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CX2SA > SATDIG 06.05.08 00:37l 820 Lines 25977 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. AO 51 mode L/S (ik1sow)
2. AO-16 currently silent and resting 11:15UTC 5May2008
(Mark L. Hammond)
3. Re: Happy Birthday HAMSAT (i8cvs)
4. SEEDS II REC 6 (Raul Romero CA3SOC)
5. DELFI decoded (ji1izr/Masahiro SANADA)
6. UT1FG/mm report (Robert Turlington)
7. FCAL alive May, 05 (Edward Chuang)
8. Re: DELFI decoded (Viktor Kudielka)
9. AO-51 LS Mode (Rm2642(AT)aol.com)
10. Re: Creating Artworks based on Delfi-C3... or ? (i8cvs)
11. Re: SEEDS, Cute-1.7+APDII and COMPASS-1 over West Malaysia
(Luc Leblanc)
12. Cute-1.7+APD and Compass-1 over West Malaysia
(Sion Chow Q. C. (9W2QC))
13. Re: Creating Artworks based on Delfi-C3... or ?
(Wouter Jan Ubbels)
14. Re: AO-16 currently silent and resting 11:15UTC 5May2008
(George Henry)
----------------------------------------------------------------------
Message: 1
Date: Mon, 5 May 2008 10:46:59 +0200
From: "ik1sow" <ik1sow(AT)tele2.it>
Subject: [amsat-bb] AO 51 mode L/S
To: <amsat-bb(AT)amsat.org>
Message-ID: <000801c8ae8c$95797a80$6401a8c0(AT)ik1sowie4ygro6>
Content-Type: text/plain; charset="windows-1252"
Good Morning all...
AO 51 in mode L/S working great, i make qso with Willi OE6AG in JN76 during
the pass at 0835 utc with max elev. of 21 degrees, signal from downlink was
over 9.
73'' de Lino IK1SOW (JN35)
--
Io utilizzo la versione gratuita di SPAMfighter per utenti privati. Sino ad
ora
ha rimosso 117 mail spam.
Gli utenti paganti non hanno questo messaggio nelle loro email .
Prova gratuitamente SPAMfighter qui:http://www.spamfighter.com/lit
------------------------------
Message: 2
Date: Mon, 05 May 2008 07:33:42 -0400
From: "Mark L. Hammond" <n8mh(AT)embarqmail.com>
Subject: [amsat-bb] AO-16 currently silent and resting 11:15UTC
5May2008
To: amsat-bb(AT)amsat.org
Message-ID: <9E.FE.10714.690FE184(AT)smtp07.embarq.synacor.com>
Content-Type: text/plain; charset="us-ascii"
Hello all,
The weekend presented a chance to gather some telemetry on AO-16. The
telemetry looks nominal. Recently, the satellite seems to go silent on a
nearly daily basis. Increasing eclipse periods remain a likely explanation,
but we remain open to other explanations at this point.
To this end, I have turned AO-16 OFF for a few days to rest and ensure that
its batteries will be given a chance to become fully charged. Following its
several day rest period, we'll try to conduct more tests to better determine
what type of operations that AO-16 is currently able to support.
Please do not transmit to AO-16 until further notice.
73 on behalf of the command team (and Happy Cinco de Mayo!),
Mark L. Hammond [N8MH]
------------------------------
Message: 3
Date: Mon, 5 May 2008 14:29:29 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: Happy Birthday HAMSAT
To: "Prathap Kumar" <vu2pop(AT)gmail.com>, "amsatindia(AT)yahoogroups."
<amsatindia(AT)yahoogroups.com>, "AMSAT-BB" <amsat-bb(AT)amsat.org>
Message-ID: <006b01c8aeab$aa7fc500$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Prathap Kumar" <vu2pop(AT)gmail.com>
To: "amsatindia(AT)yahoogroups." <amsatindia(AT)yahoogroups.com>;
<amsat-bb(AT)amsat.org>
Sent: Monday, May 05, 2008 6:03 AM
Subject: [amsat-bb] Happy Birthday HAMSAT
> Wishing HAMSAT VO-52 a Very Happy Birthday
> and many more to come with good health and service to all Hams.
