Is mobile HF APRS feasible for an overlanding vehicle?

[unusedusername]

Hello All,

I'm thinking I'd like to put together a HF APRS station in my Jeep.

I already have an IC-7100 installed in the Jeep with a screwdriver antenna. I am able to receive and "hear" packets on the 30m band.

It seems there is two competing standards for encoding packets on HF APRS: PSK63 APRS or AX.25 FSK APRS both at 300baud (vs 9600 baud AX.25 for 2meter APRS). I have not gotten far enough in to understand which HF format is "winning". Most of the desktop OS decoders are able to decode both formats.

The trick of the mobile install is that I don't have enough room in the vehicle to mount a laptop. I either need a matchbox-sized dedicated hardware box with a GPS that connects to the IC-7100, or some software that runs on iOS (or maybe Android) that is able to connect to the IC-7100.

The other trick is that the setup needs to be robust enough that it won't fall apart when going offroad over very bumpy roads.

Has anyone done anything like this?

 

[Airmapper]

Interesting project.

The only HF APRS rig I'm even remotely aware of is installed on a ship.....but it does remarkably well. It's on board a museum ship, call sign WW2LST and when it moves I like to watch it online as it navigates the inland river system. It gets out reliably, but given the vehicle it has more than enough room for a full on antenna and station.

 

[Frdmskr]

Absolutely but not Ax25. Use QPSK63 via APRSMessenger and any sound card interface or Robust Packet Radio using the SCS Tracker.


Sent from my iPhone using Tapatalk

 

[KE7JFF]

TinyTrak 3 and 4 supports HF APRS. I personally have good luck receiving 30 meter APRS, but never have tried TX yet.

 

[captadv]

I would look on eham.net. I would also look into pactor and winlink for position reporting. We used this when sailing and it's awesome, plus you get email and file retrieval like global weather data. If you won't have cellphone coverage is awesome.

Sent from my Nexus 6P using Tapatalk

 

[Hillbilly Heaven]

I will second the TinyTrak 3 or 4 with their GPS unit. I have use Byonics TinyTrak for years when 3 first came out. I have used them so NASA Rally course workers and sweep vehicles with outstanding results. They are small and once programmed are completely standalone.

With that said I have never used one on HF or even run HF packets. My only concern is you already have the HF rig mobile so you are probably using it for voice use. You will need to disable the Traker from transmitting when using the radio for something other than APRS. You don't want to change frequency and still have Traker active. It would connect to the Mini6Din jack on the back of the radio or the ACC jack. Disconnecting the PTT line will not stop the audio from the Traker it would be imposed with the mic audio. You need to disconnect PTT, Receive Audio, and Transmit Audio when you do anything other than APRS. Not familiar with the 7100 but there maybe a menu item to enable or disable Mini6Din or ACC. I am not for sure if USB D or Data will switch make it active. I know it will change filter settings. Read your manual you may find that unless you use USB D the Mini6Din is disabled.

 

[unusedusername]

Hillbilly Heaven:
Couldn't I run a remote power cut-off switch to the tracker?

 

[Hillbilly Heaven]

Blame it on not enough coffee. I was thinking too much on the other end not the front end. Yes you could just turn the power off. One catch to doing that is the GPS will do a cold start and maybe delayed in getting a position lock.
Think I better go brew another pot of coffee.

 

[binrat]

I'm just getting into it. Plan to use a TT3+ along with a hamstick, and my KX-2 for mobile. When stationary then I will use the KX-2 for QRP HF.

 

[kb1ejh]

I have been running HF APRS for a couple of years now both base and various mobiles. We could always use more base stations here in NA to improve coverage with the bands refuse to cooperate. Today I was able to pick up Finland, Italy, Switzerland, Germany, Ireland, Canada and of course US stations. The RPR network has been growing a bit here in NA but EU has been going strong with it. If you're pressed for space you can run a tracker remotely in the vehicle and have it switched if you only need it part time. I have been able to also run APRSDroid via BT to the SCS Dragons without issue. There is plenty of info to read up @ http://robust-packet.net/

 

[wirenut]

I recently got a Mobilinkd Bluetooth TNC. It's is about matchbook size. I connect it to my HT with a short cable. I use APRSdroid on my phone. It connects with bluetooth to the little TNC. This uses the phone's GPS, screen, keyboard, etc. It works pretty well on 2 meter APRS. I would think it would work on HF.

 

[gary in ohio]

so your going to tie up close to 2K worth of gear to send your position?
Seems there are lower cost options

 

[prerunner1982]

I recently got a Mobilinkd Bluetooth TNC. It's is about matchbook size. I connect it to my HT with a short cable. I use APRSdroid on my phone. It connects with bluetooth to the little TNC. This uses the phone's GPS, screen, keyboard, etc. It works pretty well on 2 meter APRS. I would think it would work on HF.

Except the Mobilinkd TNC does not do 300 baud needed for HF APRS. That would be too easy.....

 

[unusedusername]

so your going to tie up close to 2K worth of gear to send your position?
Seems there are lower cost options

I already have the HF radio installed, so no added cost there.

The SCS tracker is $350, which is honestly, more then I'd want to spend.
The Tiny Track4 is $180 with the cables and such, and I'd be OK with spending that much.

The question I have not been able to find yet: Where are the listening stations located that can receive packets from the TinyTrack? I found a map of them for robust-packet (that requires? the SCS tracker), but there really are not very many. There only seems to be only one gateway anywhere on the western United States, and unless I'm reading the status page incorrectly, as of 2/21/17 at 1:21pm that one gateway is down.

I don't have the space for another HF antenna at my house, so it isn't practical for me to add a gateway at my house. It would also cost me a couple of thousand for the parts

Maybe I'm better off just hooking up Winlink 2000 at my campsite and sending an email-via-HF when I get there and give up on going the "tracking while moving" route.

The point of all this is to send some sort of "I've arrived, all is well" message to my non-ham radio operator family members without needing to pay a monthly fee for a SPOT.

 

[Hillbilly Heaven]

http://www.aprs.net/vm/DOS/HF.HTM

http://aprsisce.wikidot.com/doc:frequencies