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CX2SA > SATDIG 28.07.08 00:40l 969 Lines 32333 Bytes #999 (0) @ WW
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Today's Topics:
1. Re: AMSAT-BB Digest, Vol 3, Issue 375 (James Whitfield)
2. Re: Presentations on P3E and the Mars Orbiter P5A (John Heaton)
3. Re: LVB Tracker (Kevin Walsh)
4. ANS-209 AMSAT News Service Weekly Bulletins (JoAnne Maenpaa)
5. FO-29 Over South America (Raul Romero CA3SOC)
6. FO-29 IS on over NA but no one show up! (Luc Leblanc)
7. FO-29 is alive and well (i8cvs)
8. Re: AMSAT-BB Digest, Vol 3, Issue 375 (Art McBride)
9. DELFI-C3 transponder report 09:38 (Rob Hardenberg PE1ITR)
10. Delfi C3 transponder frequencies ? (OZ1MY)
11. FO-29 telemetry (Mike Rupprecht)
12. Re: Presentations on P3E and the Mars Orbiter P5A
(Richard Limebear)
----------------------------------------------------------------------
Message: 1
Date: Sat, 26 Jul 2008 17:04:49 -0500
From: "James Whitfield" <n5gui(AT)cox.net>
Subject: [amsat-bb] Re: AMSAT-BB Digest, Vol 3, Issue 375
To: <amsat-bb(AT)amsat.org>
Message-ID: <001201c8ef6b$9fc77fd0$6401a8c0(AT)Sony2G4>
Content-Type: text/plain; charset="iso-8859-1"
Peter Ellis, vk1kep:
I hope that you will get "better" answers from others of the group that have
practical rather than theoretical experiences with large parabolic
reflectors. My only qualifications on this subject come from experience as
a Geometry teacher and limited amateur astronomy, but for what it is worth,
here are my thoughts.
The simple answer to the necessary "flatness" is better than a quarter
wavelength error. The general idea is that the radio waves you want to
capture come to the "ideal" reflector and all of them bounce back to a focal
point, and all of the waves reaching that point at the same time, that is
"in phase". The error of the real surface translates into a phase shift.
If a substantial surface area is a quarter wave behind the ideal and if an
equal area is a quarter wave in front of the ideal, then the waves from the
two areas will be half wave apart, causing full cancelation. The quarter
wave error is used to indicate that the maximum error difference from a high
point, relative to the ideal, to a low point is no more than a quarter wave.
That way the wave error causes phase shift rather than cancelation.
A greater error probably will provide some "gathering" of the signal, but if
you want to have a parabolic reflector that all of its aperture is
effective, then you need the surface to meet the quarter wave flatness. As
with optics, the less the error, the better the "image" that can be
resolved. As a practical matter on radio frequencies, trying to exceed
quarter wave is not worth the effort.
You did not state if the framework was in good enough shape to serve as a
template for the ideal parabola. If it is not, I can give you a formula,
but I will need more information about the dimensions of the dish.
Best Wishes.
James
n5gui
> Date: Sat, 26 Jul 2008 08:00:26 +1000
> From: Peter Ellis <vk1kep(AT)gmail.com>
> Subject: [amsat-bb] Dish surface 'flatness'
> To: amsat-bb(AT)amsat.org
> Message-ID: <488A4CFA.6060703(AT)gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> I am now the proud owner of a very 'second-hand' 3m mesh-covered
> skeleton dish.
>
> The mesh covering is metaphorical, rather than actual. I watched the
> dish on its back while as a group of small children rolled the dish back
> and forth and trampled holes in the mesh. That's the reason I was able
> to ask for it. "Please take it away," was the manager's reply to my query.
>
> Now, I need to re-mesh the dish, but I need to decide what 'flatness'
> ('true-ness') the surface should be. There has to be a formula, that
> encompasses things like: frequency of operation, curvature or focus
> distance, etc.
>
> I've done some looking online, but can't find it readily.
>
> Suggestions, and discussion, please?
>
> Please note: If you're going to also make product, brand name, or
> supplier suggestions, then be generic as suppliers and products in VK
> (Australia) will differ from where most list members will be sited.
