Saturday 10 March 2018

APRS Messenger for HF - is anybody there?

Thanks to my blogger colleague Bas, in the Netherlands, I have been getting to grips with APRS Messenger software for HF recently.

This looks like an interesting new addition to the range of activities with HF radio.  But I am not really sure what the software is actually for.  I guess it is somehow 'disaster'-related, but I am not a US-style Prepper, and don't expect ham radio will save us from annihilation if Kim Jog Un presses his little red button.  There will, after all, be nobody left to communicate with.  Also, nuclear detonations are known to severely disrupt the ionosphere to the point where propagation will be, at best, tough.

This is what N8PJ, who runs PACTOR.com, has to say about emcomms:

"The continued claims PACTOR-4 serves ECOMM (Emergency Communcations) is a ruse, a falsehood. There are so many alternate 'free' commerical communications paths available that it renders the argument that "Ham Radio is a viable alternative for emergency communication" a joke. Much more reliable communications alternative are available today."
 
Never mind.  I still have my rig...

For now, the biggest problem with APRS Messenger is that it seems rather deaf.  I have seen a few signals on the waterfall, but over three days or so, I have only seen the software decode two stations - OH8STN (once) and K1CKK multiple times.  Including the US station, this seems to be good going, compared to many, who don't seem to be decoding much at all.

The problem seems common to most.  A discussion group tells of the troubles thus far with this, admittedly experimental and under-development program.  Another blogger also has tales of woe.

UPDATE.

I've uninstalled the software, unsubscribed from the related Yahoo! group, and left the author to sort the program out, which he now admits is "not 100%".  

From his postings online, he seems to expect everyone's rig will be so well frequency calibrated that they might match a physical standards laboratory's levels.  My rig is +4Hz out on 10MHz, +2Hz out when averaged across all bands.

Any mode that, unlike the plethora others, demands absolute accuracy from what are, in the end, consumer-level electronics, is missing the point and doomed to failure - which is what Messenger appears to be undergoing right now. 

And why, pray tell, would I bother wasting time on a mode and software that has little purpose and doesn't anyway work, when I can turn to countless other modes that do?

3 comments:

PE4BAS, Bas said...

Yep, there are problems. But isn't it fun? If everything works as advertised the fun was over in a few days....73, Bas

PE4BAS, Bas said...

Oh, the other blogger....that story is familiar to me:
https://pe4bas.blogspot.nl/2018/03/aprs-on-hf-with-aprs-messenger-weekend.html

Nick B. said...

I played around with this a while back but I haven't tried the reecent MFSK-4 update. I came to similar conclusions. What nobody seems to mention is that the HF modem implementation uses MMVARI with multiple modems configured so if Chris were to share the method Messenger uses to create and verify the checksum then the same modes could be implemented with FLdigi or other software. It's just unfortunate that the Visual Basic interface is so clunky. I think it's original purpose was to overcome the deficiencies of HF Packet APRS at a lower cost than buying a SCS modem for Robust Packet.