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ZL3AI > APRDIG 16.07.03 16:58l 268 Lines 9557 Bytes #999 (0) @ WW
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Subj: TAPR Digest, Jul 13, 2/4
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From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
Subject: PSK-31 Transponder notes.
From: Bob Bruninga <bruninga@usna.edu>
Date: Sun, 13 Jul 2003 11:58:19 -0400 (EDT)
X-Message-Number: 9
Operation on a PSK-31 3 KHz satellite transponder is going to be totally
new and nothing like you have ever seen before. Let me explain this since
there has been some criticism of dedicating the transponder to only PSK:
1) SOftware exists that can display a horizontal waterfall and 20
simultaneous QSO's.
2) The satellite is full duplex, so you (and everyone else) can be
Transmitting 100% during the full 15 minute pass.
3) Thus instead of 1-to-1 half duplex TX/RX you end up with a GROUP event
with everyone talking to everyone simultaneously.
Not as in a bedlam of gyberish, but in the sense that as fast as you can
type, you can be commenting to anyone or everyone in the group at any
time. That is the ultimate in a low cost multi-user satellite.
You cannot do this on voice on a wideband transponder. THe human brain
cannot pay attention to 20 conversations. But with our lap-tops, and
multi-user PSK-31, we can. Thus, this satellite design is meant to take
advantage of that opportyunity and to maximize the fun for everyone. And
since it was going to be a 2m FM downilnk, anyone with an HT can receive
it.
I just thought I would add this note, because it may not be apparent how
radical this transponder can be.
de WB4APR, Bob
And since it is FM on the downlink, all the Doppler correction is done by
the software on the uplink (since each trasnmitting station can see his
OWN signal and closed-loop, keep it where it is suppposed to be in the
non-doppler downlink. If I say "ill be on 1250 Hz" then that is where I
will be throughout the pass.
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Subject: PHGr Calculator On-line
From: "Ev Tupis (W2EV)" <w2ev@arrl.net>
Date: Sun, 13 Jul 2003 11:57:35 -0400
X-Message-Number: 10
Thanks to Andy Pritchard (M0CYP) the mystery of how to properly format your
PHGr field has been removed. Take a gander yourself at:
http://www.apritch.myby.co.uk/phgrcalc.htm
Ev, W2EV
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Subject: Wanted to buy due to lightning strike
From: Dave Kaplan <dkaplan@steffeninc.com>
Date: Sun, 13 Jul 2003 11:35:23 -0500
X-Message-Number: 11
I am in need of a Paccomm Tiny2MarkII TNC with the DCD mod to replace my
unit destroyed by lightning in Tekamah, NE last week.
I also lost the power supply and radio but I have spares of those.
It's just not fair. I had not been to that site for over two years. Last
week I upgraded the node to from UIDIGIG 1.7 to 1.8B1.
Six hours after that it was dead. Is the moral of the story not to touch
what is working??????
Dave
WB0WNX
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Subject: Re: Wanted to buy due to lightning strike
From: Glenn Little WB4UIV <glennmaillist@bellsouth.net>
Date: Sun, 13 Jul 2003 13:03:16 -0400
X-Message-Number: 12
Lightning strike damage can be minimized and almost eliminated if the
installation conforms to http://www.tscm.com/MIL-HDBK-419A.PDF . This is
the military manual used to provide info top protect their communications
and ammo sites. It is a case of you can pay now and protect the site or pay
later and repair/replace the damage. The protection adds to the front end
cost, but adds to the reliability of the site. The cost of unscheduled
trips to the site far out weigh the cost of the protection.
73
Glenn
WB4UIV
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Subject: Re: WINAPRS Registration Turn Around Time?
From: "Ken Patterson" <kenp@etex.net>
Date: Sun, 13 Jul 2003 17:11:35 -0000
X-Message-Number: 13
Eric, have you heard anything from the Sproul brothers after posting your
message here on the sig?
de Ken,
N5EQT
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Subject: Re: PHGR
From: "Dave Thege" <dthege@conpoint.com>
Date: Sun, 13 Jul 2003 12:35:17 -0500
X-Message-Number: 14
That works. I misunderstood the way Bob had it written. I reread it and see
where I went wrong.. Thanks.
Dave N0XBN
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Subject: Re: WINAPRS Registration Turn Around Time?
From: Richard Garcia <k4gps@bellsouth.net>
Date: 13 Jul 2003 13:35:21 -0400
X-Message-Number: 15
Also remember it is summer break, they may be away on vacation since
they work at a University.