>
> With thanks,
> Peter
> VK1KEP
------------------------------
Message: 2
Date: Sat, 26 Jul 2008 23:58:52 +0100
From: John Heaton <photogr(AT)phers.co.uk>
Subject: [amsat-bb] Re: Presentations on P3E and the Mars Orbiter P5A
To: Joe Westbrook <k7zt(AT)suddenlink.net>
Cc: AMSAT BB <amsat-bb(AT)amsat.org>
Message-ID: <B12D259D-7AD4-430B-9395-E88D5F135BBF(AT)phers.co.uk>
Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes
On 26 Jul 2008, at 18:15, "Joe Westbrook" <k7zt(AT)suddenlink.net> wrote:
> Will the PE3/P5A Presentations be archived and made available for
> those who
> missed the live version?
>
I've created themeni structure for this years presentations on the AUK
website and it will soon (!) be populated with stuff!
Bye for now, John
------------------------------
Message: 3
Date: Sat, 26 Jul 2008 20:40:08 -0400
From: "Kevin Walsh" <kwalsh(AT)datrix.com>
Subject: [amsat-bb] Re: LVB Tracker
To: "'Ronald A. Stunden'" <ve7yc(AT)shaw.ca>, <amsat-bb(AT)amsat.org>
Message-ID: <308540D175834A9D8818A3BC1B384D14(AT)D6502CD1>
Content-Type: text/plain; charset="us-ascii"
No problem, it just lost its mind. Happens to me (not my LVB tracker) all
the time :-).
You just need to recalibrate the rotor and LVB Tracker. It's a simple
process, detailed in the manual at:
http://www.g6lvb.com/Articles/LVBTracker/LVB%20Tracker%20PCB%20Version%201-9
.doc
Good Luck,
Kevin Walsh
W8KHW
-----Original Message-----
From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] On
Behalf Of Ronald A. Stunden
Sent: Saturday, July 26, 2008 1:18 PM
To: amsat-bb(AT)amsat.org
Subject: [amsat-bb] LVB Tracker
Great I just turned on the G5600 and LVB Tracker and getting
"Warning Bad EPROM DATA", Can I try to reload the Eprom or do I
have to order a new one?? Thanks Ron
_______________________________________________
Sent via AMSAT-BB(AT)amsat.org. Opinions expressed are those of the author.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 4
Date: Sat, 26 Jul 2008 20:09:13 -0500
From: "JoAnne Maenpaa" <k9jkm(AT)comcast.net>
Subject: [amsat-bb] ANS-209 AMSAT News Service Weekly Bulletins
To: <amsat-bb(AT)amsat.org>
Message-ID: <000101c8ef85$6293a070$27bae150$(AT)net>
Content-Type: text/plain; charset="us-ascii"
AMSAT NEWS SERVICE
ANS-209
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(AT)amsat.org
***************************************************************
*** 2008 AMSAT Space Symposium and Annual General Meeting ***
*** October 24-26 in Atlanta, Georgia ***
*** http://www.amsat.org/amsat-new/symposium/2008/index.php ***
***************************************************************
In this edition:
* AMSAT-UK Hosts Successful Space Colloquium
* Delfi-C3 Amateur Radio Transponder Activated
* AMSAT 2008 Field Day Summary
* Cal Poly Requesting Beacon Capture Help
* AMSAT Journal Update
* Satellite Shorts From All Over
* ARISS Status Report for the Week of July 21, 2008
SB SAT (AT) AMSAT $ANS-209.01
AMSAT-UK Hosts Successful Space Colloquium
AMSAT News Service Bulletin 209.01
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.01
A successful 23rd AMSAT-UK International Space Colloquium was held
at the University of Surrey, Guildford, England this weekend.
Prof Sir Martin Sweeting, G3YJO Chairman AMSAT-UK, opened the
Colloquium on Friday. This was followed by the keynote speech given
by Dr Rob Gowen, Department of Space & Climate Physics (Mullard
Space Science Laboratory, University College London and Coordinator
of the UK Lunar Penetrator Consortium) on "Science Penetrators
for the UK MoonLITE mission".
On Saturday the Delfi-C3 team gave a presentation on their exciting
new satellite. Its SSB/CW 435/145 linear transponder will activated
soon and is sure to prove popular with satellite enthusiasts world-
wide.
Saturday's Colloquium schedule also included presentations from
AMSAT-DL on both the eagerly awaited P3E High Earth Orbiting satel-
lite and the pioneering Mars Orbiter P5A. This will be the first
private venture spacecraft to travel to the Red Planet providing
Radio Amateurs with some true DX signals.
