| |
ZL3AI > APRDIG 13.03.04 14:05l 257 Lines 9366 Bytes #999 (0) @ WW
BID : 3004-ZL3AI
Read: GUEST
Subj: TAPR Digest, Mar 11, 1/2
Path: DB0FHN<DB0FOR<DB0MRW<OK0PKL<OK0PPL<DB0RES<ON0AR<ZL2BAU<ZL2BAU<ZL3VML
Sent: 040313/1133Z @:ZL3VML.#80.NZL.OC #:20826 [Chch-NZ] FBB7.00i $:3004-ZL3AI
From: ZL3AI@ZL3VML.#80.NZL.OC
To : APRDIG@WW
TAPR APRS Special Interest Group Digest for Thursday, March 11, 2004.
1. Re: On The Glass Antennas
2. RE: Compressed Packet Calculator
3. Re: Weather Data on the Internet
4. Re: PocketAPRS Website
5. NOTICE: fourth is down
6. NOTICE: fourth.aprs.net is back up
7. RE: I need a Guinea Pig that uses WinAPRS
8. mp3 player without any wire comes out with a very good price!
9. Re: Pre-emphasis / De-emphasis & D700 Question?
10. SPOOFED EMAIL ADDRESS
11. UI-View Compressed WX Packet & findU
12. Re: Pre-emphasis / De-emphasis & D700 Question?
----------------------------------------------------------------------
Subject: Re: On The Glass Antennas
From: "Germino" <mgermino@sbcglobal.net>
Date: Wed, 10 Mar 2004 20:59:41 -0800
X-Message-Number: 1
Radio Shack #19-324
On the back of the package it shows for 2meters the "TYPICAL 2 METER SWR
CURVE" it shows 2:1 from just below 144 to just above 148. For the70cm
graph it shows 2:1 from 436 up and beyond 465 MHz.
146 MHz and 445 MHz were the low SWR points on the Graphs.
I have the package here if you have any other questions.
Mike
73, AD6AA
Subject: [aprssig] On The Glass Antennas
>Does any one know the bandwidth of dual band On The Glass antennas? Would
>like 2meters plus (may be up to 155) and also 448 to 468mhz. These seem to
>be difficult to find. Does the RS antenna cover this range???
>Ron
>WA2WWK
----------------------------------------------------------------------
Subject: RE: Compressed Packet Calculator
From: "Scott Miller" <scott@3xf.com>
Date: Wed, 10 Mar 2004 21:35:52 -0800
X-Message-Number: 2
I wrote a Base-91 implementation for the OpenTracker a few weeks ago. If I
get a chance tomorrow I'll see if I can whip up a Javascript version or
something.
Scott
N1VG
-----Original Message-----
Has anyone designed a Compressed Packet Calculator???
----------------------------------------------------------------------
Subject: Re: Weather Data on the Internet
From: "Russ Chadwick" <russ@wxqa.com>
Date: Thu, 11 Mar 2004 05:46:30 -0000
X-Message-Number: 3
There has been some discussion here of how often one should send weather
data to APRSWXNET/Citizen Weather Observer Program (CWOP).
Whenever a new member of APRSWXNET/CWOP asks how often they should send
data, I say they should use whatever data rate they wish as long as it's
not faster than one packet every 5 minutes. I make this same suggestion for
both the internet and for RF. If you'd like to see the number of packets
that the different stations send in, I post that information under item one
on this page,
http://www.wxqa.com/onewt238.html
These are most of the weather stations on the APRS-IS. Right now we have
about 1400 member stations sending in data regularly and these data are send
to users. There are about 3000 names in the CWOP member database and this
number increases every day.
The NOAA/Forecast systems Lab (FSL) Central Facility downloads data from
findu.com every 15 minutes. Most of the members sending in data via the
internet send at the 5 minute rate. The reason for this discrepency is
entirely due to equipment limitations in the FSL Central Facility. Most of
the users would like to receive the data at the higher rate. I am pushing
to have the 5 minute data rate adopted by the FSL Central Facility as there
have been equipment changes recently.
The capsizing incident that happened in Baltimore Harbor on Mar 6 at about
2100 UTC shows the need for the faster data rate. Unfortunately, five
people were drowned when a sudden gust of wind over turned a water taxi.
Several CWOP stations measured gustiness and CW1550, located about 4 miles
to the west of Baltimore Harbor measured the remarkable isolated gust shown
in this URL if you view it before March 16,
http://www.findu.com/cgi-bin/wxpage.cgi?call=CW1550&units=english&last=240
Clearly, timliness of data is an important issue for fast-moving hazardous
weather systems like this one.
Russ KB0TVJ
----------------------------------------------------------------------
Subject: Re: PocketAPRS Website
From: James Smith <k9apr@sbcglobal.net>
Date: Thu, 11 Mar 2004 04:11:21 -0500
X-Message-Number: 4
Work fined here http://www.pocketaprs.com
Jason Rausch wrote:
>Can anyone else get pocketaprs.com to come up? Has Mike completely jumped
>ship? The last update on the page did'nt sound too good for the future of
>the program.
