Fwd: APRS Messenger now has APRS over PSK-63

Bill V WA7NWP wa7nwp at gmail.com
Sun Feb 28 18:12:06 PST 2010

This is way cool...

APRS on HF no longer needs 300 baud packet...

---------- Forwarded message ----------
From: Stephen H. Smith <wa8lmf2 at aol.com>
Date: Sun, Feb 28, 2010 at 5:42 PM
Subject: Re: [aprssig] APRS Messenger now has APRS over PSK-63
To: TAPR APRS Mailing List <aprssig at tapr.org>

On 2/28/2010 2:46 PM, Chris Moulding wrote:

Following Stephen's explanation I've just uploaded a 1800 Hz version
of APRS Messenger v2.33 to the webpage:


The other audio tones, 700, 1300 and 2100 Hz are also available.

APRS over PSK-63 activity is increasing daily in Europe and the US.
It's a quick and cheap (free) way of getting on HF APRS. The amount of
feedback I'm getting on the program is helping development. It already
has a TCP/IP link to export HF APRS packets to map display on
APRSISCE/32 and RadioMobile,  soundcard selection, selectable HF
beacon rates, VHF / HF stations heard listboxes and a lot of
improvements over the initial version. Over the next few weeks I'll
add GPS input to allow mobile HF tracking over PSK-63.


This is way cool!

I have just finished experimenting with using the TCP/IP port 8063 to
link to other APRS applications.  I can now confirm that the local
port 8063 works with UIview, APRSplus and APRSpoint.

In the old days of the G4IDE PSK31 Server for UIview, one used the PSK
Server's IP connection just as through it was an Internet APRS server.
 You simply set up your APRS application's server config to log into
"localhost:portnumber" instead of a "real" .  ("localhost" a.k.a.
"" is a "magic" IP address that always means your own
computer rather than another one on a network.)

I threw together a test setup consisting of two laptops with their
sound systems cross-connected with 3.5mm patch cords.  I am running
the 1300 Hz version of the latest APRS Messenger (getting ready to
deploy it in a setup using KAM tones on 10.151.000 LSB) on both
machines.    In turn, I set the main APRS TCP/IP server login of
UIview, APRSplus and APRSpoint to "" and have
sent/received messages from all three.

However the port 8063 server apparently can only accept one connection
at a time. (The local server in UIview will accept multiple clients at
once.)  Solution:  I have UIview's main "APRS Server Setup" connected
to APRS Messenger.  In turn, UIview's "local server" is re-sharing the
data with both APRSpoint and APRSplus.    All three now receive
messages sent from the other laptop at the same time.

I assume that once APRS Messenger gains the GPS input and capability
to send posits, that this will work to put APRS posits on the map in
any (or all) of these programs.    To make the most of the slow PSK
transmission rate, I would strongly suggest that APRS Messenger use
the highly-compressed MIc-E transmission format since it is about
ONE-THIRD the length of a plain-text APRS posit. The downside is that
it is not human-readable, although ALL APRS mapping applications can
decode it.

As I write this message (at about 5:40 PM Pacific Time here in
Pasadena, California), I can actually hear faint PSK carriers
underneath (pitch-wise) the conventional AX25 packet tones on my TS-50
monitoring 30M.    This will be a REAL challenge but may well
demonstrate the superioriority of PSK63 over FSK packet, since my
local noise level (from a leaking cable TV trunk line) is absolutely
horrendous -- around S9.

Gotta go and connect one of the laptops to my off-air monitoring system........


Stephen H. Smith    wa8lmf (at) aol.com
EchoLink Node:      WA8LMF  or 14400    [Think bottom of the 2M band]
Skype:        WA8LMF
Home Page:          http://wa8lmf.net

NEW!    Universal HF/VHF/UHF Antenna Mounting System

"APRS 101"  Explanation of APRS Path Selection & Digipeating

Updated "Rev H" APRS            http://wa8lmf.net/aprs
Symbols Set for UI-View,
UIpoint and APRSplus:

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