A complete listing of the Colloquium Technical program can be found
at: http://www.uk.amsat.org/content/view/640/213/
The IARU Satellite Forum chaired by the IARU Satellite Adviser Hans
van de Groenendaal ZS6AKV also met during the Colloquium weekend.
The main topic included Band planning for satellite operations on
frequencies in the Amateur Service.
The Colloquium included a live webcast of the proceedings via
http://www.batc.tv/. There was a Live Chat page available to enable
web viewers to post messages.
[ANS thanks Trevor, M5AKA and AMSAT-UK for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.02
Delfi-C3 Amateur Radio Transponder Activated
AMSAT News Service Bulletin 209.02
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.02
The Delfi team activated the Amateur Radio 435 to 145 MHz linear
transponder onboard the satellite activated just before they left
the Netherlands to attend the AMSAT-UK Colloquium which was held
July 25-27 at the University of Surrey in Guildford, England.
The Amateur Radio satellite Delfi-C3 (DO-64), built at the Delft
University of Technology in the Netherlands, was launched in April.
Since then it has been collecting educational research data for use
by the university students with the assistance of Radio Amateurs
around the world.
Members of the Delfi-C3 team gave presentations during the Colloquium
about their exciting new Amateur Radio satellite.
The transponder can be accessed with these frequencies:
Transponder mode beacon: 145.870 MHz CW
Linear transponder downlink: 145.880 - 145.920 MHz
Linear transponder uplink: 435.570 - 435.530 MHz
All frequencies are +/- Doppler shift that can be up to 3 kHz at
145 MHz. As it's an inverting transponder a LSB signal on the uplink
would be translated to a USB signal on the downlink.
The transponder mode was switched on during this weekend whenever it
was within range of Europe and automatically switched back to science
(telemetry) mode when it entered eclipse about 1 hour later.
Rob, PE1ITR reported from the Netherland on Saturday, July 26, "Today
I made my first QSO around 10:53UTC and worked HA2RD with 5x7 signals.
I also heard F5ETM."
Alan, ZL2BX said, "The transponder was on over ZL this morning 2036UT
pass with weak signals from transponder downlink and beacon. It was
active again on the 2212UT pass with very good signals from both trans-
ponder downlink and beacon."
More information on this satellite can be found at:
Delfi-C3: http://www.delfic3.nl/
Delfi-C3 Videos on YouTube can be found at:
http://www.youtube.com/user/DelfiC3
[ANS thanks the Delfi-C3 Team and AMSAT-UK for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.03
AMSAT 2008 Field Day Summary
AMSAT News Service Bulletin 209.03
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.03
AMSAT Director Contests and Awards Bruce Paige, KK5DO, provided an
executive summary of participation in the 2008 AMSAT Field Day.
The results will be published in the July/August AMSAT Journal. This
includes some really nice photos that were sent in. Detailed results
will also be posted in an ANS bulletin.
This year, we had 8 satellites used. There was even one QSO on AO-16.
A total of 120 QSO's were reported and we had 17 stations submit
scores. The most contacts were done on VO-52 this year. Behind that
was AO-7.
Here are some statistics from this year and previous years:
2005 2006 2007 2008
Satellites 8 7 5 8
QSO's 120 258 207 220
Stations 11 21 13 17
Watch your mailbox for your copy of the AMSAT Journal and standby for
more Field Day news via ANS.
[ANS thanks Bruce, KK5DO for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.04
Cal Poly Requesting Beacon Capture Help
AMSAT News Service Bulletin 209.04
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.04
Jason Anderson, KI6GIV, at California Polytechnic State University is
requesting amateur radio operators worldwide to assist with capturing
the telemetry of the Cal Poly CP4 satellite.
Jason wrote, "We have seen some unpredictable behavior on our satellite,
CP4. Since we only have contact with the satellite once every 12 hours,
it would be extremely helpful if we could get some global support with
collecting beacons to get a more complete picture of the the satellite's
health."
