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CX2SA > SATDIG 16.11.08 14:06l 952 Lines 30398 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. operating protocol (Jim Danehy)
2. AO07 - where is everybody? (Mark Lunday, WD4ELG)
3. Slow scan fun (John Price)
4. ao-50 first contact (Eric Fort)
5. ANS-321 AMSAT Weekly Bulletins (Lee McLamb)
6. Re: ao-50 first contact (John Marranca, Jr)
7. AO-51 Images (WCP)
8. Re: ao-50 first contact (Patrick STODDARD (WD9EWK/VA7EWK))
9. Some doppler observations/questions (Mark Lunday, WD4ELG)
10. AO 7 comments (Jim Danehy)
11. Re: Some doppler observations/questions (Luc Leblanc)
12. Re: Some doppler observations/questions (Alan Cresswell)
13. Re: Some doppler observations/questions (Simon (HB9DRV))
----------------------------------------------------------------------
Message: 1
Date: Sat, 15 Nov 2008 16:23:43 -0500
From: "Jim Danehy" <jdanehy@xxxxx.xx.xxx>
Subject: [amsat-bb] operating protocol
To: <amsat-bb@xxxxx.xxx>
Message-ID: <9CEC64C7095C42659EFBC33EB93D4479@xxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
I hear folks just call : " CQ Oscar" during a pass without establishing
a
contact. Most FM satellites usually generate a lot of traffic during a
pass. I
would suggest that if you are new to operating the satellites, that you
wait
until you hear other stations before transmitting. If you are not hearing
anyone during what could be called a peak time pass ( evenings during the
week
and any time on weekends) then you should refrain from calling CQs which
last
for ten minutes. You may think there is nobody on frequency. But there are
often many stations using the satellite at the time you are CQing. An
unanswered CQ just increases the volume of QRM.
If you are operating duplex (hearing the satellite while you transmit) and
you
can hear your own signal then by all means call someone. Not operating
duplex
and calling CQ can mean that you are not listening to the downlink on its
proper frequency (corrected for the doppler effect).
I have attempted several times to email the operators of such stations and
interact with them to correct their problem of not hearing. I am amazed at
the
answers I get from these operators. Often it becomes obvious why they are
not
hearing and why they are "alligators" ( all mouth no ears).
I well realize that not everyone is set up to operate duplex. That just
means
you should first hear other stations before you call CQ for minutes on
end.
These FM satellites have a lot of traffic and are rarely without stations
carrying on QSOs.
Let me suggest that we all attempt to "Elmer" these new operators so that
they
can enjoy the satellites as we do. Many have emails listed on QRZ. COM.
For
others, they may find that the operator is a local in the same town or
County.
Thanks for reading and I hope we can help newcomers.
73
Jim W9VNE
EM79tb
------------------------------
Message: 2
Date: Sat, 15 Nov 2008 19:33:01 -0500
From: "Mark Lunday, WD4ELG" <mlunday@xx.xx.xxx>
Subject: [amsat-bb] AO07 - where is everybody?
To: <amsat-bb@xxxxx.xxx>
Message-ID: <000001c94782$e24ac000$a6e04000$@xx.xxx>
Content-Type: text/plain; charset="us-ascii"
Saturday evening East Coast time, the bird is going right overhead. All I
hear is W9VNE on CW (always reliable signal!), and two SSB signals.
I call CQ for the entire 20 min of the pass with my 5 watts. I have two
rigs so I CAN hear myself. Where is everybody? Would love to set up a CW
sked for Sunday for the 2209 UTC pass (Eastern US/Atlantic) or the 0002
UTC
pass (central US).