> Its 3 years old and doing well.
> Happy Hamsating
> Best 73
> Pop
> VU2POP
> Secy Amsat India
Hi Pop , VU2POP
Congrats to Amsat India ! Actually VO-52 along with OSCAR-7 are the
only satellites with a linear transponder for multiaccess CW and SSB
communications.
73" de
i8CVS Domenico
------------------------------
Message: 4
Date: Mon, 5 May 2008 09:11:41 -0400
From: "Raul Romero CA3SOC" <ce3soc(AT)gmail.com>
Subject: [amsat-bb] SEEDS II REC 6
To: "Amsat-BB(AT)Amsat.Org" <amsat-bb(AT)amsat.org>
Message-ID: <CAF6B13C5A484C63B9BC15BD191F7171(AT)p42800>
Content-Type: text/plain; charset="iso-8859-1"
now Files number is Recorded with my Yaesu FRG-9600
cat system for dopler trx manager Demo only and Satscape
pse check sound and pic now file 6 from todoy 12:05 UTC Over CHILE
My Antenna is Yagui 7 Elem Fixed 30 Elev And Rotator Convencional
20 Meter for Coaxil 10 Meter RG-213 + 10 Meter Belden 9913
73 Raul
CA3SOC
http://ce3soc.no-ip.org
PC Server For Files SEED And Other
---------------------------------------------------------------------
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There is a solution!"
Protected by GIANT Company's Spam Inspector
The most powerful anti-spam software available.
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------------------------------
Message: 5
Date: Mon, 5 May 2008 22:00:30 +0900
From: "ji1izr/Masahiro SANADA" <ji1izr(AT)jamsat.or.jp>
Subject: [amsat-bb] DELFI decoded
To: "AMSAT" <amsat-bb(AT)amsat.org>
Message-ID: <001601c8aeb0$d6903030$abcfa8c0(AT)hamateurh6ixw2>
Content-Type: text/plain; charset="iso-2022-jp"
Dear everyone,
I finally decoded DELFI by RASCAL.
It is very difficult to tune for decoding.
I got only 2 packets.
Masahiro Sanada
JI1IZR
***************************
Masahiro Sanada
de ji1izr
Hiratsuka-city
Kanagawa,Japan
ji1izr_1975(AT)nifty.com
ji1izr(AT)jarl.com
ji1izr(AT)jamsat.or.jp
web: http://ji1izr.atnifty.com/
blog: http://ji1izr.air-nifty.com/
***************************
------------------------------
Message: 6
Date: Mon, 5 May 2008 14:19:47 +0100
From: Robert Turlington <rob_g8ate(AT)hotmail.com>
Subject: [amsat-bb] UT1FG/mm report
To: Amsat Buleitin Board <amsat-bb(AT)amsat.org>
Message-ID: <BAY112-W18FCDD3252E132CB74EE4FC0D70(AT)phx.gbl>
Content-Type: text/plain; charset="iso-8859-1"
Worked Yuri UT1FG/mm on VO52 15mins ago when he was in GM94 mid atlantic this
may well be the last time I am able to contact him but will try again
tomorrowRegards Robert G8ATE in Io92JP
_________________________________________________________________
All new Live Search at Live.com
http://clk.atdmt.com/UKM/go/msnnkmgl0010000006ukm/direct/01/
------------------------------
Message: 7
Date: Mon, 05 May 2008 22:21:58 +0800
From: Edward Chuang <edward.yhi(AT)gmail.com>
Subject: [amsat-bb] FCAL alive May, 05
To: amsat-bb(AT)amsat.org
Message-ID: <481F1806.6000402(AT)anet.net.tw>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hello,
FCAL packet copied at May,05 14:01 UTC over PL04vq:
14:01 KD4HBO/TELEM>TELEM>UI,C,F0:
02960593FFFE00B8FFFFFFE8FFFE0090FFFEFFE0FFFE0048FFFEFE40
14:01 KD4HBO/TELEM>TELEM>UI,C,F0:
Analog 0004000100F800DA00A700FE00DF0010 N 0000001E
73
Edward / BX1AD
-----
------------------------------
Message: 8
Date: Mon, 5 May 2008 15:47:34 +0000
From: Viktor Kudielka <viktor.kudielka(AT)ieee.org>
Subject: [amsat-bb] Re: DELFI decoded
To: ji1izr/Masahiro SANADA <ji1izr(AT)jamsat.or.jp>
Cc: AMSAT <amsat-bb(AT)amsat.org>
Message-ID: <20080505154734.GA19403(AT)saturn.oe1kib.ampr.org>
Content-Type: text/plain; charset=us-ascii
On Mon, May 05, 2008 at 10:00:30PM +0900, ji1izr/Masahiro SANADA wrote:
> Dear everyone,
>
> I finally decoded DELFI by RASCAL.
