How do I test this thing?

So, the system has been confirmed to work, and I do some pretty extensive testing on my end to make sure all is well before I put the code live. Nonetheless as a user, you might want to send a message in to test, and that’s all good and well, but you need to do so without filling the spotting systems with junk data – fortunately, we’ve got you covered.

There are two ways to do this:

If you want to see your test spot:

For SOTA/WWFF/SIOTA – You’re out of luck. There is a test system in place but it’s not for public consumption.

For POTA: Simply send a message to the park “k-test” and it will send the SPOT into “pota.app” where you will be able to see your SPOT.

If you don’t want to see your test spot – but get a reply via APRS:

Send a message with “aptest” in the comment field. This will cause the system to simulate a SPOT to both PNP and POTA (if applicable) and reply. If you don’t get a response, refer to our section below on not getting responses.

I’m not getting responses to my commands, what’s happening?

FIRST AND FOREMOST: CHECK THE LIVE MESSAGES PAGE TO SEE IF APSPOT IS SENDING A RESPONSE.

A response looks like this:

If you see a line with YOUR CALLSIGN>APSPOT, your message is getting into RF.
If you see a line with APSPOT>YOUR CALLSIGN, APSPOT is sending a response.

If your message isn’t showing up on the Live Messages page:

• Did you address the message to “APSPOT”? If you didn’t address the message to the callsign “APSPOT” we won’t get the message, so we won’t know to respond.
• If your message didn’t show on the Live Messages page you may not have gotten into APRS-IS via an IGate. Check the digi path on your radio and/or try again when you’re in-range of a digi or an IGate. Alternatively, try APRS via HF

If your message AND the response are showing up on the Live Messages page:

• You may have gone in via a receive only IGate. See my section below about Receive Only IGates. In short, if you went into the network via a receive only IGate and you didn’t get heard by another Tx enabled IGate, you won’t get a response on RF. Your SPOT will however still get posted to the system.
• You may have gone in via a DIGI and the return path of the IGate might not be long enough. If your message has been digipeated via a couple of hops before it got to the IGate, it’s possible that even if Tx is enabled on that IGate that it’s just not sending the messages back with a long enough path to get back to you. Unfortunately this can happen, and the only fix is to contact your IGate operator and ask them to Tx messages with a longer path, for more digipeating. This does come with risks as it puts more noise on the RF channel however, best to speak with your IGate operator if this is happening.
• You may have sent the same usage command mote than once, and your IGate OR your radio may be flagging it as a duplicate message. For example if you send ”usage pota” in twice, you’ll get the same response from APSPOT twice. This can cause what your IGate or Radio may see as a duplicate, resulting in the response only being displayed the first time.

If your message is showing up on the Live Messages page, but not the APSPOT response:

• The system may be down. This is a highly experimental system that is actively in development – you may have caught us with our pants down while we’re updating the system. Trying again won’t hurt (the system does duplicate resolution, and will auto-restart if it crashes) to see if you get a response

Ok, so I’ve gone in via a RX Only IGate, how can I see if you got my message?

Check out the aprs.fi page for the APSPOT messages or check out our Live Messages page. You will be able to see if APSPOT got your command and if it responded.

Obviously this only works if you have internet access, in which case you can probably post your SPOT via another method – but props to you for still using APRS anyway!

A Word About Receive Only IGates:

Receive only IGates are designed to augment the APRS-IS system – which was originally intended to receive and map co-ordinate positions on https://aprs.fi/ – As the system expanded to include the sending of messages from point to point over RF, and ultimately point-to-point over RF and then APRS-IS (the internet) receive only IGate present a problem, that is, if your message/spot goes into APRS-IS via a receive only IGate, and no other transmit enabled IGate hears your message, then you will not get the confirmation messages back to your device. Likewise the “usage” and “spots” commands won’t work.

This can cause a problem when a message is sent from a HT for example – as the HT will send an “ack” request on the end of the message asking for an acknowledgement. If the HT does not receive an “ack” response, in most cases it will try once per minute for 5 minutes (at least that’s what my FT2DR does) until it eventually gives up. The APSPOT system would then receive 5 copies of your spot – but it won’t post 5 spots. There is inbuilt caching to ignore duplicates to handle this scenario.

In an ideal world, we would be able to get people who run RX-Only IGates to at the very least enable Tx of messages back onto RF from APRS-IS, so that end-to-end messaging still works, but unfortunately there are a LOT of IGate stations out there that are hooked into devices like RTL-SDR dongles which do not have Tx enabled. In my experience however a lot of Rx-Only IGates are configured that way because the documentation on how to limit your IGate to transmitting messages only is fairly scarce, and people are worried (or have been bitten) by enabling Tx on their IGate and flooding the RF network with irrelevant position and/or weather reports and blocking the local network with nonsensical SPAM traffic.

If you would like more information on how to enable Tx for messages-only on your Rx-Only IGate, please reach out to me. I’m happy to help you set your filters on your application to enable the relaying of messages back onto RF. Alternatively if you’re in an Rx-Only area and you’re unable to receive messages back from the system I would encourage you to work with your local IGate operator to see if it can be enabled. I’ve generally found that in this instance people are more than willing to come to the party and enable their IGates (if possible) to gate messages back onto RF.