I am really trying to get into APRS here in the Philippines.

I am absolutely delighted that Outernet has agreed to host the back channel for Outnet messages.

Basically a HAM can send a APRS short message addressed to Outnet and it will relay down from Space, on the 3 Outernet Inmarsat Satellites to virtually the entire world. Yep really groovy.

So haw can a Licensed Radio amateur use this Outnet receive option.

Send a APRS message through a VHF radio using a TNC/ Sound-card.

Send a APRS message through a HF Radio using TNC or sound-card. Freq 10.1473 MHz

Send a APRS message to the International Space station or APRS Satgates listening on the Freq 145.825

Send a APRS message through Open-source APRSDroid android software using a VHF or I-gateway. Link to free version of software here https://aprsdroid.org/download/

There is tonnes of Opensource software Xastir and YAAC are extremely comprehensive.

There is also lots of Open-source sound card software. Soundmodem and Direwolf I have tried and a little bit convoluted to get working but worth it in the end.

I look forward to hearing other people views in this forum.


Syed I am still not getting APRS messages coming down on 4F1 to the Philippines. About six days ago I got one set of message.0 but nothing since.

I have deleted my APRS folders etc.

I am trying hard to get APRS working and the receiving is very important to me.

Could you please double check you are transmitting APRS on 4F1.

Are you able to verify other users in the footprint of 4f1 are getting APRS messages?

I seem to be getting news and weather just fine.

I have flashed to the latest CHIP software and that does not seem to help.

If there is no solution to this, Can I beta test the new software to see if it sorts out my APRS problem.

144E should be identical to the other birds. I just asked Carl from from New Zealand. Have you sent any messages that are tagged OUTNET?

Thanks Syed. I look forward to finding out who is getting APRS messages.

Yes I have sent APRS messages tagged OUTNET. One day ago I sent one marked “Hi Syed and gang at Outernet”.

Can you give a description of how the current Carousel system works and distributes data to the 3 Inmarsat satellites.

I sent a message about an hour or so ago. I used the APRSDroid app on my phone. My thinking was that the app is directly connected to the Internet servers and so more likely to get injected into Outernet. If the ground based RF path for APRS is iffy at your location then its also likely that the messages you sent did not get through. It is an amateur network after all.

You’ll know its mine. Look for NI2O as the call and the date in ISO format as the message text.

Syed , has Carl from New Zealand been able to shed any light on 4F1 appearing to not send APRS messages every hour?

the “hi Syed and Gang” message was yours? I received that, though its been overwritten by now.

Fantstic I was wondering if it got through.

APRSdroid uplink and Outernet return. Outernet passes another milestone.

Meanwhile the message I send did not arrive.

Are you able to send a message per hour, just so we can make sure its getting received and then broadcast?

Not automatical like. I manually sent it via my APRSDroid app on my phone

I am still not receiving APRS messages but I can generate a OUTNET test APRS message each hour or so with the GMT Time included.

Seasalt KW4QB

Hi Syed I sent 8 APRS Messages from APRSDroid , roughly one hour apart.

I received one APRS message dump from Outernet L-Band service and they were all on it.

Please see below.

I think it is a successful test.

Fantastic! That means the system is working properly. What is the cheapest way to send these messages?

APRS messages can be sent by licensed ham radio operators by direct radio or direct internet connection.

If the remote users wish to use RADIO to send these APRS messages they will need to.

Become a Amateur radio Operator. I did my Ham exams through the Seven Seas Cruising Association sponsorship program. It was free to do.

Get a Amatuer Radio call sign issued.

Buy a 5-8 watt hand held VHF $50.00 Baofeng is fine.
Possibly you will need a simple home made Yagi antenna to increase range.

Get the free APRSdroid app for android phone off the APRSdroid website.

Connect the android earphone out cable into the Handheld radio microphone in connector.

Tune Radio to the desired APRS frequency.

Turn on VOX (Voice activation, triggering of “press to talk button”.)

Create APRS message with OUTNET as the address in APRSdroid and hit send.

It will then send a modulated sound to the radio which will broadcast it out.

APRS messages have no acknowledgment or error correction.

Hopefully a APRS I-Gate or digi-repeater on the ground or in space will receive it and get it into the APRS network and forward it to OUTNET.

Thats it.

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Is there anything cheaper than the Baofeng?

If the Outernet user only needs to send a APRS message to space or the next terrestrial APRS receiver or I-Gate.

They do not need to receive a acknowledgement that the message has been received, for the message to go through to OUTNET.

In other words the user only needs to send the message a few times as the satellite goes over and it has a high probability of getting through.

In other words the user only needs a VHF 145.825 TRANSMIT device to send APRS messages.

There are $25 Baofeng radios that would do the job.

I guess you could make a APRS transmit only RTL Type dongle but it would be hard to beat Baofeng pricing and you would run into a heap of regulatory requirements in order to sell a transmitter.

The Satellite APRS signal is 145.825.

Amateur Radio equipment on the International Space Station was enabled for APRS digipeating on 145.825 using the path of ‘VIA ARISS’.

One thing I am thinking is maybe you can some how use the ISM Industrial frequencies that WIFI etc use.

" The industrial, scientific and medical (ISM) radio bands are radio bands (portions of the radio spectrum) reserved internationally for the use of radio frequency (RF) energy for industrial, scientific and medical purposes other than telecommunications"

Don’t forget that you’ll also need a modem of some sort for the radio path too. Simply owning a radio does not get you into the APRS network. You’ll need an 1200bd AX.25 compatible modem and some way of speaking to it. These days there are many ways to accomplish this. Software modems, Arduino’s, PIC’s etc.

Here’s a youtube video https://www.youtube.com/watch?v=8-9_8HVkvgc

It demonstrates a cheap way to get onto APRS using the APRSDroid application and $30 VHF ham radio. The modem tones are generated using the sound abilities of the Android phone. It’ll be enough to get into the RF network. Maybe not enough to get into the wired network. APRSDroid can however, inject messages directly to the APRS Internet servers.

Understand that this is an amateur network. It operates by the graces of hams with some spare cash. Nothing is gauranteed. You may send messages and they may or may not get through. The RF network is full of huge hole as can be seen here on my last 4 days driving around NJ, PA and DE http://aprs.fi/#!mt=roadmap&z=11&call=a%2FNI2O-1&timerange=345600&tail=345600 Even in the most populated areas the network is very Swiss cheese like.

I would point out again that a ham radio licence is required to access this system.

OK, so now I know why my message did not arrive. APRSDroid only sends messages when you are in tracking mode. DUH!!

OK. That worked. I currently see my 3 messages.

What’s the “ppersist” setting on APRS massages? I sent mine well before midnight last night and they are still showing up on the download 15 hours later.