Please send any collected data (audio or decoded binary) via email to:,
jander06(AT)calpoly.edu
Satellite Link Information
------------------------------
Frequency: 437.325Mz
Modulation: FSK (but uses LSB cheat to make AFSK)
Radio Mode: LSB (neccesary for LSB cheat)
Baud Rate: 1200
Beacon rate: 1 beacon/minute (maybe change to 5 minutes if satellite changes
mode)
[ANS thanks Jason, KI6GIV for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.05
AMSAT Journal Update
AMSAT News Service Bulletin 209.05
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.05
AMSAT Journal Editor, Ed Long, WA4SWJ reported that the next issue of
the Journal has been delivered to the printer and will be on its way
to your mailbox soon.
Ed reminds members to get busy, "I am PAST DUE for articles for the
next issue. If you have an article you would like to submit to the
Journal please send it as soon as you can to:
journal at amsat dot org."
[ANS thanks Ed, WA4SWJ for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.06
Satellite Shorts From All Over
AMSAT News Service Bulletin 209.06
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.06
+ The European Space Agency has announced the commencement of payload
selection for VERTA-1, the Vega second flight. The primary objective
of the VERTA-1 mission is to demonstrate the multiple-payload capa-
bility of the Vega launch system into a low-Earth, Sun-synchronous
orbit in the 500-800 km altitude range. Payload opportunities are
open to any private or public entity, without restriction as to
nationality. For more information see:
http://www.esa.int/SPECIALS/Launchers_Home/SEM3MKXIPIF_0.html
+ FO-29 has been only turned on over Japan for several months as the
ground controllers worked on battery power managment to conserve
this satellite for as long as possible. This past week several
reports have been received that FO-29 has been heard over most of
its orbit in other parts of the world. Frank, VK5MFW reported
contacts with ZL2BX and ZL1BVA. Mak, SV1BSX reported a contact
with SW1JGW and DL6HP. Users are encouraged to continue to be
careful with this satellite's power budget and cease operation
if the downlink signal weakens or experiences FM shifting.
[ANS thanks everyone for the above information]
/EX
SB SAT (AT) AMSAT $ANS-209.07
ARISS Status Report for the Week of July 21, 2008
AMSAT News Service Bulletin 209.07
>From AMSAT HQ SILVER SPRING, MD.
July 27, 2008
To All RADIO AMATEURS
BID: $ANS-209.07
1. School Contacts
European Space Camp 2008 held at the Zanka Children and Youth Centre
in Zanka, Hungary for the children of ESA employees. had an ARISS
contact on Thursday, July 24. The Hungarian Astronautical Society
(HAS) organized the event. The Radio Club of the Puskas Polytechnic
(HA5KHC) provided equipment and support the contact.
United Space School in Seabrook, Texas is slated for an ARISS contact
on Wednesday, July 30 via the telebridge station ON4ISS in Belgium.
These students come from around the world for a two week session,
during which they stay with local host families while being mentored
by astronauts, engineers, and scientists to design a mission to Mars
as their team project. Class sessions are held at the University of
Houston at Clear Lake.
2. Kuwait Science Club Contact Successful
On Monday, July 14, youth attending the Kuwait Science Club participated
in an ARISS contact via the telebridge station WH6PN in Hawaii. Greg
Chamitoff, KD5PKZ, answered 16 questions posed to him by 12 children
and was answering the 17th question when the signal faded out. The
audio from this event was fed into the EchoLink AMSAT (101 377) con-
ference room server which received 11 connections from 3 countries.
It was also fed into the EchoLink JK1ZRW (277 208) server and into
the IRLP Discovery Reflector 9010. More information and the audio file
may be found on the ARISS-Europe Web site.
See: http://www.ariss-eu.org/2008_07_15.htm
3. ARISS TIM
The ARISS team is meeting in Moscow this week for a Technical Interchange
Meeting (TIM). The conference will be held July 21-23.
[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,
JoAnne Maenpaa, K9JKM
K9JKM at amsat dot org
------------------------------
Message: 5
Date: Sat, 26 Jul 2008 21:23:56 -0400
From: "Raul Romero CA3SOC" <ce3soc(AT)gmail.com>
Subject: [amsat-bb] FO-29 Over South America
To: <amsat-bb(AT)amsat.org>, <rm2642(AT)aol.com>
Message-ID: <FA5770F4DC7D491391801E289746E55A(AT)p42800>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Very nice copy in South America CHILE FO-29
Station from Argentina and Brazil Copy
TNX Team for FO-29
73
Raul
CE3RR And CA3SOC
---------------------------------------------------------------------
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----- Original Message -----
From: <rm2642(AT)aol.com>
To: <amsat-bb(AT)amsat.org>
Sent: Saturday, July 26, 2008 2:51 PM
Subject: [amsat-bb] FO-29
> Northerly pass?footprint was coast to coast but only three users?counting
> myself. FO-29 works?great on SSB. Thanks to JARL.