Mark Lunday
WD4ELG
wd4elg@xxxx.xxx
http://wd4elg.net
------------------------------
Message: 3
Date: Sat, 15 Nov 2008 20:53:36 -0500
From: "John Price" <n4qwf1@xxxxx.xxx>
Subject: [amsat-bb] Slow scan fun
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Message-ID:
<8d1b8e80811151753m4fe6dc59p72f980996fd7108d@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Thanks to all who posted images via AO-51 this evening. What a neat
mode to have the opportunity to experiment with. Since the resent ISS
SSTV effort there new interest I am sure. Sure hope the availability
of this mode is continued in the future. Thanks to the command team
for making it possible.
73's << John
--
N4QWF Amateur Radio Operator
AO-7,AO-27,SO-50,AO-51,VO-52,ISS
Internet N4QWF@xxxxx.xxx
Echolink nodes #110903 -L #388463
Formerly KC4AHW VK3FEZ
Amsat Member #27845
DXCC #33,478
VUCC SAT #135
WAS SAT #296
51 on AO-51 #13
LON -79.256 LAT 37.459 Grid FM07il
>From the Foothills of the Blueridge
*Life should not be a journey to the grave with the intention of
arriving safely in a pretty and well preserved body, but rather to
skid in broadside, thoroughly used up, totally worn out, and loudly
proclaiming - "WOW, What a ride!"
------------------------------
Message: 4
Date: Sat, 15 Nov 2008 18:05:21 -0800
From: "Eric Fort" <eric.fort@xxxxx.xxx>
Subject: [amsat-bb] ao-50 first contact
To: AMSAT-BB <amsat-bb@xxxxx.xxx>
Message-ID:
<2ad2af430811151805h1c885c4aqff58fa1d5e5ceb11@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Finally worked my first sat contact ever tonight on S0-50 toward the end
of
the 17:13-17:26 local pass from DM14gk to DM43. thanks to WD9EWK in DM43
for the contact.
73 DE AF6EP, ERIC
AF6EP DM14GK
PS:
WD9EWK, PLEASE CONTACT FOR QSL INFO.
------------------------------
Message: 5
Date: Sat, 15 Nov 2008 20:52:01 -0500
From: Lee McLamb <ku4os@xxx.xx.xxx>
Subject: [amsat-bb] ANS-321 AMSAT Weekly Bulletins
To: amsat-bb@xxxxx.xxx
Message-ID:
<20081116025202.GRC27329.cdptpa-omta03.mail.rr.com@xxx.xxx.xx.xxx>
Content-Type: text/plain; charset="iso-8859-1"; format=flowed
AMSAT NEWS SERVICE
ANS-321
ANS is a free, weekly, news and information service of AMSAT North
America,
The
Radio Amateur Satellite Corporation. ANS reports on the activities of a
worldwide group of Amateur Radio operators who share an active interest in
designing, building, launching and communicating through analog and
digital
Amateur Radio satellites.
Please send any amateur satellite news or reports to:
ans-editor@xxxxx.xxx
In this edition:
* IARU Region 1 Conference Satellite Topics
* AMSAT Awards
* ESA's Vega Launching To An Unusual Orbit
* VHF/UHF/microwave pioneer Reg Galle, VK5QR, SK
* ARISS Status - 10 November 2008
SB SAT @ AMSAT $ANS-321.01
IARU Region 1 Conference Satellite Topics
AMSAT News Service Bulletin 321.01
From AMSAT HQ SILVER SPRING, MD.
November 16, 2008
To All RADIO AMATEURS
BID: $ANS-321.01
The IARU Region 1 Conference in Cavtat starts this weekend, see
http://www.southgatearc.org/news/november2008/iaru_r1_cavtat.htm
There are a number of Satellite related papers being discussed
in C5 VHF/UHF/uW:
144 MHz increased satellite service
3400 MHz amateur satellite allocation
Microwave spectrum requirements
A new vision for 23 cm
Amateur satellites handbook chapter
Microwave spectrum requirements
VHF spectrum requirements
An REF response to the C5 VHF/UHF/uW papers can be seen at
http://thf.ref-union.org/c5_iaru_r1/08cavtat/08cavtat_c5_etat_commentaires.
pdf
[ANS Trevor, M5AKA, for the above information]
/EX
SB SAT @ AMSAT $ANS-321.02
AMSAT Awards
AMSAT News Service Bulletin 321.02
From AMSAT HQ SILVER SPRING, MD.