> It is very difficult to tune for decoding.
> I got only 2 packets.
>
> Masahiro Sanada
> JI1IZR
> ***************************
> Masahiro Sanada
> de ji1izr
> Hiratsuka-city
> Kanagawa,Japan
> ji1izr_1975(AT)nifty.com
> ji1izr(AT)jarl.com
> ji1izr(AT)jamsat.or.jp
> web: http://ji1izr.atnifty.com/
> blog: http://ji1izr.air-nifty.com/
> ***************************
Masahiro-san,
For tuning a waterfall spectrum display is very, very useful.
I am running WSJT6 with the SpecJT window in parallel to RASCAL
and I copied during this first week nearly 1200 packets.
Vy 73,
Viktor OE1VKW
--
Viktor Kudielka
e-mail: viktor.kudielka(AT)ieee.org,oe1vkw(AT)amsat.org,oe1vkw(AT)oevsv.at
S-mail: Peter Jordan Str.165 A-1180 Vienna AUSTRIA
Tel:+43-1-470-9342 URL: http://ostarrichi.ch/viktor/
AMSAT-NA LM-240;AMSAT-UK;AMSAT-DL;OeVSV
------------------------------
Message: 9
Date: Mon, 5 May 2008 12:28:29 EDT
From: Rm2642(AT)aol.com
Subject: [amsat-bb] AO-51 LS Mode
To: amsat-bb(AT)amsat.org
Message-ID: <d31.2d008875.35508fad(AT)aol.com>
Content-Type: text/plain; charset="US-ASCII"
Did not hear anybody on AO-51 LS mode this morning pass 5 May 1512Z. Could
be I have a weak setup?
Using M2 yagi 23CM35EZ uplink (9 watts out) and 14 turn helix on downlink
with 2400-144 downconverter.
SatPC32 Doppler.SQF file set at
AO-51,2401200.0,1268700,FM,FM,NOR,2256000.0,0.
Downlink offset frequency seems okay as shown on my Yaesu FT-736R.
Ron
n6paa
**************Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
------------------------------
Message: 10
Date: Mon, 5 May 2008 18:37:39 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: Creating Artworks based on Delfi-C3... or ?
To: "Henk, PA3GUO" <hamoen(AT)iae.nl>, "AMSAT-BB" <amsat-bb(AT)amsat.org>
Cc: pa3guo(AT)amsat.org
Message-ID: <001a01c8aece$55b54c20$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Henk, PA3GUO" <hamoen(AT)iae.nl>
To: <amsat-bb(AT)amsat.org>
Cc: <pa3guo(AT)amsat.org>
Sent: Monday, May 05, 2008 6:42 AM
Subject: [amsat-bb] Creating Artworks based on Delfi-C3... or ?
> Dear all,
>
> Previous days it was observed already, then in periods of maximum signal
> strengths on LHCP, there is a minimum on RCHP (and visa versa).
> Triggered by that I wanted to try something else: simulations reception
> of the two antennas of my 'X' antenna (2x6 elements DK7ZB), and plot the
> signal strengths over time.
