Hello Stan,
?
Comment:
??? Yes, this sounds like it.... I assume this could be
done such that all stations could see each other's
traffic, or that only net control sees it if desired
that way by command/control personnel.?
DR> Without going to extra steps, NO, a classic connected
session is only between the net control and a specific
station.? Now with that said, it can be done using special
software of TNCs.? A TNC2 TNC with a 3rd party? X1J ROM has
the group chat feature called "talk" which would let
everyone see each others messages.? It works well but it
doesn't scale very well beyond say 10 stations.? Moving to a
pure software design, there is the Converse program for
Linux that does something similar to the X1J talk feature
(it's very similar to IRC if you know what that is).? Linpac
also has a similar feature built-in.
possible part of the vision, I
think, is that these nodes would be placed in an
automobile with a mag mount, and parked in a
functional location during the course of the event.?
So, if signal strength became an issue due to
distance, mountain in the way, or whatever, another
node could be deployed geographically in another
automobile to create another node to hop to in
between.? Periodic return to these vehicles would be
done as needed to ensure no dead batteries.
DR> Though this will work, you run the risk of stranding
a person's car with a dead battery.? For long operations, I
always recommend dedicated batteries for the radio setup.?
it might run out of battery but the car will always
restart.? To keep things all charged up, consider buying
something like a West Mountain PG40S to let the car charge
the radio battery but isolate it when the car isn't
running.? Check out my Kenwood D710 mobile installation for
more details on this approach if you're interested -
Comment:
??? I believe that there are one or two members of
the club that have these Kantronics TNC's, but I
don't know if they would be made available for this
purpose, but more importantly, I wouldn't want to be
counting on it.? So that leaves me with the laptop,
USB sound card and software to create these nodes.?
And if one of these other TNC's come available, so
much the better.
DR> Ok.. that's a sound starting point.
??? Ok, so scratch the Windows
version on a node.? The nodes would be handled by
the more technically savvy members anyway.? If a
laptop has some version of Windows on it, a disk
image can be captured and stored on an external usb
hard drive for later retrieval.? From there, the
laptop could be reimaged with a Linux system, and
set up as a node.? Then, if the owner wanted his
Windows image back on it, do so, and nothing lost.
DR> Depending on the age of the laptop, you can do one
better.? Boot Linux off a USB pendrive where it would run
completely off the USB pendrive and it never touches the
laptop's original HD.? All of your settings can be stored on
the pendrive too so the next time you boot off the USB
pendrive, it's exactly where you left off!? Check out say
for one example of this (this ISO a lot of other Ham Radio
software pre-installed.. including Direwolf, Linpac, etc.?
Very slick!? I also see he's working on version 20 so it
will have even newer versions of some of those programs,
etc.
??? I suspect all are possibilities, except maybe
the digipeater choice of the four you have
delineated.? And I am thinking this, because it
could possibly turn out that, at least some of these
nodes in vehicles mentioned in above comments, may
be run on handitalkies, and thus low power and
shorter reliable communication path.... thus needing
more nodes in between.? Bottom line, I think the
packet confirmation between nodes is the most
desireable, so that additional nodes may be added as
needed pretty easily.
DR> Yes, this is true but I encourage you to research the
term "hidden transmitter".? As you add more nodes to a
frequency, some stations won't be able to hear others but at
common points, the transmissions from the two station can
collide, causing excessive re transmits, etc.? While using
HTs will work, it's generally recommended to run radios with
10-25 watts for optimal performance.? Generally speaking,
mobile radios have better receiver performance in addition
to the added power.? Something to consider.
Comment:
??? Ok... maybe "dumb terminal" has more specific
meaning than I understand.? Maybe PuTTy Terminal??
Or a shell console on Linux.? So, your comment about
using some better software is probably where I need
to be looking.? Thanks!!
DR> Yes.. Putty would fall into the dumb terminal
context.? To give you a counter example, consider this
Linpac screen capture -
See that lower middle line with 1:WA6YNG-5 and then empty
fields for 2:, 3:, 4:, 5:, 6:, 7:, and 8:?? Each of those
numbers correspond to the F1, F2, F3, etc keys on your PC
keyboard and each one of those can be different CONNECTED
sessions to different stations. ? Alternatively, just one
session, say the F1 session can run the Converse chat room
that all other stations are connected to.? It's pretty
slick.
Comment:
Ok... noted.... that 99% figure is particularly
exciting!!
Yes.. Raspberry Pi and other single board computers (SBCs)
have really change things for projects like this.? There are
a LOT of compromises with using a small computer like this
(less reliable storage), slower I/O connectivity, etc. but
for packet radio and many other HAM radio projects, they are
perfect.
Ok.. I've probably choked you with way too much information
(I have a habit of doing that.. sorry).? It will be good
stuff for you to research and as specific questions on if
it's an interest to you.? Good luck with the project.
Btw.. this thread has been pretty off topic to Direwolf.? If
you want to ask packet specific questions, this is a good
place for it.? If you have more Raspberry Pi specific
questions, consider joining
which is a good place for that kind of thing (I'm on that
list too).
73
--David
KI6ZHD