November 16, 2008
To All RADIO AMATEURS
BID: $ANS-321.02
We would like to welcome the following to the satellite community. They
have made their first satellite contact and are now members of the AMSAT
Satellite Communicators Club.
Boris Lanca, 9A2GA
Douglas Anoman, KC9MLN
Steve Rish, K8SAR
The following has earned the AMSAT Satellite Communications Achievement
Award.
Jose Manuel Escribano Hinojosa #475
Jose also earned the AMSAT South Africa Satellite Communications
Achievement Award #US127.
To see all the awards visit http://www.amsat.org or
http://www.amsatnet.com
Bruce Paige, KK5DO
AMSAT Director Contests and Awards
[ANS thanks Bruce, KK5DO, for the above information]
/EX
SB SAT @ AMSAT $ANS-321.03
ESA's Vega Launching To An Unusual Orbit
AMSAT News Service Bulletin 321.03
From AMSAT HQ SILVER SPRING, MD.
November 16, 2008
To All RADIO AMATEURS
BID: $ANS-321.03
Following the selection of 9 cubesats to be launched on the maiden flight
of
the Vega launcher, ESA have now announced that the cubesats will be
deployed
into a very interesting orbit measuring 350km x 1450km with an inclination
of
71 degrees.
>From the ESA website
"The nine CubeSats will be deployed from three different deployment
systems
mounted on the support structure of the main payload, LARES (LAser
RElativity
Satellite), into an orbit of 350 km by 1450 km at an inclination of 71
degrees. The launch opportunity is offered by ESA to the selected
CubeSats
free of charge"
Further details are at:
http://www.esa.int/esaED/SEMAYTRTKMF_index_0.html
[ANS thanks David, G0MRF, for the above information]
/EX
SB SAT @ AMSAT $ANS-321.04
VHF/UHF/microwave pioneer Reg Galle, VK5QR, SK
AMSAT News Service Bulletin 321.04
From AMSAT HQ SILVER SPRING, MD.
November 16, 2008
To All RADIO AMATEURS
BID: $ANS-321.04
All those interested in long distance VHF/UHF/microwave propagation will
regret the death of Reg Galle VK5QR on 12 September 2008.
Reg was a leading pioneer of the use of these amateur radio bands.
On 31 December 1951, Reg made a 144 MHz Australian record distance of 2122
Km
with a contact with the late Rolo Everingham VK6BO in Perth (just short of
the
then world record of 2253 Km). He then continued to seek
answers to questions regarding the propagation of the higher bands.
Reg became the Adelaide end of record breaking distances on 432, 1296,
2304 and 3456 MHz across the Great Australian Bight with Wally Green
VK6WG in Albany.
Reg and Wally, as true amateurs with no professional engineering
backgrounds, built equipment for these UHF/microwave bands and were
nearly 2 000 Km apart so that there were no "local" tests with each
other. There were no precedents in Australia, and few in the world, for
trying to make contacts over this distance.
In 1977, they bridged the 1296 MHz path on 25 January for a world record
distance of 1885 Km.
The following year, on 17 February 1978, Reg and Wally made their first
contact on the 2304 MHz band. Reg used SSB that was processed in a
divide by 6 circuit and mixed to 28 MHz. The 28 MHz signal, with
processed SSB, was then transverted to 384 MHz and then tripled and
doubled to 2304 MHz. This multiplication by 6 restored the original
SSB! To give you a feel of the type of gear in use 30 years ago, Wally
Green VK6WG used a modified World War II SCR522 which, from a 7 MHz
crystal, produced 128 MHz. This was then multiplied to 384 MHz with a
BAY96 varactor tripler to 1152 MHz in a modified Microwave Modules
MMV1296 and then doubled in by a 2C39 which drew 90mA at 600V.
