headers
Mike Markowski | 1 May 2003 20:00
Picon
Favicon

Pc/rig interface for packet

Thanks, everyone, for your helpful responses of a couple weeks ago.
I've now got my rig talking to my laptop via hamlib - I love xlog's
use of hamlib!

I had other things occupying time for the last couple weeks but
now want to get back to getting a packet radio set-up up &
running.  The user mode soundmodem & kernel (2.4.20) w/mkiss
support is now compiled, though I haven't finished going through
the HOWTO to get everything else set up - that AX.25 HOWTO seems
to go on and on...  :-o  I haven't bothered finishing it yet
because I still have to make a cable, which brings me to my
question.

For the rig/pc cable do you have opinions of the two choices I'm
aware of:

   * Use a simple idea like
     http://www.baycom.org/~tom/pcf/ptt_circ/ptt.html

   * Buy the Rascal kit (US $20) at
     http://www.packetradio.com/psk31.html

Would electrically isolating the Tx/Rx/PTT signals like in the Rascal
kit make a significant difference?  I read that the isolation is
important if you want to use packet on HF.

	Thanks!
	Mike   AB3AP
-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
(Continue reading)

Permalink | Reply | 2 comments |
headers
Curt Mills, WE7U | 1 May 2003 20:05

Re: Pc/rig interface for packet

On Thu, 1 May 2003, Mike Markowski wrote:

> now want to get back to getting a packet radio set-up up &
> running.  The user mode soundmodem & kernel (2.4.20) w/mkiss
> support is now compiled, though I haven't finished going through
> the HOWTO to get everything else set up - that AX.25 HOWTO seems
> to go on and on...  :-o

If you're interested in APRS on Linux, the Xastir package supports
serial port KISS and the soundmodem program supports a KISS mode
where it looks like a serial KISS device.  Connect the two together
and you're up and running without having to set up AX.25 kernel
networking.  Just another option.

If you're interested in other kinds of packet, Xastir won't help you
there.

--

-- 
Curt Mills, WE7U                    hacker_NO_SPAM_ <at> tc.fluke.com
Senior Methods Engineer/SysAdmin
"Lotto:    A tax on people who are bad at math!"
"Windows:  Microsoft's tax on computer illiterates!" -- WE7U
"The world DOES revolve around me:  I picked the coordinate system!"

-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
the body of a message to majordomo <at> vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
(Continue reading)

Permalink | Reply | 0 comments |
headers
BobDonnell | 1 May 2003 22:38

RE: Pc/rig interface for packet

Hi Mike,

My two cents worth:

I prefer the Baycom modem approach, if where you're headed is the
1200-baud packet world.

My thinking:

Baycom needs a single cable connection to your PC.  The DB9 or DB25
connector is rugged, has a reasonably high resistance to being pulled
out of the connector, and can be screwed down, if needed.  This cable
connection carries only data.  The modem 'steals' operating power from
the serial data port.  This might not work well with some laptops, but
generally works fine for desktop PC's.  Many radios provide receive
audio on the microphone connector, and some even provide that audio at a
fixed level, so the position of the volume control is not important.
Some even provide unsquelched audio, which is even better.  Even better
is if your radio has a data connector, that definitely provides the
connections you need, all on one connector.  You can create a fairly
short radio cable, reducing your susceptibility to RF fields, and all of
the audio and PTT functions are handled at the modem, reducing your
likelihood of a ground loop affecting transmitted audio.  You'd see an
AC ground loop if the chassis of your radio is at a significantly
different potential than the PC.  This should be solved pretty easily by
running a substantial ground wire between the PC case and the radio
case.

By contrast, using a soundcard interface requires 3 cables from the PC -
one for audio it, one for audio out, and one connected to either a
(Continue reading)

Permalink | Reply | 2 comments |
headers
Tomi Manninen | 2 May 2003 11:46
Picon
Picon

RE: Pc/rig interface for packet

On Thu, 1 May 2003 BobDonnell <at> arkalmus.com wrote:

> I prefer the Baycom modem approach, if where you're headed is the
> 1200-baud packet world.

Mike wasn't talking about BayCom modems. He was asking whether the PTT 
circuit shown at that baycom address was ok...

I have used a homemade interface where the PTT connection is similar to 
the "Serial Port Solution" on that page. Also I have no isolating 
transformers in the audio paths. I have had no problems with the setup 
even though my HF antenna (a random wire) is only a few meters away from 
the rig/pc.

However this is something everyone seems to have his/her own opinion and
they're all probably right. There are so many variables in a typical
station setup that you will have to try to see if _you_ need DC isolation
or not.

I don't know the Rascal kit interface but to me $20 seems cheap. Just 
buing a decent enclosure for a homemade project can easily be more 
expensive...