> Ron
> N6PAA
> _______________________________________________
> Sent via AMSAT-BB(AT)amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 6
Date: Sat, 26 Jul 2008 21:23:05 -0400
From: Luc Leblanc <lucleblanc6(AT)videotron.ca>
Subject: [amsat-bb] FO-29 IS on over NA but no one show up!
To: amsat-bb(AT)amsat.org
Cc: eu-amsat(AT)yahoogroups.com
Message-ID: <488B95B9.17963.3436C97(AT)lucleblanc6.videotron.ca>
Content-Type: text/plain; charset=US-ASCII
I called on 3 passes today on FO-29 but no one shows up. Signal was very
stable and clean but i suspect the TX was running at QRP level i
only got a S2 reading with the INT preamp on on the FT-847!
Anyway it's another one the be anchored on to avoid driftingachonred out of
the channel. DELFI C-3 will be the next one.
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 7
Date: Sun, 27 Jul 2008 06:08:07 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] FO-29 is alive and well
To: "AMSAT-BB" <amsat-bb(AT)amsat.org>
Cc: Francesco Grappi <f.grappi(AT)vodafone.it>
Message-ID: <004101c8ef9e$60c12100$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
Hi All,
Following suggestions of my friend Mak, SV1BSX I tried FO-29 this
night 27 july during the South bound orbit 58978 when the AOS for me
in JN70ES was at 00:06 UTC and FO-29 was in sun light.
I was alone into the passband and my return signal was very strong above
my noise floor with appoximately only 10 watt on a 13 dBi crossed yagi
RHCP / LHCP (about 200 watt EIRP)
The SSB return was very clean and without FMing with the usual need to
switch RHCP to LHCP time to time to get the best signal strength
At 00:15 UTC FO-29 started to experience the eclipse as per InstanTrack
but no signe of reduction of my return signal or FMing was noted.
>From 00:15 to 00:21 until my LOS the satellite was over Africa and well
in full eclipse for about 6 minutes but my own return signal was still clear
ad strong without any signe of FMing so that it seems that the battery are
working and as far I know the satellite performance seems to be nominal.
The CW beacon was ON all the time but it should be necessary to
decode the TLM to get the actual parameters ( I think IW4DVZ can do
the job with his suitable software )
The transponder is very sensitive as it was as new so that refrain please
to use high power because 200 watt EIRP is more than necessary.
I tanks very much Mak SV1BSX for sending to me the results of his
experience yesterday confirming the results that I got this night both
confirming that FO-29 seems to be alive and well.
We don't know what JARL did to resurrex this beautiful satellite but
until she will last we have another real CW and SSB satellite to work.
Congratulations to JARL
73" de
i8CVS Domenico
------------------------------
Message: 8
Date: Sat, 26 Jul 2008 21:18:57 -0700
From: "Art McBride" <kc6uqh(AT)cox.net>
Subject: [amsat-bb] Re: AMSAT-BB Digest, Vol 3, Issue 375
To: "'James Whitfield'" <n5gui(AT)cox.net>, <amsat-bb(AT)amsat.org>
Message-ID: <000301c8ef9f$e3d75e00$0200a8c0(AT)kc6uqh>
Content-Type: text/plain; charset="us-ascii"
Peter,
A dent in dish parabola is just one factor.
You also need to consider
1. Overall parabola shape.
2. Feed choice for best illumination.
3. Feed Alignment.
In a well designed dish antenna the efficiency rarely is greater than 50%
(-3 dB from ideal) Spending a little time learning how a dish works and all
the considerations will give you a far better antenna.
Art,
KC6UQH
-----Original Message-----
From: amsat-bb-bounces(AT)AMSAT.Org [mailto:amsat-bb-bounces(AT)AMSAT.Org] On
Behalf Of James Whitfield
Sent: Saturday, July 26, 2008 3:05 PM
To: amsat-bb(AT)AMSAT.Org
Subject: [amsat-bb] Re: AMSAT-BB Digest, Vol 3, Issue 375
Peter Ellis, vk1kep:
I hope that you will get "better" answers from others of the group that have
practical rather than theoretical experiences with large parabolic
reflectors. My only qualifications on this subject come from experience as
a Geometry teacher and limited amateur astronomy, but for what it is worth,
here are my thoughts.