>
> Most likely this can be considered as a totally useless experiment, but
> I wanted to do this for once (could have taken another satellite as well).
> Both antennas are only 6 cm distance from eachother, which is compensated
> by a bit of extra coax cable. The two cables enter the shack.
>
> One cable has been connected to an FT817. Other cable was connected to
> an TS2000. Using this set-up I did a simulatious reception of Delfi C3,
> and plotted the received signals above eachother:
> Result: Maximum on one antenna is minimum on the other, and visa versa.
>
> Have a look yourself at the graph:
>
http://home.vianetworks.nl/users/hamoen/pa3guo/dc3_04may08_2000utc_pa3guo_po
larization_145.930.jpg
>
> Conclusion of PA3GUO: fun to do, but I have no clue what this tells us :-)
> Conclusion of PE1ITR: it's beautiful, but one does not know what one can
do with it... it's ART ! :-)
>
> ... still:
> - if Delfi C3 has circular polarization, shouldn't both signals have been
the same ?
> - how does this relate to the LCHP/RCHP opposite maximums (see text above)
?
>
> Looking forward for your thoughts !
>
> 73, Henk, PA3GUO
> http://www.qsl.net/pa3guo
>
Hi Henk, PA3GUO
Delfi-C3 is transmitting circularly polarized no matter if RHCP or LHCP
because it depend on which side the satellite look at your antennas and
more on this later.
As you stated you are receiving with an "X" antenna made of two linearly
polarized antennas one is oriented at 45? "/" and the other one at 135? "\"
The point here is that the transmitting antenna of Delfi-C3 is not looking
straight boreside at any time to your receiving antennas because the
satellite is slowly tumbling.
If we assume that at a certain time the transmitting and receiving antennas
have been randomly looking straight at each other (coaxial) then a
circularly polarized wave will appear circularly polarized with the same
amplitude into your "X" antennas.
If the antennas are not looking directly at each other because there is a
continuously variable squint angle with the satellite tumbling then a
circularly polarized wave will appear elliptical to your linearly receiving
"X" antennas.
This effect is easily visualized if you look at a phonograph record ;
looking directly onto the playing surface , it appears round .As the record
(the satellite CP antenna) is rotated toward an edgewiseview ,it appears
more and more elliptical until, when you are looking directly at the edge
of the record, it appears as a straight line.
This effect can be applied here and when your two crossed linearly polarized
"X" antennas are looking directly into a circularly polarized antenna, the
X components are equal:As one moves around to the edge of the antennas
(satellite tumbling) one of the X linear components increases while the
other X component decreases or approaches to zero.
If the linear component that appears as a straight line is oriented exactly
at 45? "/" with respect to your "X" antennas then the signal received by the
45? "/" antenna is maximum while the signal received by the 135? "\"
antenna is minimum or zero.
Your question 1 :
if Delfi C3 has circular polarization, shouldn't both signals have been the
same ?
My answer 1 :
They are the same strenght only when Delfi C3 and your "X" antennas are
looking straight at each other.
Your question 2 :
how does this relate to the LCHP/RCHP opposite maximums (see text above ) ?
My answer 2 :
If you are receiving a LHCP or RHCP wave with an "X" linearly polarized
antenna the signals is the same but if you receive with a CP antenna the
effect changes.
The antenna of Delfi C3 is made with 2 crossed elements located in the same
plane.
To generate circular polarization one element must be feed with a 90? phase
difference.
Been the crossed elements in the same plane without any reflector the
antenna radiates RHCP in one axial direction and LHCP in the other
direction.
If you receive with a circularly polarized antenna it happens that depending
on wich face the satellite is looking to your "X" antennas you can receive a
RHCP or a LHCP wave and this is why a polarization switcher is necessary.
I have extracted this basic concept from " The Advantages of Circular
Polarization for Amateur Satellite Ground Stations" by John J. Nagle, K4KJ
publisched into the "1975 ARRL Technical Symposium" page 80-87 of text
with 25 pages for drawings and pictures.