--

-- 
Tomi Manninen           Internet:  oh2bns <at> sral.fi
OH2BNS                  AX.25:     oh2bns <at> oh2rbi.fin.eu
KP20ME04                Amprnet:   oh2bns <at> oh2rbi.ampr.org

-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
(Continue reading)

Permalink | Reply | 1 comment |
headers
Sriram Chadalavada | 2 May 2003 17:29
Picon
Favicon

TNC Software emulator - talk with KISS interface

Hello everyone,
  I am looking for software (KISS-based)TNC emulators
that can run on Redhat 7.3 configured with AX.25
support.
Currently, I have installed KISS interfaces on two
Linux boxes and made them talk. But our project
(KUTESAT) needs emulation of an AX.25 link between two
systems ie a KISS interface on host talking to a sw
TNC which in turn communicates with its counterpart on
the other machine.
               I looked up on the web and found tfkiss
rpm which works on Suse. Can this be used on Redhat
7.3 too (installation as rpm or from source)? If so,
is it possible to make it work with the KISS
interfaces described above (created by using
kissattach command)?
                                       Cheers,
                                       Sriram

__________________________________
Do you Yahoo!?
The New Yahoo! Search - Faster. Easier. Bingo.
http://search.yahoo.com
-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
the body of a message to majordomo <at> vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Permalink | Reply | 1 comment |
headers
Tomi Manninen | 2 May 2003 18:30
Picon
Picon

Re: TNC Software emulator - talk with KISS interface

On Fri, 2 May 2003, Sriram Chadalavada wrote:

>   I am looking for software (KISS-based)TNC emulators
> that can run on Redhat 7.3 configured with AX.25
> support.
> Currently, I have installed KISS interfaces on two
> Linux boxes and made them talk. But our project
> (KUTESAT) needs emulation of an AX.25 link between two
> systems ie a KISS interface on host talking to a sw
> TNC which in turn communicates with its counterpart on
> the other machine.

Hmm... What do you mean by an AX.25 link? What kind of signals do you need 
for the link?

The KISS "protocol" is simply a very simple encapsulation of AX.25 frames 
over serial lines. When using KISS mode, a TNC actually hands over all the 
AX.25 protocol handling to the host PC. The TNC is left only with HDLC 
processing (bit stuffing and framing), CRC checking and the actual 
modulation/demodulation.

I would say that two computers talking KISS to each other, actually have
an AX.25 link.

But maybe you need something else? Syncronous HDLC signals maybe?

>                I looked up on the web and found tfkiss
> rpm which works on Suse. Can this be used on Redhat
> 7.3 too (installation as rpm or from source)? If so,
> is it possible to make it work with the KISS
(Continue reading)

Permalink | Reply | 0 comments |
headers
malcolm davies | 3 May 2003 07:34

Linux Soundmodem help required

Hi,

HAs anybody out there got the User space soundmodem programme operational

I am currently attempting to run this programme but keep getting error
messages relating to keying

dev '/dev/ttyS0' neither a parport or serport
cannot start PTT output

I have confirmed that the port exists and works by connecting a modem which
installs and works ok (I did deinstall afterwards)

The sound side of things works ok as does the sm0 port as I am able to use
call and ping and get packet from the speaker.

where next

regards

malcolmd

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.476 / Virus Database: 273 - Release Date: 4/24/2003

-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
the body of a message to majordomo <at> vger.kernel.org
(Continue reading)

Permalink | Reply | 1 comment |
headers
Curt Mills, WE7U | 3 May 2003 01:09

Re: Linux Soundmodem help required

On Fri, 2 May 2003, malcolm davies wrote:

> dev '/dev/ttyS0' neither a parport or serport
> cannot start PTT output

Check permissions to see if a normal user can write to that port.
You can either change permissions on the port or add your user to
the group that owns that port.

Try the /dev/cua0 port instead.  That's another way to access the
same port.

--

-- 
Curt Mills, WE7U                    hacker_NO_SPAM_ <at> tc.fluke.com
Senior Methods Engineer/SysAdmin
"Lotto:    A tax on people who are bad at math!"
"Windows:  Microsoft's tax on computer illiterates!" -- WE7U
"The world DOES revolve around me:  I picked the coordinate system!"

-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
the body of a message to majordomo <at> vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Permalink | Reply | 0 comments |
headers
Paul Lewis | 3 May 2003 18:38
Picon
Picon

node 0.3.1 connect_to: connect: No buffer space available

Hello Readers

Anyone got pointers to this error.

Internet search has not come up with an answer.
Do I have control over the buffer referred to?

Occurred since I added encap routes to my server's gateway

T 44.131.10.55
GB7CR:CRNODE CRCHAT:GB7CIP-5 connect_to: connect: No buffer space 
available

Paul g4apl

--

-- 
paul <at> skywaves.demon.co.uk
-
To unsubscribe from this list: send the line "unsubscribe linux-hams" in
the body of a message to majordomo <at> vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Permalink | Reply | 1 comment |
headers
Paul Lewis | 4 May 2003 09:17
Picon
Picon

Re: node 0.3.1 connect_to: connect: No buffer space available

Hi Readers

Still tracking this down, not a node error after searching around the 
Internet for clues.  Seems to be a general error message.

Eventually located the following in the kernel log in the early hours..

Lots of these messages

Now to find out how many 'neighbour' are allowed. may be related to the 
number of active interfaces I have operational on my system

May  3 20:29:52 gb7cip kernel: neighbour table overflow
May  3 20:29:57 gb7cip kernel: neighbour table overflow
May  3 20:30:02 gb7cip kernel: neighbour table overflow
May  3 20:30:07 gb7cip kernel: neighbour table overflow
May  3 20:30:12 gb7cip kernel: neighbour table overflow
May  3 20:30:17 gb7cip kernel: neighbour table overflow
May  3 20:30:22 gb7cip kernel: neighbour table overflow
Paul

In message <BodzvMB$B$s+Ewys <at> skywaves.demon.co.uk>, Paul Lewis 
<paul <at> skywaves.demon.co.uk> writes
>Hello Readers
>
>Anyone got pointers to this error.
>
>Internet search has not come up with an answer.
>Do I have control over the buffer referred to?
>
(Continue reading)

Permalink | Reply | 0 comments |

Gmane