In 1986, Reg and Wally completed their first 3456 MHz contact using CW.
This distance of 1885 Km and that on 2304 MHz remain the Australian
record distances.
Both Wally and Reg built equipment for the 5.7 GHz band and made tests
on that band without success although Reg claimed that they could have
had a contact had Wally not been in the midst of making apricot jam on
that day!
Reg gradually lost interest in pushing the boundaries further and has
been in poor health in recent years. His death followed several
strokes. The most recent one returned him to hospital just over a week
ago but he insisted that he wanted to go home despite living alone and
with no close relatives in Adelaide. His niece watched over him and he
was able to fulfil his wish of dying at home in his own bed! Reg was 96
years old!
Farewell to a tremendous pioneer on the higher bands!
[ANS thanks Wally, VK6KZ, for the above information]
/EX
SB SAT @ AMSAT $ANS-321.05
ARISS Status - 10 November 2008
AMSAT News Service Bulletin 321.05
From AMSAT HQ SILVER SPRING, MD.
November 16, 2008
To All RADIO AMATEURS
BID: $ANS-321.05
1. Spanish Students Speak to ISS via Radio
Students attending IES Trassierra in C?rdoba, Spain spoke with astronaut
Mike
Fincke, KE5AIT, via an Amateur Radio on the International Space Station
(ARISS)
contact on Monday, November 3. Twenty students asked one question each of
the
astronaut. Approximately 150 students, teachers and guests attended the
event
including the Cordoba City mayor and the Head
Master of Education and Culture of
Cordoba. Media coverage included 4 local and regional television stations,
2
local and regional radio stations and 3 newspapers. Photos, an audio
recording
and a video recording may be found at: http://www.ariss-eu.org/2008_11_08.
htm
An article (in Spanish) has been posted to El Dia de Cordoba:
http://www.eldiadecordoba.es/article/cordoba/270358/conocer/como/vive/astro
nau
ta
.html
2. Successful Australian Contact
In preparation for an Amateur Radio on the International Space Station
(ARISS)
contact, students attending St. Thomas? Primary School in Brisbane,
Queensland,
Australia helped build an antenna. They spoke with Richard Garriott,
W5KWQ,
during his ISS mission and received Slow Scan Television (SSTV) images as
well.
They also viewed Mike Fincke?s ISS video tour taken during Expedition 9.
On
Tuesday, November 4, the students spoke with Fincke, KE5AIT, as
approximately
400 students looked on. Fincke answered all
twenty questions posed to him by the
20 students. The event received extensive local and national media
coverage
including 2 newspapers, an online magazine, 2 television stations and 5
radio
stations. The audio and a partial video of the event are available on the
school?s Web site: http://www.members.optusnet.com.au/jandnclark/?reload
An interview is available on the ABC site:
http://www.abc.net.au/local/photos/2008/11/07/2412996.htm?site=brisbane
The City South News posted an article on the contact. See:
http://city-south-news.whereilive.com.au/news/story/special-space-link-for-
local
-students/
3. India University Contact Successful
An Amateur Radio on the International Space Station (ARISS) contact
between
Dibrugarh University in Assam, India and astronaut Mike Fincke, KE5AIT,
took
place on Friday, November 7 via telebridge station W6SRJ in California.
Ten
students were able to ask eleven questions of Fincke as an audience of 700
gathered for the event. Mike spoke briefly in the Indian language. Media
coverage included newspapers and television. Contact audio was fed into
two
EchoLink servers and into the Internet Radio Linking Project (IRLP)
Discovery
Reflector 9010. There were 5 known connections from England, Japan and
South
Korea on the EchoLink servers with uncounted listeners on one repeater and
two
link nodes.