73" de
i8CVS Domenico
------------------------------
Message: 11
Date: Mon, 05 May 2008 07:17:02 -0400
From: Luc Leblanc <lucleblanc6(AT)videotron.ca>
Subject: [amsat-bb] Re: SEEDS, Cute-1.7+APDII and COMPASS-1 over West
Malaysia
To: amsat-bb(AT)AMSAT.Org
Message-ID: <481EB46E.13880.B5C72(AT)lucleblanc6.videotron.ca>
Content-Type: text/plain; charset=US-ASCII
On 5 May 2008 at 12:30, Sion Chow Q. C. (9W2QC) wrote:
> Dear All,
>
>
>
> Pass report for SEEDS, Cute-1.7+APDII and COMPASS-1 over West Malaysia
>
>
>
> Time: 1054 Local or 0254 UTC
>
> Max Elevation: 55 degrees
>
> Satellites: Cute-1.7+APDII & COMPASS-1
>
>
>
> http://www.9w2qc.net/amsatbb/cute05may1054.mp3
>
>
>
> After 3 minutes, QSYed to SEEDS which was in digitalker mode. Below is the
> best SSTV picture from SEEDS. Can anyone explain why the image is still
> noisy despite a full quieting 59+10db signal (with preamp on)?
>
>
>
The problem came from the background waves pattern as it was coming from an
unregulated voltage or something is added in the signal from
the original recording? I checked this week end on HF some SSTV transmissions
HF and theses waves pattern where not present.
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 12
Date: Tue, 6 May 2008 01:47:10 +0800
From: "Sion Chow Q. C. \(9W2QC\)" <9w2qc(AT)9w2qc.net>
Subject: [amsat-bb] Cute-1.7+APD and Compass-1 over West Malaysia
To: "'COMPASS-1 CubeSat'" <compass1cubesat(AT)googlemail.com>,
<cute1.7_receive(AT)lss.mes.titech.ac.jp>, "'seeds message'"
<seeds_message(AT)forth.aero.cst.nihon-u.ac.jp>
Cc: 'ybgo' <ybgo(AT)yahoo.com>, amsat-bb(AT)amsat.org
Message-ID: <002201c8aed8$124af390$36e0dab0$(AT)net>
Content-Type: text/plain; charset="us-ascii"
Dear All,
Cute-1.7+APD and Compass-1 over West Malaysia.
Time: 2305 Local or 1505 UTC
Max Elevation: 33 degrees
Tracking: Object C
http://www.9w2qc.net/amsatbb/cute05may2305.mp3
To the SEEDS team, I attempted to listen to the earlier pass, and SEEDS was
in FM digi talker mode. Did not listen to SEEDS during the above pass
though. Since the message is the same, I decided to set the station to
record in USB mode unattended in case CW telemetry comes on instead.
This will be my last report to the AMSAT-BB to reduce bandwidth. All future
reports will only be sent directly to the respective satellite teams except
for some interesting findings.
73,
Sion Chow Q. C.,
9W2QC.
------------------------------
Message: 13
Date: Mon, 5 May 2008 20:13:07 +0200
From: "Wouter Jan Ubbels" <wjubbels(AT)gmail.com>
Subject: [amsat-bb] Re: Creating Artworks based on Delfi-C3... or ?
To: i8cvs <domenico.i8cvs(AT)tin.it>
Cc: "Henk, PA3GUO" <hamoen(AT)iae.nl>, AMSAT-BB <amsat-bb(AT)amsat.org>,
pa3guo(AT)amsat.org
Message-ID:
<af4c9b1b0805051113q79fa74bbh808f4d731eb60afb(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Hi Domenico, Henk & all,
Domenico, you are totally right, that is indeed what is happening. When
looking boresight, it is true CP, but looking more to the side it progresses
slowly to more and more elliptical to almost truely linear when looking 90
degrees from boresight. (I liked your comparison to a phonograph record!)