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Subject: Re: PHGR
From: James Jefferson Jarvis <jj@aprsworld.net>
Date: Sun, 13 Jul 2003 12:49:40 -0500
X-Message-Number: 16
>should for now) and still displays the 4 digits properly. No one is
>decoding PHGR, we just want to see if it is backwards compatible with
Bob and list,
aprsworld.net is decoding the PHGR (rate) packets. I've implemented Ev's
suggestion from Friday and expect to have it online on a production server
on Monday.
-Jim
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Subject: Re: [ Bob Bruninga ] New Linear Transponder HELP needed (+2)
From: "Gregg G. Wonderly" <gregg@skymaster.cytetech.com>
Date: Sun, 13 Jul 2003 12:57:46 -0500
X-Message-Number: 17
>On Sun, 13 Jul 2003, Andrew VK4TEC wrote:
>
>>Do you think that PSK will play a big role with APRS in the future ?
>
>No. PSK-31 is a human QSO mode.
Bob, you know that there is a difference between PSK and the popular
application of that mode called PSK-31, which currently, mostly includes
hand typed and received transmissions.
It is very possible to use PSK for other purposes to expand the effective
power of a transmission in this mode. I, for instance, in very interested
in creating a new PSK application on VHF and UHF that would allow us to use
SSB for APRS like applications and get a lot more useable bandwidth out of
the 15khz bandwidth that we are currently using in FM. I could imagine a
full duplex SSB path between two stations with VHF out and UHF in...
-----
gregg@cytetech.com (Cyte Technologies Inc)
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Subject: Re: PHGR
From: "Tim Taylor" <Jakie@vcn.com>
Date: Sun, 13 Jul 2003 13:27:21
X-Message-Number: 18
Look into UI-Traffic for UI-View. It should solve any problems with PHGR
and UI-View. Find it at www . apritch.myby.co.uk/uiview.htm under
add-ons.
Tim/KJ7AZ
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Subject: PHGR
From: "Tim Taylor" <Jakie@vcn.com>
Date: Sun, 13 Jul 2003 13:45:44
X-Message-Number: 19
I sat up three of the local digi's to the PHGR format to see how it works.
KJ7AZ-5, KJ7AZ-6, KJ7AZ-8. The I-Gate, KJ7AZ has been set up with it for a
long time using UI-View with UI-Traffic.
I'll change the other digi's later.
Tim/KJ7AZ
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Subject: packet repeater?
From: Wes Johnston <wes@johnston.net>
Date: 13 Jul 2003 15:13:32 -0400
X-Message-Number: 20
I was just thinking... what if we had a bit regenerating packet repeater
with an input 3mhz away from 147.39 at 147.40 <=> 147.59? What sort of
duplexer would be needed? Could I get away with 2 cavities instead of
6? Yes, I know all the nay sayers and arm chair lawyers will pop up on
this one.
What I'm thinking is to have a normal digipeater on 144.39. Then, tied
to the SAME transmitter, a bit regenerating packet repeater with an
input somewhere else. In this way, locals (who know the input
frequency) can have priority over simplex operations or DX packets the
wide may be hearing. In other words, we'll have a digpeater with TWO
inputs - one of the inputs will be REPEATED live onto 144.39, the other
will be DIGIPEATED on 144.39. If we space the frequencies out far
enough, then we don't have to use an expensive duplexer.
Wes
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Subject: Re: packet repeater?
From: Robbie <mwrobertson@comcast.net>
Date: Sun, 13 Jul 2003 14:31:42 -0500
X-Message-Number: 21
First of all Wes, please re read you post, 3 mhz away, and then repeat
on 144.39 and then digipeat on 144.39.. :-) you've lost me, please say
again your last...
robbie, wa9inf
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Subject: Re: packet repeater?
From: Tim Schall <ka7pbi@fortgirlfriend.ampr.org>
Date: Sun, 13 Jul 2003 12:51:53 -0700
X-Message-Number: 22
I understand what Wes is saying. Technically it's more than feasable. You
might even be able to get enough isolation by simple antenna seperation.
No duplexors needed.
Of course you'd probablly be better off using something other than one of
those brain damaged Kantronics TNC's. Something computer based, like
digi_ned, could be employed and set to retransmit everything it heard
'first' out the 144.39 port as well as digipeating everything on the
alternate frequency and leaving it there. If that makes sense. We do that
here in Seattle. The tcip-ip stations on 144.95Mhz beacon their own
positions on that frequency as well as cross-frequency digi them out on
144.39. They also form their own little aprs network on 144.95. We also
have a network on 440.875Mhz that behaves in a similar manner.
Is it a good idea? Personally I think it's a great idea. If the "arm chair
lawyers" don't like it they can kiss my finals....
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