Packet Radio -- Get a room!

The IRC virtual APRS packet radio allows you to dynamically create packet radio chat rooms. Send a single message to IRC, and every radio in the room will get it.
Example -- Send these messages to callsign "IRC":
/join #lounge
message text to your only channel
/join #otherchannel
#otherchannel message text to other channel
#lounge message to lounge again
/leave #lounge
/leave #otherchannel
(do not use /msg -- my mistake)
This is largely beta-test software implemented by WB4BOR. Please be gentle. Track ongoing channel traffic at aprs-irc.hemna.com/
digipi.org
/ km6lyw # Patrons get the DigiPi SD card image!

[@ghostmandka5498]

Awesome stuff! And the bumper music still rocks!

[@hawkeyeCH53E]

Nice PRS Craig

[@jmcgregor316]

Nice PRS.

[@JonGlauser]

how much different would this be from ANSRVR or CQSRVR? Seems very similar to me

[@stigtheghost]

APRS #Thursday!!

[@hardwired3640]

Any concerns about congestion on 144.390?

[@KM6LYW]

I'm guessing you haven't experienced APRS Thursday yet :) . the frequency is shockingly resilient, single collision domain, 250ms for an ack, wait-until-clear, re-transmit. It's really the first implementation of TCP/IP, based on AX.25.

[@hardwired3640]

@@KM6LYW you’re correct. I’m in a sparse rural area. I just don’t want to make the digipeater owners angry by clogging the system in our area. Just wondering because I don’t want to cause any issues.

[@ThomasHart59]

@@hardwired3640, I think, in my case, here in the greater Los Angeles area, we saw just what you were concerned about... Specifically IRC numbered ACK packets being digipeated continuously by high level digipeaters. This would definitely result in a low power APRS station not getting its position out and onto the IS.

[@ThomasHart59]

@@KM6LYW , I think, in my case, here in the greater Los Angeles area, we saw just what @Hardwired3640 was concerned about... Specifically IRC numbered ACK packets being digipeated continuously by high level digipeaters. This would definitely result in a low power APRS station not getting its position out and onto the IS.

[@hardwired3640]

I would love to be able to use this chat with vara fm on a different dedicated vhf frequency, possibly 6m fm

[@hawkeyeCH53E]

Craig, any ideas why winlink never adopted APRS technology? Is it too slow, perhaps in case the internet goes down??

[@iliestefancostin]

Winlink work on APRS. But use some short commands witch is not easy to remember. Destination is WINLNK-1. Login password is first 3 (randomly required by server) letter form your password + another 3 letter you chose.

[@KM6LYW]

Great question - Winlink uses AX.25 networking on VHF and APRS is a subset of the AX.25 protocol. They're very similar but ultimately exclusive. Checkout WLNK-1 to do basic winlink email over APRS. winlink.org/APRSLink -- extra credit: send winlink email through the ISS APRS digipeater! :)

[@iliestefancostin]

Hello Craig. In my situation, APRS Digipeater + APRS Webchat NEVER work togheter. Once i turn on APRS Webchat, APRS Digipeater switch to APRS iGate TNC, witch have another problem. Its receive only. Radio dont transmit on Igate mode. What shoud i do?

[@KM6LYW]

yah, webchat needs to depend on one or the other, if you want Webchat to use the Digipeater tnc, run "sudo remount" then edit /etc/systemd/system/webchat.service and change the Requires line from tnc to digipeater. Then Webchat will fire up the Digipeater instead of TNC.

[@iliestefancostin]

@@KM6LYW Thanks! Done!

[@W4TRI]

Ok I for one would not mind tossing in a few bucks to make a "hardened" RF IRC server network. This has to be set up using one PC as the weakest link to relay packets to/from IRC. Someone please prove me wrong because 30 ears in Telecom tells me some stuff is dependent on a shoestring.

[@WalterBoring]

You mean an actual IRC relay? Man could quickly overcome the aprs network. It's doable. The "IRC" callsign is it's own thing not connected to any irc network at all. It just creates it's own irc like server with channels that you can join and have a group chat with others.

[@W4TRI]

@@WalterBoring How is this virtual channels created and controlled? I'm looking for the central point of failure not to criticize but to advocate it be strengthened. What's under the hood here?

[@KM6LYW]

Right, this isn't an IRCd server, it's an entirely new implementation for ham radio that looks/feels like IRCd. Real IRC would be overwhelming on the channel imho. If you want IRCd on radio, try IP over AX.25, it works! Just a lot of overhead.

[@W4TRI]

@@KM6LYW Craig nowhere above did I say it was. I do know that the virtual callsign is the key and that is controlled by one program on one server on the internet. Your packets were getting out to a Igate and to that server. I was trying to lead a charge to help it be expanded in the future so when this one server goes down we might still have the service.

[@KM6LYW]

@@W4TRI Sweet, yah, we could make something resilient or fault tolerant with geographic diversity and fail-over. Kinda like the APRS network itself.

[@ThomasHart59]

This thing is contaminating the APRS frequency with a ridiculous number of RF retransmitted ACKs. Even though I am not shown as connected, I've had to disable my Igate because of the ACKs from "IRC" that are continuous. This needs to be shut down until the issues are worked out.

[@Pahrump]

Move on sad ham @ThomasHart59

[@ThomasHart59]

@@Pahrump Hi Pahrump. I'm not sure why you feel the need to be disrespectful. I operate a high level Igate, and woke up this morning to continuous ACKs from IRC being retransmitted out in the LA area every couple of seconds. This represents a serious congestion problem on the APRS frequency. Pointing it out is not being a "sad ham", I actually like the concept, and joined the "lounge" last night, but we can't have something that is not quite right doing what this was doing. Thanks for your comment though, have a nice day!

[@WalterBoring]

After looking at your logs of your igate, it's clearly re-encapsulating packets and resending them multiple times. This is not a problem with the IRC service at all.

[@ThomasHart59]

@@WalterBoring Right, as I allowed in my email to you Walt, this may be an issue in how existing software deals with these ACKs. Obviously the way IRC distributes these causes a problem and represents a departure from standard expected behavior, I think Lynn explained it far better than I can. I'm certain you can see how digipeaters in a geographic area continually repeating ACK packets over and over again might represent a problem? And that this problem simply doesn't exist outside of the context of IRC? Regardless of how "correct" you are, if the behavior of IRC brings down the APRS network, it doesn't really matter who is right, does it?

[@WalterBoring]

@@ThomasHart59 Sending an ack packet is not a "departure from standard expected behavior". It's literally in the APRS spec.

[@KH07734]

Eh, The guitar is a bit much dude.....Just saying....

[@KM6LYW]

Yes, but every youtube Must... have... bumper.. music! for some reason. :)