4. Successful ARISS Simulated Contacts
On Thursday, November 6, Chris Hadfield, KC5RNJ/VA3OOG, and Cady Coleman,
KC5ZTH, took part in Amateur Radio on the International Space Station
(ARISS)
simulated contacts. The astronauts spoke with two groups of students from
Manordale Public School in Ottawa, Ontario,
Canada. These training sessions were
terrestrial-based amateur radio contacts using ARISS-equivalent equipment.
Hadfield and Coleman are currently assigned as back-up Expedition 19 crew
members.
5. ARRL Articles on Garriott Mission
On Thursday, November 6, the American Radio Relay League (ARRL) ran an
article
on Richard Garriott?s mission. ?Richard Garriott, W5KWQ, Back on Terra
Firma,?
may be found at: http://www.arrl.org/news/stories/2008/11/06/10437/?nc=1
The ARRL Letter also ran the story. See:
http://www.arrl.org/arrlletter/08/1107/
6. Interview on SuitSat
ARISS (Amateur Radio on the International Space Station) member Steve
Bible,
N7HPR, gave an interview on the concept and development of SuitSat-1. His
interview has been posted to the Design News, Engineering Concept Conduit
Web
page. See: http://www.engineeringconceptconduit.com/
7. Astronaut Makes General Contacts
Mike Fincke, KE5AIT, made several contacts with
the ham radio community over the
November 8 weekend. Using the Amateur Radio on the International Space
Station
(ARISS) equipment, Fincke talked with stations in Australia, Thailand,
South
America and North America.
8. ARISS SSTV Web Site Status
The Amateur Radio on the International Space Station (ARISS) Slow Scan
Television (SSTV) Web site set up for Richard Garriott?s flight was a big
success. Over 2200 images from SpaceCam, MMSSTV and the VC-H1 were
received by
amateur radio operators worldwide and were uploaded to the site. The site
received nearly 4 million hits! See the SSTV images:
http://ariss-sstv.ssl.berkeley.edu/SSTV/ and the SSTV blog:
http://ariss-sstv.blogspot.com/
[ANS thanks Carol, KB3LKI, for the above information]
/EX
In addition to regular membership, AMSAT offers membership in the
President's
Club. Members of the President's Club, as sustaining donors to AMSAT
Project
Funds, will be eligible to receive additional benefits. Application forms
are
available from the AMSAT Office.
73,
This week's ANS Editor,
Lee McLamb, KU4OS
ku4os at amsat dot org
------------------------------
Message: 6
Date: Sat, 15 Nov 2008 21:56:53 -0500
From: "John Marranca, Jr" <KB2HSH@xxxxx.xxx>
Subject: [amsat-bb] Re: ao-50 first contact
To: amsat-bb <amsat-bb@xxxxx.xxx>
Message-ID:
<8edcdb130811151856u264898bei46714269576e418f@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Eric:
I'm sure that I speak for everyone, when I/we say WELCOME to the Satellite
community. You accomplished a great feat today. Now don't stop
there...and
don't stop learning how to advance your skill.
And, don't be afraid to ask questions. Everyone on the BB is
exceptionally
friendly, and advice is ALWAYS accurate and timely.
73 de John KB2HSH
KB2HSH.blogspot.com
--
_______________________________
John Marranca, Jr
PBX Technician/Shop Steward CWA Local 1122
BN Systems, Inc
Orchard Park, NY
(716)972-2006
------------------------------
Message: 7
Date: Sat, 15 Nov 2008 22:57:28 -0500
From: "WCP" <wcp2@xxxxx.xxx>
Subject: [amsat-bb] AO-51 Images
To: <amsat-bb@xxxxx.xxx>
Message-ID: <000f01c9479f$71e56140$1401a8c0@xxxxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
John where are they posted ?