----------------------------------------------------------------------
Subject: NOTICE: fourth is down
From: "Kurt A. Freiberger" <kurt@badgers-hill.net>
Date: Thu, 11 Mar 2004 09:10:22 -0600
X-Message-Number: 5
fourth.aprs.net is down for the nonce, due to the campus losing
connectivity. It appears that the campus firewall threw a clot this
morning around 3:30, and they're working on getting it resurrected. More
news as it happens.
73/Kurt
for n5jxs@tamu.edu
--
Kurt A. Freiberger Austin, TX kurt@badgers-hill.net
Amateur Radio Callsign WB5BBW AIM Handle: WB5BBW
"Some people are like Slinkys - Generally considered useless, but
you can't help smiling when you see them falling down the stairs."
----------------------------------------------------------------------
Subject: NOTICE: fourth.aprs.net is back up
From: "Kurt A. Freiberger" <kurt@badgers-hill.net>
Date: Thu, 11 Mar 2004 09:59:51 -0600
X-Message-Number: 6
We have connectivity once again.
73/Kurt
--
Kurt A. Freiberger Austin, TX kurt@badgers-hill.net
Amateur Radio Callsign WB5BBW AIM Handle: WB5BBW
"Some people are like Slinkys - Generally considered useless, but
you can't help smiling when you see them falling down the stairs."
----------------------------------------------------------------------
Subject: RE: I need a Guinea Pig that uses WinAPRS
From: "Christensen, Eric" <CHRISTENSENE@MAIL.ECU.EDU>
Date: Thu, 11 Mar 2004 12:24:49 -0500
X-Message-Number: 7
Testing has been completed... Thanks for all offers.
Eric
-----Original Message-----
From: Steve Wilson [mailto:kf6wax@cox.net]
don't wait for a flood of replies Eric! <G>
Steve
----- Original Message -----
From: "Christensen, Eric" <CHRISTENSENE@MAIL.ECU.EDU>
>I am looking for someone that is at least on the IS that is using
>WinAPRS to
>contact me for a test.
>
>Thanks,
>Eric
----------------------------------------------------------------------
[spam]
----------------------------------------------------------------------
Subject: Re: Pre-emphasis / De-emphasis & D700 Question?
From: Jeff King <jeff@aerodata.net>
Date: Thu, 11 Mar 2004 13:53:47 -0500
X-Message-Number: 9
On Wed, 10 Mar 2004 15:05:34 -0500, Robert Bruninga wrote:
>My understanding is that the D7 did not do pre/de emphasis and works
>directly (flat) with the modulator and demodulator. This is not like
>most appliance operators who just plug a TNC into the speaker and
>mic jacks (that does do pre/deemphsis.).
Yes. But also understand, that pre/de-eemphsis is a standard for FM voice
radios, and when you use AFSK modems (1200 baud), that is the standard, since
it is a audio baseband modem.> 6db per octave<. You can't go mixing and
matching this, irregardless of what some manufacturer decides to do. A
standard is a standard is a standard.
>Kenwood compensated a little on the D700 which came out later and
>made it have some pre emphasis (I think) but not the full 6 dB per
>octve of normal FM voice.
.....
>So it is good that you asked. If you want to favor the mobiles then
>dont use pre/de emphasis.
That is assuming every mobile uses the Kenwood APRS units? They don't, and I
have a problem with catering to every manufacturing that wants to break
specifications. Wouldn't it be better, to those using the Kenwood units, to
just provide the proper amount of de/pre emphsis? I'd think a simple R/C
inserted in the TX audio path could get it closer. Maybe you can suggest to
Kenwood they can either do a recall or publish a fix if it is as far off as
you say it is. Here is a fix someone else came up with on their own for
another Kenwood radio:
http://www.febo.com/packet/layer-one/kenwood-tmv7a.html
>If you want to favor fixed stations that
>use speaker and mIC connections, then your digi should favor the
>de/preemphasized crowd...
I.E. the "crowd" that is following the spec.
Or let me put it another way. Lets say at Dayton this year, Icom comes out
with a APRS rig. For whatever reason, it has a pre/de emphisis of 8 db/per
octave. Because of their much lower price, they sell twice as many as the
Kenwood rigs. So, does that now mean the new standard is 8db/per octave as
compared to Kenwoods 0db/per octave? No, it doesn't. The standard for FM is
6db/per octave. Period.
BTW, regarding you comment about decoding signals with 1 or 2 "ticks", I can
do that with a standard set of mobile rigs. The way I do this is by not over
driving the transmitter. This is where the Kenwoods have the advantage
because the units are matched and there is no user intervention. Nice, but I
really don't think it is that much effort to properly set up a transmitter so
that everyone on the channel can benefit from this. Here is a good paper on
the subject:
http://www.febo.com/packet/layer-one/transmit.html
http://www.febo.com/packet/layer-one/index.html
----------------------------------------------------------------------
Read previous mail | Read next mail
| |
