevent on-air packet collisions. There are other settings that I'll have to think about. The user's manual should explain all these, though. You can set the number of hops a packet is allowed to take, which if it's set too low you don't get enough retransmissions and set too high you get frozen out because it looks like you're flooding the system. You generally don't need more than 2 hops in town and even in Moab that should be enough to make an I-GATE.

04-08-2014, 07:21 AM
So what exactly are we talking about here? You mention a VX8R and a Tinytrak3. You don't need a TNC with a VX8R. So do neither of your APRS trackers work? That seems very odd if so. Please list the hardware you're trying to get working.

You should get at least a couple of position reports showing up in 30 minutes. If your location does not change for a few minutes sometimes aprs.fi doesn't update, but it should for what you were doing. Now if you are in Boulder sometimes you don't have a good aspect to a digipeater, it's kind of an RF black hole in town.

correct. neither are working. I've got the vx-8gr and the all-in-one RTG setup from Byonics. should be "ready-to-go", as they say. i'm pretty confident I have the 8GR set up correctly (GPS on, SSID as "-7", APRS modem to 1200, beacon to auto/every 10min) and I am receiving APRS stations on the 8GR. Can I test one SSID on my HT? (LIke, turn on the RTG and watch the HT for ping?) OR does that confuse the system?

Both used to work just fine. It could be the Boulder thing and, I usually hit a hole near the I25/36 interchange.

. . I'll be doing another test on the way in from Lafayette to Denver today and, I've got another hershey kiss antenna to test today on the way home.

04-08-2014, 09:08 AM
looks like there's a bigger shadow for digipeaters in Boulder County than I figured. looks like I pinged a bit on the way in today. I'll test the 8GR on the way home.

04-08-2014, 10:22 AM
You can transmit with one radio and see stations show up on the other, that's fine. APRS stations themselves don't care one way or the other, it's aprs.fi that digests the reports and sometimes ignores updates. Also digipeaters will sometimes not repeat packets that are transmitted too close in time, but that's fairly rare and you'd have to be flooding the system with transmissions back-to-back.

If both are acting up them I would expect location. Either interference, no close digipeaters, etc. Not all repeater sites have digital repeaters, actually a small percentage actually are APRS repeaters since they would be a second radio and antenna separate from the main repeater. Also there are only a couple that are also gateways to the Internet. I want to say maybe one or two I-GATES exist in Denver/Boulder/Ft. Collins. Except for I-GATEs most digipeaters are not co-located on commercial sites but are usually just hams with a tower at their house, so coverages is a lot worse than you're used to.

A ham can set up a digipeater without coordinating with anyone since they are store-and-forward rather than input/output offset so the network changes all the time. You might have a digipeater running one day and gone the next. Other times they are mobile or portable and only last a few minutes or hours. An APRS digipeater listens on 144.390 for a packet, stores it temporarily and then retransmits on 144.390 some short time later after the original radio has unkeyed. You will hear your packet being retransmitted after your radio switches from TX to RX and your VX-8R will usually then show your station in the list. If it does not then your packet is not being retransmitted for whatever reason.

04-09-2014, 10:59 AM
that's great info on the digipeaters. good example today...the RTG seems to be working fine. I'm still struggling to get the 8GR to send a beacon. I'm receiving them fine. (I saw KD0MZE as a received station) on my HT.

What's a good rule of thumb for squelching? I typically have it squelched a tad more that I would for voice, but not much more.

04-09-2014, 01:51 PM
You can open the squelch completely on APRS if you wish, just turn down the volume. If you want to listen to the frequency then just set the squelch above the noise floor just like you would with voice.

I had to go down into Boulder this morning and made sure to beacon the whole trip.


There are lots of holes along the Diagonal and in town, although a few got through. The trip south was on low power @ 5W and the return trip was at mid power @ 20W. So when coverage is sketchy seems having the extra bump is helpful.

Several in Boulder County repeated through N2XGL in Longmont to the I-GATE N0SPB in Brighton. A couple went directly through N0SPB. The ones up north tend to gateway through W0UPS up by Horsetooth Rez or W0LRA here in Loveland down to KC7SBS in Aurora. I think one went through BVILLE, which is a station up off I-70 near Silver Plume. Some repeated through N0ESQ on Devil's Head (this is a wide coverage location for emcomm that the USFS also uses for the Pike-Isabel NF). If you hover over a beacon you can see the packet's path.

04-09-2014, 03:22 PM
wow....your beacons are much better than mine. what do you have yours set to? smart beaconing? or auto?

04-09-2014, 04:52 PM
Some of the key APRS settings I have:

APRS TX Delay = 250ms

Beacon Inf Ambiguity = OFF
Beacon Inf SPD/CSE = ON
Beacon Inf Altitude = ON

Beacon Status Text = FREQ&SQL&SFT
Beacon Status Text Rate = 1/1

Beacon TX Auto = SMART
Beacon TX Interval = 2 min
Beacon TX Proportional = OFF
Beacon TX Decay = OFF
Beacon TX Low Speed = 2
Beacon TX Rate Limit = 20 sec

Data Squelch TX = OFF
DIGI Path Select = WIDE1-1, WIDE2-1

My Symbol = /k Truck
Position Comment = In Service

SMART Beaconing = TYPE1
TYPE1 Low Speed = 5
TYPE1 High Speed = 45
TYPE1 Slow Rate min = 30
TYPE1 Fast Rate sec = 90
TYPE1 Turn Angle deg = 28
TYPE1 Turn Slope = 240
TYPE1 Turn Time sec = 30

04-09-2014, 09:21 PM
Pretty much the same here - main differences for me on the 8gr is the APRS tx delay is 300ms (default) and I think the beacon interval is 10min. As you know, the RTG is set up from byonics.com. I'm actually not sure how he sets them up, but I'm sure it's out there somewhere.

I'll keep messin with the ht, I like your path much better than mine have ever really looked. I'll try different antennas, too. Thanks again. I love this APRS stuff - I think the ftm-400 might be in my future. Going to mess with one this weekend. :thumb:

04-10-2014, 07:05 AM
An interval of 10 min is pretty large. The FTM-350 defaults to 5 min for this setting. I seem to get about 25% of my packets through to the Internet, so if you're only sending them out every 10 minutes then your success rate might be one or two per hour. If you increase the rate then you might get half a dozen or so, which is sufficient IMHO.

I had a FTM-400 for a couple of months last year. When we sold the Tacoma didn't need the radio anymore. Too bad the timing didn't work out, I could have sold you that one! It's a nice radio, no doubt about it.

04-10-2014, 07:24 AM
thanks for the insight. I've changed the interval to tx more regularly. I had it in the car yesterday - (HT inside) and no beacon's got out. I'm going to attach my little SMA hershey kiss antenna to give that a try. Even at 5w, i think I should hit one or two times, don'cha think?