[amsat-bb] Help on ISS Packet Needed

Alan wa4sca at gmail.com
Sat Feb 28 12:26:17 UTC 2015


You have gotten some good references.  Aside from any other issues, the Flex has a significant amount
of latency.  That is, it takes a noticeable amount of time for the software to process that audio and
send it.  How much depends on your computer, buffer settings, etc.  We are talking in the dozens to a
couple of hundred milliseconds.  The result is that the last part of the packet can be cut off.
Fortunately there is a parameter in the modem programs called TXTail which effectively extends the
amount of time the rig is keyed.  After you get the rest sorted out, change that to something like 500
ms, initially, and then back it off.  See the individual programs for details.



<-----Original Message-----
<From: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org] On Behalf Of Richard Lawn
<Sent: Friday, February 27, 2015 3:09 PM
<To: Amsat BB
<Subject: [amsat-bb] Help on ISS Packet Needed
<Years ago I used to understand packet and actually used to work the store
<and forward orbiting BBS satellites we had access to. Things have changed
<radically in my station setup and I'm baffled as to how to get things to
<work together. I'm sure I could re-learn this if I knew what to read that
<would walk me through things and refresh my memory. Here is my
<software/hardware setup:
<Flex5000A V/U
<I use virtual serial and audio ports and the computer's sound card.
<I have installed: UISS, AGWPE, Packet Engine Pro, UZ7HO Term and SoundModem
<Using AGWPE and UISS I am receiving packet station son 144.390 no problem.
<Past that I'm stumped on how to get the transmit side going and what
<protocols are used for connecting to anything let along ISS.
<Any help would be appreciated and for that matter just point me to
<something I can read and come away understanding this. It's days like this
<that I long for hardware TNC's and radios with knobs! :)
<Although I'd still probably have trouble as I was a lot younger when I got
<all this to work years ago.
<Rick, W2JAZ
<Sent via AMSAT-BB at amsat.org. AMSAT-NA makes this open forum available
<to all interested persons worldwide without requiring membership. Opinions expressed
<are solely those of the author, and do not reflect the official views of AMSAT-NA.
<Not an AMSAT-NA member? Join now to support the amateur satellite program!
<Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb

More information about the AMSAT-BB mailing list