------------------------------
Message: 8
Date: Sat, 15 Nov 2008 21:31:34 -0700
From: "Patrick STODDARD (WD9EWK/VA7EWK)" <amsat-bb@xxxxxx.xxx>
Subject: [amsat-bb] Re: ao-50 first contact
To: amsat-bb@xxxxx.xxx
Message-ID:
<2e18ad3e0811152031m2dca4c42h8e2fae26f55200d1@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Hi!
> Finally worked my first sat contact ever tonight on S0-50 toward the end of
> the 17:13-17:26 local pass from DM14gk to DM43. thanks to WD9EWK in DM43
> for the contact.
I'm glad to have been your first satellite contact. There was at least
one
other station who had been calling you, once your call was heard on the
downlink. For our contact, I was located in grid DM43iu northeast of
Phoenix.
I have sent you directly an MP3 of the audio from that pass, including our
contact. With that, you can hear how you sounded through the satellite
at my location. You had been partially getting through the satellite
earlier
in the pass before our contact, and you were loud and clear for our QSO.
What were you using for your station?
As I mentioned in the message I sent directly to you with the MP3, I will
send you a QSL card in the coming week for this contact. If you'd like to
send me one, my mailing address as listed on my web pages and at
QRZ.com is correct.
Good luck with the satellites, and 73!
Patrick WD9EWK/VA7EWK - tonight in Tonto Basin, AZ
http://www.wd9ewk.net/
------------------------------
Message: 9
Date: Sat, 15 Nov 2008 23:57:33 -0500
From: "Mark Lunday, WD4ELG" <mlunday@xx.xx.xxx>
Subject: [amsat-bb] Some doppler observations/questions
To: <amsat-bb@xxxxx.xxx>
Message-ID: <000001c947a7$d66f2ad0$834d8070$@xx.xxx>
Content-Type: text/plain; charset="us-ascii"
I am using HRD with Sat tracker module (thanks, Simon!)
I notice that for the non-FM birds I am working (AO7, FO29, VO52) the
Doppler is never quite exact. Or I guess I should say there seems to be a
constant *offset* that needs to be included in the Doppler calc. Tonight
on
AO7 mode B pass, my actual downlink frequency seemed to be about 4 kHz
lower
than what it should be according to the Doppler. As the bird passed by, I
followed the "one true rule" and only adjusted the higher freq (uplink in
this case). It was consistently about 4 kHz lower.
On FO29 pass, there seemed to be about a 2 kHz offset. When the bird
passed
overhead, the Doppler "flipped" quickly and I had to find my signal again.
How can I consistently determine this offset so I can include it in with
the
Doppler correction? Or is it on a case-by-case basis?
PS Thanks, Frank, K9CIS, for the nice CW rag chew on FO29 tonight.
Mark Lunday
WD4ELG
wd4elg@xxxx.xxx
http://wd4elg.net
------------------------------
Message: 10
Date: Sun, 16 Nov 2008 00:50:00 -0500
From: "Jim Danehy" <jdanehy@xxxxx.xx.xxx>
Subject: [amsat-bb] AO 7 comments
To: <amsat-bb@xxxxx.xxx>
Message-ID: <20BBAFC4E5FF46239446996CDCFF8012@xxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Mark (WD4ELG)
Thanks for the comment on my CW signal . . . I prefer CW so I attempt to
generate some activity on AO 7 whenever I can . . . hope to catch you on
Sunday . . .
RE : doppler . . . . my experience is that doppler is pretty dynamic
rather
than static . . . a lot of variables such as height, angle to your QTH
that
change from pass to pass . . . I use SatPC32 to control the doppler . . .
i
have made up a little chart for the non-FM birds and dial in the
adjustment
(to the uplink) before the pass . . . . I notice that on AO7 when I work
Europe (a very low elevation for me) that I need to dial in a lot more
adjustment (almost 2 khz) . . . . I use an Icom 910H and its RIT is
limited
to 1 khz which is a little bit of a pain . . . . i have the RIT on and
like
to be able to use it on stations that do not use computer control of their
rigs . . . I do not think you can "nail" the frequency consistently . . .
in
my experience on the non-FM satellites it is just something you take into
account . . .
