| |
PA2AGA > HDDIG 21.12.99 07:10l 207 Lines 6941 Bytes #-9643 (0) @ EU
BID : HD_99_321C
Read: DL6KCF GUEST
Subj: HamDigitalDigest 99/321C
Path: DB0AAB<DB0SL<DB0RGB<OE5XBL<OE3XSR<OE3XBS<OM0PBM<OK0PAB<HA5OB<HA3PG<
SV1AAW<EA7URC<PE0MAR<PI8VNW
Sent: 991221/0227Z @:PI8VNW.#ZH2.NLD.EU #:36059 [HvHolland] FBB7.00g $:HD_99_32
From: PA2AGA@PI8VNW.#ZH2.NLD.EU
To : HDDIG@EU
Received: from pa2aga by pi1hvh with SMTP
id AA26448 ; Tue, 21 Dec 99 00:35:41 UTC
Received: from pa2aga by pa2aga (NET/Mac 2.3.67/7.5.3) with SMTP
id AA00017285 ; Tue, 21 Dec 99 00:02:06 MET
Date: Mon, 20 Dec 99 23:57:38 MET
Message-Id: <hd_99_321C>
From: pa2aga
To: hd_broadcast@pa2aga
Subject: HamDigitalDigest 99/321C
X-BBS-Msg-Type: B
sure there
> is no ground connection to the metal box).
>
> But I think it is better to use the same ground as the rig for the
metal box
> (NOT the ground of the computer) since there will likely be less
RFI
> problems (as the ground or lack thereof of my lap top is not
great!)
>
> 73
>
> Rob
> **VA2FB**
>
> "George T. Baker" <w5yr@worldnet.att.net> wrote in message
> news:385B1C88.8954F49E@worldnet.att.net...
> > It doesn't matter where on the cable the transformer is inserted.
But, be
> > careful that you do not have any other connections between the
computer
> > and the rig. A common error/oversight is to use the transformers,
> > properly installed, and then add a PTT circuit controlled from a
serial
> > or parallel port. This automatically connects computer ground to
rig
> > ground and nullifies the action of the transformers. Another good
reason
> > to use VOX if your rig will support it with PSK31 or whatever.
> >
> > 72/73, George
> > Fairview, TX 30 mi NE Dallas in Collin county
> > Amateur Radio W5YR, in the 54th year and it just keeps getting
better!
> > R/C since 1964 - AMA 98452 RVing since 1972
> >
> >
> > Rob wrote:
> > >
> > > I have some ground loop problems between my rig and sound card.
I
> currently
> > > use two resistor networks to reduce the audio levels. (one for
the line
> from
> > > the sound card speaker out to the rig mic input and one for the
line
> from
> > > the rig aux audio out and the sound card mic input)
> > >
> > > I would like to use some audio isolation transformers on both
audio
> lines
> > > (I,e. the line from the sound card speaker out to the rig mic
input and
> the
> > > line from the rig aux audio out and the sound card mic input)
> > >
> > > Does it matter where I place the audio isolation transformers
on these
> two
> > > lines? e.g Can I place it on the side closer to the sound card
with the
> > > resistor network on the other side of the transformer closest
the rig??
> Or
> > > should it be vice versa?
> > >
> > > 73's
> > > Rob
>
>
>.
------------------------------
Date: 19 Dec 1999 00:46:34 GMT
From: haynes@alumni.uark.edu (Jim Haynes)
Subject: ground loops and audio isolation transformers
I have found it necessary in several situations that all happen to involve
Kenwood rigs to use an isolation transformer when feeding audio from a
TNC or computer sound card to the radio. I have used the little Radio Shack
output transformer 273-1380 since it also provides a voltage step-down.
In the Kenwood mic connector there are two separate grounds, one for the PTT
switch and one for the mic element. I run the transformer secondary to
the mic element pins only. This has cleared up the trouble every where I
have used it.
>.
------------------------------
Date: Fri, 17 Dec 1999 11:55:26 GMT
From: nomail@pe1chl.demon.nl (Rob Janssen)
Subject: Kenwood Control program that runs on Liunx AND Windows!!!!!
Jeff Pierce <piercej@preferred.com> wrote:
>I agree, I much prefer Linux to Windows. There is nothing "hidden" from
>you and it is really stable. (My Linux system at work ran over 9 months
>without a reboot until I had to power it down to move it).
>
>However, at this point in time Windows is the most widely used os,
>hopefully not for long :-). So, that is the os of choice for development
>dollars for control programs. One good thing is that outfits like Red
>Hat, Caldera, etc. are making Linux for easy to confgure and run.
Actually I don't think it is neccessary to convince people that they
should run Linux. That is something they have to decide themselves.
My system has been running Linux since 1992.
But, manufacturers should not try to convince me to run Windows95 either.
(by supporting only that system)
>I also am thinking about with the winter time coming to devise a
>proposal for a common radio command protocol. This could be used by the
>control program which talks to a server which translates to and from the
>actual radio.
That sounds like a good idea. Make sure you define your interface in
such a way that it can be run over a network. This is often forgotten
by API designers, making it necessary to add cumbersome redirector tricks
lateron... Just access it via a socket, and it can be used both locally
and over the network. A small set of functions packages the requests
in the application and ships them to the server that translates them
to the radio command. Does not matter if that shipping is locally in
the system (to another process) or via a network.
(of course you could use an existing RPC mechanism, but watch out for
portability problems)
That way, you can control the radio from another system in the house.
Developers of packet radio and other hamdradio applications should do
the same thing: my radio or modem isn't necessarily connected to the
same system I am sitting at. I might want to run an application in the
living room, controlling and accessing the radios in the shack.
Rob
--
+----------------------------------+--------------------------------------+
| Rob Janssen pe1chl@amsat.org | WWW: http://www.knoware.nl/users/rob |
| AMPRnet: rob@pe1chl.ampr.org | AX.25 BBS: PE1CHL@PI8WNO.#UTR.NLD.EU |
+----------------------------------+--------------------------------------+
>.
------------------------------
Date: Sat, 18 Dec 1999 19:17:31 -0600
From: "Steve Sampson" <ssampson@usa-site.net>
Subject: WinAPRS vs UI View??
When I downloaded APRS V2.4.0 it has an AGWPE interface, so when I used
it, it noted that I needed to upgrade my engine. I went to the AGW site, but
could not
find the new version. Then after your message I went and visited again. I
downloaded
the latest version, and it hasn't crashed yet. I did have a lot of trouble
getting it to
run right. Had to delete ports and reboot several times :-) Now we're
cooking. I can
run APRS and packet on the same dual-port TNC, or go use the sound card
interface.
Heck, I can even run APRS and UI-View together, and maintain the Internet
Server
feature of WinAPRS, and the GIF map features of UI-View :-)
Thanks for pointing out the new stuff.
Steve, K5OKC
Roger Barker wrote
>Have you got the latest version and the latest drivers? I've found V2000
>much more stable than previous versions - On my system it runs for days
>on end with three active ports without a problem.
>.
------------------------------
End of Ham-Digital Digest V99 #321
******************************
Both my XYL and myself wish you a Merry Christmas and
a very happy and prosperous New Year. Adam PA2AGA.
Read previous mail | Read next mail
| |
