Re: Old TNC's

Greg D

Hi James,

So, only partly.  The modes I was referring to were "traditional" packet radio, not APRS.  APRS was certainly crafted without regards to the OSI model's 7 layer Cake, but in spite of that it's held up remarkably well and still serves a useful purpose.

On the other hand, the evolution of the Packet BBS network largely stalled.  There are still a few mailboxes on the air within reach of my home station, but they are hardly swamped.  The 2400 bps modem that I have was never widely adopted (I may have the only one left), and the jump to 9600 bps seems to have been the victim of a combination of regulatory bandwidth limitations and the widespread adoption of the Internet's  NNTP servers.  There are a few 9600 networks around, but not many, at least not around here.

I would argue that both developments - the success of APRS and the relegation of other packet modes to a niche - are as they should be.  It's about meeting a need, and being flexible to evolve as that need evolves, not about architecture for architecture's sake.  I think that having "old TNCs" still in productive service in parallel with Raspberry Pi's and Direwolf is a testament that the Ham community got something right.  I have both running here in the shack.  The subject MFJ TNC is hooked to my "home server" (a Linux PC that's always on) as an APRSIS32 APRS iGate, and a Raspberry Pi with Direwolf that is cabled to the main shack radios for the other packet stuff (Winlink, mostly), along with the Joe Taylor HF modes. 

The Pi and shack radios are things I can run from battery backup power, when all else has failed or been turned off (I'm in "Public Safety Power Shutoff territory here), for remote email and such.  When not doing so, I use it to check into a UI Packet net every Sunday.  Why not?  People still use Morse Code for much the same reasons.

Greg  KO6TH

Such is progress.

James Ewen wrote:

“but such is progress...“

You are of course being disingenuous here, right?

APRS is a protocol stacked on top of 1980’s hardware, using chewing gum and baling wire. 

Bob’s baby has squeezed a lot of life out of 40 year old equipment, there’s no denying that, but to think this is progress... 

I guess the automobile industry in Cuba is also making great progress as well. 

I love APRS, it is probably my favourite part of amateur radio, but is anyone here interested in investing in actually making progress? Progress would mean moving to newer hardware, hardware that would remove the limits of 1200 baud, probably something with an SDR base, and a whole new way of defining the protocols we use. Something designed from the ground up, not something that uses clever tricks to make old hardware work in a new way. 

We are kind of stuck in a rut today because there’s so much old hardware out there that we don’t want to throw out. But that old hardware handcuffs us to 1200 baud. 

I’m not going to be the one to lead the charge, but there are some really smart cookies out there that are building some cutting edge hardware that might be a base for the next big thing to take over for APRS. For that to succeed, we need to be willing to let the old hardware go, and embrace new technologies. 

It’s up to all of us to be willing to help the next big thing become that big thing. 


On Sun, Nov 8, 2020 at 3:38 PM Greg D <ko6th.greg@...> wrote:
Yep.  MFJ-1278T in use here.  Seems a waste to run it in KISS-1200 mode, given it's huge mailbox and added 2400bps modem, but such is progress...

Greg  KO6TH

Brian Webster via wrote:

They work great for APRS, any program that needs a kiss TNC. I still run my daily. The only time it’s not ideal is when you need the TNC on a node site that needs special firmware in the eprom. Only a few TNC’s that are TAPR 2 clones (paccomm, MFJ 1270 series) are suitable for those chips. Normal packet users can use just about any type of TNC. The PK88 uses the same command set as a TNC2.


Brian N2KGC


From: [] On Behalf Of Bob & Jane
Sent: Sunday, November 8, 2020 4:03 PM
Subject: [APRSISCE] Old TNC's


Where does an AES PK-88 fit into this list?


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