You ask about the activity level too . . . well all of the non-FM
satellites
suffer from relative lack of use compared to the FM satellites. Doppler
is
not as much of a factor because of the FM signal's width . . . . I use
the
AFC (automatic frequency control) on my 910 too in FM mode which really
solves
the (doppler) problem . . . I think the doppler effect on non FM signals
is
really too much for many of the users . . . that signal really moves
around
albeit in the same direction . . . use of a computer to control it reduces
the
number of successful users . . . I do hear people struggling (as I did)
to
get the doppler issue under control . . . I also think that there is a lot
more FM rigs in use compared to the multi mode rigs . . . thus more
relative
activity . . in sorting through my collection of QSLs from satellite QSOs
I
find that there is a preponderance of HTs . . I do not use an HT even on
the
FM birds . .
One more thing : AO 7 is really old ( 1974 ) and suffers from old age
(very
sensitive to the use of high power) I usually use 5 watts on CW . . .
today I
worked K9CIS who was using 7/10ths of a watt . . . we rag chewed for 10
minutes . . . anyone who uses excess power causes the transponder on AO 7
to
sound choppy with the offending signal being heard up and down the band
in 3
or 4 places, often making AO 7 unusable for many. . . I stick to CW and
use
the CW filter which helps me overcome the hash that is generated by
stations
using too much power . . . . folks really need to keep their ERP
(effective
radiated power) down to 100 watts or less on AO7. That means if you are
using
25 watts output your antenna should not exceed 6 db gain (a factor of 4
times). Most satellite users on non FM birds use yagis that have 10 db +
or
more gain which means they should keep their power to 10 watts . . .
unfortunately that remains a problem . . .more is less in that situation .
.
Look forward to exchanging reports with you . . .
73 Jim W9VNE
EM79tb
------------------------------
Message: 11
Date: Sun, 16 Nov 2008 00:38:57 -0500
From: Luc Leblanc <lucleblanc6@xxxxxxxxx.xx>
Subject: [amsat-bb] Re: Some doppler observations/questions
To: amsat-bb@xxxxx.xxx
Message-ID: <491F6BA1.27929.33A0C81@xxxxxxxxxxx.xxxxxxxxx.xx>
Content-Type: text/plain; charset=US-ASCII
On 15 Nov 2008 at 23:57, Mark Lunday, WD4ELG wrote:
> I am using HRD with Sat tracker module (thanks, Simon!)
>
> I notice that for the non-FM birds I am working (AO7, FO29, VO52) the
> Doppler is never quite exact. Or I guess I should say there seems to be a
> constant *offset* that needs to be included in the Doppler calc. Tonight on
> AO7 mode B pass, my actual downlink frequency seemed to be about 4 kHz lower
> than what it should be according to the Doppler. As the bird passed by, I
> followed the "one true rule" and only adjusted the higher freq (uplink in
> this case). It was consistently about 4 kHz lower.
>
> On FO29 pass, there seemed to be about a 2 kHz offset. When the bird passed
> overhead, the Doppler "flipped" quickly and I had to find my signal again.
>
> How can I consistently determine this offset so I can include it in with the
> Doppler correction? Or is it on a case-by-case basis?
>
> PS Thanks, Frank, K9CIS, for the nice CW rag chew on FO29 tonight.
>
> Mark Lunday
> WD4ELG
> wd4elg@xxxx.xxx
> http://wd4elg.net
I am starting to implement automatic doppler control and i note the same
effect. I guess it is related to the step of adjustment. I am
using 10 hertz and i think especially at TCA on vertical elevation pass
the
10HZ step is not enough i have to manually adjust to compensate
for this lag. I will try to use higher step.