Henk, PA3GUO, your plots are more than just art, besides looking nice they
are truely useful, and they support our observations that Delfi-C3 is slowly
tumbling around one of the 2 short axis. Any tumble around the long axis
would be hard to observe from polarization data, since the antenna of the
s/c appears to be very nicely circular with good axial ratio figures. During
the development, we have performed measurements on a 1:1 scale antenna model
and these measurements showed the same.
Delfi-C3's antenna is indeed, like Domenico said, comparable to two dipoles
fed 90 degrees out of phase. Actually, they are 4 monopole antennas which
are fed with 0, 90, 180, 270 degrees from a phasing network, which also
connects the other transceiver to the same antenna system. (Side effect of
this is that switching to the other transceiver reverses the circular
polarity sense).
Oh, speaking about art, did you know that Delfi-C3 actually carries a work
of art into space?
See
http://www.delfic3.nl/index.php?option=com_content&task=view&id=78&Itemid=118
73
Wouter Jan Ubbels PE4WJ
On Mon, May 5, 2008 at 6:37 PM, i8cvs <domenico.i8cvs(AT)tin.it> wrote:
> ----- Original Message -----
> From: "Henk, PA3GUO" <hamoen(AT)iae.nl>
> To: <amsat-bb(AT)amsat.org>
> Cc: <pa3guo(AT)amsat.org>
> Sent: Monday, May 05, 2008 6:42 AM
> Subject: [amsat-bb] Creating Artworks based on Delfi-C3... or ?
>
> > Dear all,
> >
> > Previous days it was observed already, then in periods of maximum signal
> > strengths on LHCP, there is a minimum on RCHP (and visa versa).
> > Triggered by that I wanted to try something else: simulations reception
> > of the two antennas of my 'X' antenna (2x6 elements DK7ZB), and plot the
> > signal strengths over time.
> >
> > Most likely this can be considered as a totally useless experiment, but
> > I wanted to do this for once (could have taken another satellite as
> well).
> > Both antennas are only 6 cm distance from eachother, which is
> compensated
> > by a bit of extra coax cable. The two cables enter the shack.
> >
> > One cable has been connected to an FT817. Other cable was connected to
> > an TS2000. Using this set-up I did a simulatious reception of Delfi C3,
> > and plotted the received signals above eachother:
> > Result: Maximum on one antenna is minimum on the other, and visa versa.
> >
> > Have a look yourself at the graph:
> >
>
> http://home.vianetworks.nl/users/hamoen/pa3guo/dc3_04may08_2000utc_pa3guo_po
> larization_145.930.jpg
> >
> > Conclusion of PA3GUO: fun to do, but I have no clue what this tells us
> :-)
> > Conclusion of PE1ITR: it's beautiful, but one does not know what one can
> do with it... it's ART ! :-)
> >
> > ... still:
> > - if Delfi C3 has circular polarization, shouldn't both signals have
> been
> the same ?
> > - how does this relate to the LCHP/RCHP opposite maximums (see text
> above)
> ?
> >
> > Looking forward for your thoughts !
> >
> > 73, Henk, PA3GUO
> > http://www.qsl.net/pa3guo
> >
> Hi Henk, PA3GUO
>
> Delfi-C3 is transmitting circularly polarized no matter if RHCP or LHCP
> because it depend on which side the satellite look at your antennas and
> more on this later.
> As you stated you are receiving with an "X" antenna made of two linearly
> polarized antennas one is oriented at 45? "/" and the other one at 135?
> "\"
>
> The point here is that the transmitting antenna of Delfi-C3 is not looking
> straight boreside at any time to your receiving antennas because the
> satellite is slowly tumbling.
>
> If we assume that at a certain time the transmitting and receiving
> antennas
> have been randomly looking straight at each other (coaxial) then a
> circularly polarized wave will appear circularly polarized with the same
> amplitude into your "X" antennas.
>
> If the antennas are not looking directly at each other because there is a
> continuously variable squint angle with the satellite tumbling then a
> circularly polarized wave will appear elliptical to your linearly
> receiving
> "X" antennas.
