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PA2AGA > HDDIG 25.09.99 03:26l 217 Lines 7894 Bytes #-9766 (0) @ EU
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Subject: HamDigitalDigest 99/239H
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Gary Coffman <ke4zv@bellsouth.net> wrote in message
news:1bfnNxWU0Z2GhBJY+eKz0Lo1GRgk@4ax.com...
> On Mon, 20 Sep 1999 20:02:33 -0700, "Hank Oredson" <horedson@att.net>
wrote:
> >Gary Coffman <ke4zv@bellsouth.net> wrote in message
> >news:DHrmNx+s2SaofDUoViT9sz9jVUYr@4ax.com...
> >> On Sun, 19 Sep 1999 22:50:35 -0700, "Hank Oredson" <horedson@att.net>
> >wrote:
> >> >Gary Coffman <ke4zv@bellsouth.net> wrote in message
> >> >news:tinlN9QLyMKyqvyn62g+MzZSipIu@4ax.com...
> >> >
> >> >> Note, an external amplifier is not a good idea. You don't
> >> >> need the extra TR delay, and any path that can't be made
> >> >> with the 5-10 watts available from the transverter probably
> >> >> has too much multipath to be useful anyway (though with
> >> >> the FEC now built into the modems, multipath is less of a
> >> >> concern).
> >> >
> >> >Gary,
> >
> >Hmmm ... "external" amplifier. Didn't think I said that ...
>
> You said,
>
> "Some assembly required i.e. the transverter and amplifier
> you will need to make a useful system".
>
> The only way to read that is if you're talking about an amplifier
> external to the transverter. Otherwise, no assembly would be
> required between the transverter and the amplifier.
>
> >Why any extra delay? Whether the final transistor is 10W
> >or 100W, the delay should be (about) the same: a few ms. max.
> >Certainly true for my HF radios. No reason to think vhf/uhf/shf
> >would be any different.
>
> It is *possible* to design an amp like that, but off the shelf
> amateur UHF external amps generally don't have fast TR.
> 100 to 200 milliseconds is typical, and far too slow for use
> on a fast network unless you're doing permanently nailed
> up duplex point to point links. The thing is, permanent network
> links need to be properly engineered anyway, so the whole
> issue of alligators becomes moot at that point.
I thought, from what I wrote, it would be obvious I consider
what goes between the PACCOM unit and the antenna to be
a single object. I understand that object might be constructed
of more than one "module". That object, whatever you want
to call it, needs to produce more than 10W into the feedline
for it to be useful in the application I have in mind. However
that higher power is obtained does not matter. Of course it
must have a reasonable switching time, and I thought that was
well covered in the third paragraph. Only one such module comes
to mind off hand, and I do not know if they are still for sale.
I'm not much interested in "typical", but rather in "where can
I get what I need for this project."
Why do you keep saying "alligator"? That means a station
which hears poorly compared to how well it can be heard
by normal stations. I am certainly not talking anything like
that, but rather matched stations that obtain their required
power spread via the use of reasonable power and good
antennas. Remember: this is a point to point link I'm working
on. It could well be full duplex, thus avoiding T/R switch time
issues. However I wish to consider the half duplex alternative
because it is easier to coordinate a single frequency.
I guess my bottom line is that I'm not at all interested in why
this cannot be done. I'm only interested in how to go about
doing it. Where there are no links, a not-quite-perfect link
is a huge improvement.
Have begun gathering the needed test gear, which I need in any
case to be able to get some existing 9600 baud links working
properly. But I still need someone for the "other end" of the
high speed link
--
... Hank
http://horedson.home.att.net
>.
------------------------------
Date: Wed, 22 Sep 1999 18:21:33 -0700
From: "Hank Oredson" <horedson@att.net>
Subject: Let's look at real numbers for TNC software sales
Gary Coffman <ke4zv@bellsouth.net> wrote in message
news:NQTpNzrqje43+pQ9xX0FRrQAmrZO@4ax.com...
> On Mon, 20 Sep 1999 20:02:33 -0700, "Hank Oredson" <horedson@att.net>
wrote:
> >KE4ZV wrote:
> >> Paths that don't qualify simply aren't used. That's just good
> >> network engineering practice. That often means that the most
> >> direct path isn't usable, and we have to organize the network
> >> topology to use an alternative routing. Sometimes it means
> >> rural hams are left out of the network unless they want to fund
> >> multiple hops just to serve one station. That's the way it goes.
> >
> >Works where there are people or available sites. We have a real
> >lot of empty space, without people or roads. Often it is not feasible
> >to put relays in place. Cost of obtaining a site, creating road access
> >to it, etc. is way out of line. So we have long haul links Sometimes
> >those have to cross mountain ranges. Knife edge works. Not at
> >high data rates though, due to the problems you mention.
>
> Yep, exactly so. If you're satisfied with low rate and non-realtime
usages,
> then you can do moderately long haul dedicated links. You can't sustain
> an extensive packet network that way, however, because latency becomes
> so great that very few people will tolerate it, even for non-realtime
uses. In
> other words, if a Pony Express rider could beat your packets across the
> country, your network wouldn't be sustainable.
Nonesense. I *know* quite well that you think it is impossible to have
any fun with digital radio unless everything is perfect and as speedy
as the internet and works perfectly all the time for everybody and for
all applications. Not my interest. I enjoy playing with radios and antennas
and stuff like that to see what I *can* do.
> That's what happened to the BBS "network" (which wasn't really ever a
> network in the sense of a packet switched network anyway). When it was
> the only game in town, it got a bit of use. But as soon as something
faster
> became widely available, it fell into disrepair. In other words, most of
your
> users abandoned you for the internet. You and Charles can rail about that,
> but it is fact, and ultimately one has to face facts or become permanently
> disassociated from reality.
Nonesense. History and facts disagree with your assertion.
--
... Hank
http://horedson.home.att.net
>.
------------------------------
Date: Wed, 22 Sep 1999 18:23:51 -0700
From: "Hank Oredson" <horedson@att.net>
Subject: Let's look at real numbers for TNC software sales
Gary Coffman <ke4zv@bellsouth.net> wrote in message
news:jAXpN=wxqdQGNDemAlhf9SurLuir@4ax.com...
> On Mon, 20 Sep 1999 20:02:33 -0700, "Hank Oredson" <horedson@att.net>
wrote:
> >Gary Coffman <ke4zv@bellsouth.net> wrote in message
> >Our experience is quite different. Without the high ERP,
> >we had NO LINK AT ALL.
>
> Better no link at all than a degraded network. If you're
> going to talk about large scale networks, you've got to
> look beyond the end of your own nose and consider the
> impact your poor link may be having on other parts of
> the network.
On this topic I think you are just plain wrong Gary.
Without these "marginal links" there IS NO NETWORK.
There cannot be any "impact" on network which does not exist.
What I'm trying to do is create SOME network.
--
... Hank
http://horedson.home.att.net
>.
------------------------------
Date: Wed, 22 Sep 1999 22:16:43 -0700
From: "Cathryn Mataga" <cathryn@junglevision.com>
Subject: Let's look at real numbers for TNC software sales
Hank Oredson wrote in message <7sc58o$4v$1@bgtnsc03.worldnet.att.net>...
>> That is simply do measurements of bit errors, and if they're low enough
To be continued in digest: hd_99_239I
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