The simple answer to the necessary "flatness" is better than a quarter
wavelength error. The general idea is that the radio waves you want to
capture come to the "ideal" reflector and all of them bounce back to a focal
point, and all of the waves reaching that point at the same time, that is
"in phase". The error of the real surface translates into a phase shift.
If a substantial surface area is a quarter wave behind the ideal and if an
equal area is a quarter wave in front of the ideal, then the waves from the
two areas will be half wave apart, causing full cancelation. The quarter
wave error is used to indicate that the maximum error difference from a high
point, relative to the ideal, to a low point is no more than a quarter wave.
That way the wave error causes phase shift rather than cancelation.
A greater error probably will provide some "gathering" of the signal, but if
you want to have a parabolic reflector that all of its aperture is
effective, then you need the surface to meet the quarter wave flatness. As
with optics, the less the error, the better the "image" that can be
resolved. As a practical matter on radio frequencies, trying to exceed
quarter wave is not worth the effort.
You did not state if the framework was in good enough shape to serve as a
template for the ideal parabola. If it is not, I can give you a formula,
but I will need more information about the dimensions of the dish.
Best Wishes.
James
n5gui
> Date: Sat, 26 Jul 2008 08:00:26 +1000
> From: Peter Ellis <vk1kep(AT)gmail.com>
> Subject: [amsat-bb] Dish surface 'flatness'
> To: amsat-bb(AT)amsat.org
> Message-ID: <488A4CFA.6060703(AT)gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> I am now the proud owner of a very 'second-hand' 3m mesh-covered
> skeleton dish.
>
> The mesh covering is metaphorical, rather than actual. I watched the
> dish on its back while as a group of small children rolled the dish back
> and forth and trampled holes in the mesh. That's the reason I was able
> to ask for it. "Please take it away," was the manager's reply to my query.
>
> Now, I need to re-mesh the dish, but I need to decide what 'flatness'
> ('true-ness') the surface should be. There has to be a formula, that
> encompasses things like: frequency of operation, curvature or focus
> distance, etc.
>
> I've done some looking online, but can't find it readily.
>
> Suggestions, and discussion, please?
>
> Please note: If you're going to also make product, brand name, or
> supplier suggestions, then be generic as suppliers and products in VK
> (Australia) will differ from where most list members will be sited.
>
> With thanks,
> Peter
> VK1KEP
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Message: 9
Date: Sun, 27 Jul 2008 11:52:27 +0200 (CEST)
From: "Rob Hardenberg PE1ITR" <rob(AT)itr-datanet.com>
Subject: [amsat-bb] DELFI-C3 transponder report 09:38
To: amsat-bb(AT)amsat.org
Message-ID:
<34237.62.194.134.114.1217152347.squirrel(AT)customer.itr-datanet.com>
Content-Type: text/plain;charset=iso-8859-1
Hi All,
I saw the delfi-c3 command team on video from the uk amsat weekend sitting
with the laptop while
the sat was on AOS. My thought: They are switching on the transponder! And yes
:-)
wkd: DL1YDD, OZ1MY, IW5EJM and DG0ER
Great signals! Sometimes Freq Modulaton on the downlink signals
73 Rob PE1ITR
http://www.pe1itr.com
------------------------------
Message: 10
Date: Sun, 27 Jul 2008 11:57:15 +0200
From: "OZ1MY" <oz1my(AT)privat.dk>
Subject: [amsat-bb] Delfi C3 transponder frequencies ?
To: "AMSAT-BB" <amsat-bb(AT)AMSAT.Org>
Message-ID: <000501c8efcf$26c25d80$6401a8c0(AT)opasia.dk>
Content-Type: text/plain; charset="iso-8859-1"
Hi all,
The transponder was working at the pass with AOS at
0926 UTC here in Copenhagen.
Had a couple of QSOs with HA2RD and PE1ITR.
As far as I can make out the frequencies are different
from the published ones.
Just after the transponder was turned on I har to go
to an uplink of 435.565 MHz to get 145.900 MHz down.
This is the nominal pair I used in SatPC32.
After some time had to adjust the uplink down to
435.563 MHz.
Can someone confirm this ?