>
> This effect is easily visualized if you look at a phonograph record ;
> looking directly onto the playing surface , it appears round .As the
> record
> (the satellite CP antenna) is rotated toward an edgewiseview ,it appears
> more and more elliptical until, when you are looking directly at the edge
> of the record, it appears as a straight line.
>
> This effect can be applied here and when your two crossed linearly
> polarized
> "X" antennas are looking directly into a circularly polarized antenna, the
> X components are equal:As one moves around to the edge of the antennas
> (satellite tumbling) one of the X linear components increases while the
> other X component decreases or approaches to zero.
>
> If the linear component that appears as a straight line is oriented
> exactly
> at 45? "/" with respect to your "X" antennas then the signal received by
> the
> 45? "/" antenna is maximum while the signal received by the 135? "\"
> antenna is minimum or zero.
>
> Your question 1 :
> if Delfi C3 has circular polarization, shouldn't both signals have been
> the
> same ?
>
> My answer 1 :
> They are the same strenght only when Delfi C3 and your "X" antennas are
> looking straight at each other.
>
> Your question 2 :
> how does this relate to the LCHP/RCHP opposite maximums (see text above )
> ?
>
> My answer 2 :
> If you are receiving a LHCP or RHCP wave with an "X" linearly polarized
> antenna the signals is the same but if you receive with a CP antenna the
> effect changes.
> The antenna of Delfi C3 is made with 2 crossed elements located in the
> same
> plane.
> To generate circular polarization one element must be feed with a 90?
> phase
> difference.
> Been the crossed elements in the same plane without any reflector the
> antenna radiates RHCP in one axial direction and LHCP in the other
> direction.
> If you receive with a circularly polarized antenna it happens that
> depending
> on wich face the satellite is looking to your "X" antennas you can receive
> a
> RHCP or a LHCP wave and this is why a polarization switcher is necessary.
>
> I have extracted this basic concept from " The Advantages of Circular
> Polarization for Amateur Satellite Ground Stations" by John J. Nagle, K4KJ
> publisched into the "1975 ARRL Technical Symposium" page 80-87 of text
> with 25 pages for drawings and pictures.
>
> 73" de
>
> i8CVS Domenico
>
>
>
>
> _______________________________________________
> 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!
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>
------------------------------
Message: 14
Date: Mon, 5 May 2008 13:21:50 -0500 (GMT-05:00)
From: George Henry <ka3hsw(AT)earthlink.net>
Subject: [amsat-bb] Re: AO-16 currently silent and resting 11:15UTC
5May2008
To: "Mark L. Hammond" <n8mh(AT)embarqmail.com>, amsat-bb(AT)amsat.org
Message-ID:
<27698442.1210011710166.JavaMail.root(AT)elwamui-
lapwing.atl.sa.earthlink.net>
Content-Type: text/plain; charset=UTF-8
Any chance that it will be available for use for the Scout-O-Rama Special
Event station (K9BSA) this Saturday, 5/10?
George, KA3HSW
-----Original Message-----
>From: "Mark L. Hammond" <n8mh(AT)embarqmail.com>
>Sent: May 5, 2008 6:33 AM
>To: amsat-bb(AT)amsat.org
>Subject: [amsat-bb] AO-16 currently silent and resting 11:15UTC 5May2008
>
>Hello all,
>
>The weekend presented a chance to gather some telemetry on AO-16. The
telemetry looks nominal. Recently, the satellite seems to go silent on a
nearly daily basis. Increasing eclipse periods remain a likely explanation,
but we remain open to other explanations at this point.
>
>To this end, I have turned AO-16 OFF for a few days to rest and ensure that
its batteries will be given a chance to become fully charged. Following its
several day rest period, we'll try to conduct more tests to better determine
what type of operations that AO-16 is currently able to support.
>
>Please do not transmit to AO-16 until further notice.
>
>73 on behalf of the command team (and Happy Cinco de Mayo!),
>
>Mark L. Hammond [N8MH]
------------------------------
_______________________________________________
Sent via amsat-bb(AT)amsat.org. 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 225
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