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 12
Date: Sun, 16 Nov 2008 06:46:54 -0000
From: "Alan Cresswell" <alancresswell@xxxx.xx.xx>
Subject: [amsat-bb] Re: Some doppler observations/questions
To: <amsat-bb@xxxxx.xxx>
Message-ID: <AAAEB49DE7A44FD4AE77C38384815E35@xxxxxxxxx>
Content-Type: text/plain; charset="us-ascii"
Hi Mark,
Almost all the linear sats have some offset due to variations in frequency
of the internal oscillators etc. In the case of AO-07 the offset is
temperature related and varies slowly depending on the amount of sunlight
etc. (AO-07 at the moment is about 4.5kHz) The technique I use to
determine
the offset at any time is to set my receiver to the centre of the
satellite
downlink passband (+/- Doppler) and then adjust my transmitter frequency
to
hear myself correctly on the downlink. The difference between my actual
uplink (+/- Doppler) and the nominal centre of the uplink passband is the
offset. I save this value and use it built into my Doppler correction
until
any change warrants a re-calculation.
Alan
ZL2BX
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Mark Lunday, WD4ELG
Sent: Sunday, 16 November 2008 04:58
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Some doppler observations/questions
I am using HRD with Sat tracker module (thanks, Simon!)
I notice that for the non-FM birds I am working (AO7, FO29, VO52) the
Doppler is never quite exact. Or I guess I should say there seems to be a
constant *offset* that needs to be included in the Doppler calc. Tonight
on
AO7 mode B pass, my actual downlink frequency seemed to be about 4 kHz
lower
than what it should be according to the Doppler. As the bird passed by, I
followed the "one true rule" and only adjusted the higher freq (uplink in
this case). It was consistently about 4 kHz lower.
On FO29 pass, there seemed to be about a 2 kHz offset. When the bird
passed
overhead, the Doppler "flipped" quickly and I had to find my signal again.
How can I consistently determine this offset so I can include it in with
the
Doppler correction? Or is it on a case-by-case basis?
PS Thanks, Frank, K9CIS, for the nice CW rag chew on FO29 tonight.
Mark Lunday
WD4ELG
wd4elg@xxxx.xxx
http://wd4elg.net
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------------------------------
Message: 13
Date: Sun, 16 Nov 2008 08:29:43 +0100
From: "Simon \(HB9DRV\)" <simon@xxxxxx.xx>
Subject: [amsat-bb] Re: Some doppler observations/questions
To: "Mark Lunday, WD4ELG" <mlunday@xx.xx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <CC69479AAE044239AABA2C0A75FDE69E@xxxxxxxxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
A couple of ideas:
1) Make sure your Lat / Lon is correct - very correct.
2) Make sure you use good Kepler data, for example from www.celestrak.com
.
I test with the CW beacon on LO-19 - if the pitch does not change during a
pass then the Doppler is spot-on.
I also notice offsets with some sats - as other have commented this is the
LO on the satellite although it could also be the LO on the radio.
Simon Brown, HB9DRV
www.ham-radio-deluxe.com
----- Original Message -----
From: "Mark Lunday, WD4ELG" <mlunday@xx.xx.xxx>
>
> I notice that for the non-FM birds I am working (AO7, FO29, VO52) the
> Doppler is never quite exact. Or I guess I should say there seems to be a
> constant *offset* that needs to be included in the Doppler calc. Tonight
> on
> AO7 mode B pass, my actual downlink frequency seemed to be about 4 kHz
> lower
> than what it should be according to the Doppler. As the bird passed by, I
> followed the "one true rule" and only adjusted the higher freq (uplink in
> this case). It was consistently about 4 kHz lower.
>
> On FO29 pass, there seemed to be about a 2 kHz offset. When the bird
> passed
> overhead, the Doppler "flipped" quickly and I had to find my signal again.
>
------------------------------
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Sent via amsat-bb@xxxxx.xxx. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
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End of AMSAT-BB Digest, Vol 3, Issue 593
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