73 OZ1MY
Ib
------------------------------
Message: 11
Date: Sun, 27 Jul 2008 16:34:44 +0200
From: "Mike Rupprecht" <mail(AT)mike-rupprecht.de>
Subject: [amsat-bb] FO-29 telemetry
To: "'AMSAT-BB'" <amsat-bb(AT)amsat.org>
Message-ID: <002801c8eff5$ea651c20$bf2f5460$(AT)de>
Content-Type: text/plain; charset="us-ascii"
Hi all,
FO-29 CW telemetry at 1210 UTC, July 27th
1210 UTC
hihi 22e288d58f050525002401016a629695b07bb9b4babcb7
hihi 22e288d58f050525002401016b629695b076b9b4babcb7
hihi 22e288d58f050525002401017f629594b077b8b4babbb7
hihi 22e288d58f0505250024010183629595b19eb8b4babbb7
hihi 22e288d58f0505250024010184629594b165b8b4babbb7
hihi 22e288d58f0505250024010186629695b075b8b4b9bbb7
hihi 22e288d58f0505250024010182629595b054b7b3b9bab7
hihi 22e288d58f050525002401017c629594b09bb7b3b9bab7
Solar Current 1313.7 [mA]
Battery Current 79.2 [mA]
Battery Voltage 16.1 [V]
Middle Voltage 7.2 [V]
Bus Voltage 17.3 [V]
JTA Tx Power 662.4 [mW]
Structure1 Temp 10.4 [C]
Structure2 Temp 12.0 [C]
Structure3 Temp 10.0 [C]
Structure4 Temp 9.3 [C]
Battery Cell Temp 10.8 [C]
73, Mike
DK3WN
Von: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] Im
Auftrag von i8cvs
Gesendet: Sonntag, 27. Juli 2008 06:08
An: AMSAT-BB
Cc: Francesco Grappi
Betreff: [amsat-bb] FO-29 is alive and well
Hi All,
Following suggestions of my friend Mak, SV1BSX I tried FO-29 this
night 27 july during the South bound orbit 58978 when the AOS for me
in JN70ES was at 00:06 UTC and FO-29 was in sun light.
I was alone into the passband and my return signal was very strong above
my noise floor with appoximately only 10 watt on a 13 dBi crossed yagi
RHCP / LHCP (about 200 watt EIRP)
The SSB return was very clean and without FMing with the usual need to
switch RHCP to LHCP time to time to get the best signal strength
At 00:15 UTC FO-29 started to experience the eclipse as per InstanTrack
but no signe of reduction of my return signal or FMing was noted.
>From 00:15 to 00:21 until my LOS the satellite was over Africa and well
in full eclipse for about 6 minutes but my own return signal was still clear
ad strong without any signe of FMing so that it seems that the battery are
working and as far I know the satellite performance seems to be nominal.
The CW beacon was ON all the time but it should be necessary to
decode the TLM to get the actual parameters ( I think IW4DVZ can do
the job with his suitable software )
The transponder is very sensitive as it was as new so that refrain please
to use high power because 200 watt EIRP is more than necessary.
I tanks very much Mak SV1BSX for sending to me the results of his
experience yesterday confirming the results that I got this night both
confirming that FO-29 seems to be alive and well.
We don't know what JARL did to resurrex this beautiful satellite but
until she will last we have another real CW and SSB satellite to work.
Congratulations to JARL
73" de
i8CVS Domenico
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------------------------------
Message: 12
Date: Sun, 27 Jul 2008 18:28:44 +0100
From: Richard Limebear <Richard(AT)g3rwl.demon.co.uk>
Subject: [amsat-bb] Re: Presentations on P3E and the Mars Orbiter P5A
To: amsat-bb(AT)amsat.org
Message-ID: <488CB04C.9050002(AT)g3rwl.demon.co.uk>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Joe Westbrook wrote:
> Will the PE3/P5A Presentations be archived and made available for those who
> missed the live version?
Good news: Yes. Bad news: its gonna take a few weeks to edit the video
stream and extract the individual presentations. (Plus, the 'owner' of
the server where they are stored is away on holiday.)
--
73
Richard W L Limebear G3RWL
g3rwl(AT)amsat.org
FOC # 1188
So many beautiful girls ... (sob) so little time
------------------------------
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End of AMSAT-BB Digest, Vol 3, Issue 378
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