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CX2SA > SATDIG 28.11.08 01:23l 1121 Lines 37124 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: AO-51 reload (Tim Tapio)
2. Re: Help for Humber College Students with ISS Contact (Alan)
3. Re: Help for Humber College Students with ISS Contact (Alan)
4. Re: BBsat Call for ideas (Bob Bruninga )
5. LVB tracker ( Dirgantara R YF0EEE)
6. AMSAT Orbit Magazines 1-4 (Phil Karn Jr, KA9Q)
7. Re: AMSAT Orbit Magazines 1-4 (Glen Zook)
8. [Fwd: Re: AMSAT Orbit Magazines 1-4] (Dee)
9. whole pass AO-51 tlm RX (nader omer)
10. Re: AO-51 mode L/U (Greg D.)
----------------------------------------------------------------------
Message: 1
Date: Wed, 26 Nov 2008 21:15:13 -0500
From: "Tim Tapio" <tim@xxxxxxxx.xxx>
Subject: [amsat-bb] Re: AO-51 reload
To: "'Andrew Glasbrenner'" <glasbrenner@xxxxxxxxxx.xxx>,
<amsat-bb@xxxxx.xxx>
Cc: WA4SXM@xxxxx.xxx
Message-ID: <002601c95035$fbead610$f3c08230$@xxx>
Content-Type: text/plain; charset="us-ascii"
How does one say "Thanks" to such great volunteers?
Tim T. K4SHF
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Andrew Glasbrenner
Sent: Wednesday, November 26, 2008 7:39 PM
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] AO-51 reload
It looks like we'll be reloading AO-51 for Thanksgiving. Gould started the
process this evening, and I expected it'll be Saturday or later before
it's
back open for general use.
73, Drew KO4MA
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. 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: 2
Date: Wed, 26 Nov 2008 20:16:27 -0600
From: "Alan" <ve4yz@xxx.xxx>
Subject: [amsat-bb] Re: Help for Humber College Students with ISS
Contact
To: "'Roger Kolakowski'" <rogerkola@xxx.xxx>, <AJ9N@xxx.xxx>,
<gordonjcp@xxxx.xxx>, <amsat-bb@xxxxx.xxx>, <paul_je@xxxxxxx.xxx>
Message-ID: <5C0D06C96B014D278A425293A13B2613@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
With all due respect to describing LHCP and RHCP which gives me a brain
crap... Here is a visualization of polarization.
http://sv1bsx.50webs.com/antenna-pol/polarization.html
... Alan
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Roger Kolakowski
Sent: November 26, 2008 5:38 PM
To: AJ9N@xxx.xxxx gordonjcp@xxxx.xxxx amsat-bb@xxxxx.xxxx
paul_je@xxxxxxx.xxx
Subject: [amsat-bb] Re: Help for Humber College Students with ISS Contact
Nice explanation...Thank you!
Roger
WA1KAT
----- Original Message -----
From: <AJ9N@xxx.xxx>
To: <gordonjcp@xxxx.xxx>; <amsat-bb@xxxxx.xxx>; <paul_je@xxxxxxx.xxx>
Sent: Wednesday, November 26, 2008 11:04 AM
Subject: [amsat-bb] Re: Help for Humber College Students with ISS Contact
> Hi all,
>
> Let me clear up a little bit of what ARISS wants for a school ground
> station. What you do for your own home contact is your business but
> here
is what we
> want for an ARISS school contact:
>
> 1. We require two complete radio stations, each one 75 watt class or
better
> (we actually prefer over 100). RF amps are OK. The radios should
> have
the
> ability to go in frequency steps smaller than 5kHz so that the
> Doppler
shift
> can be corrected (at 2 meters it goes about +/-3.5 kHz).
> 2. The primary radio is to have a circular polarized beam with
> azimuth
and
> elevation control rotors. We prefer computer control of the rotors.
> 3. The backup radio is to have a vertical and/or eggbeater style
antennas.
>
> Now for a short explanation of why for each:
>
> 1. The need for two complete radios is so that if one radio fails for
any
> reason, the school contact can carry on (it is recommended each radio
> be
on
> its own 120VAC circuit and UPS if possible). The reason for the 75
> watt
class
> is that we want to have as much signal to reach the ISS as possible.
> The
ISS
> is actually pretty noisy and the radio footprint is very big and it
> picks
up
> all sorts of interference. So it helps to have as much signal get to
> the astronaut. Throw in the fact that the ISS superstructure is so
> big now
that we
> have had schools have the signal dropout to almost nothing and you
> can
see
> that every little bit helps.
>
> 2. The circular polarized beam helps because the signal to and from
> the
ISS
> can be bouncing off of the superstructure itself and in some cases the
> surrounding ground terrain. As I mentioned above, we have had some
schools where
> the signal dropped out almost to zero. Luckily the signal (sometimes
about a
> minute later) came back up as the ISS changed its orbital position
relative
> to the ground station and thus some of the blockage was reduced. I have
done
> 4 school contacts as control op and I use 5x2 LHCP and 10x2 RHCP
> circular polarized beams with an antenna switch. Most of the ARISS
> telebridge
stations
> are using something similar. The ISS antennas are basically vertical
> antennas but the signal can be deflected all over the place because
> of
the
> superstructure. I tend to run my contact on the RHCP beam (but I am
ready to
> switch) but we at ARISS have had some reports where the signal did
> come
up a bit
> when using LHCP. Those who are really into satellite work know that
> the
RF
> pattern does change during a contact so it makes sense to be able to
switch
> polarity. And don't forget the ISS radio is running maybe 25 watts
> (or
maybe 5
> depending on the radio used) and can not do any Doppler correction.
>
> 3. The backup radio is to have a non-directional antenna so that in
> case
of
> rotor or computer failure, the contact can carry on although it will
> be
with
> a shortened contact time and the quality may suffer. I have an
> antenna switch to switch between the 2 antennas during a pass as the
> RF pattern
between
> the 2 antennas is completely different.
>
> The biggest reason for doing what some may think is overkill is this.
The
> hams involved with a school contact are just the messengers. The
> school
kids,
> teachers, and parents are the ones we have to satisfy and they don't
> understand this ham radio business. They do understand good audio
> and no
screw ups
> on the part of the ham crew. I always tell the schools that I mentor
> to
plan
> on 600 to 800 people-hours for 10 minutes of contact time. They
> usually think I am nuts until they do the contact and they often tell
> me that my estimate was too low. Think of a school contact as your
> worst case Field
Day; not
> so much because of the equipment issues but because of the 600 or so
> kids watching.
>
> Hope this helps a little.
>
> 73,
> Charlie Sufana AJ9N
> One of the ARISS mentors
>
>
>
> In a message dated 11/26/2008 4:15:52 A.M. Central Standard Time,
> gordonjcp@xxxx.xxx writes:
>
> Ken Owen wrote:
> <snip>
> > From: Paul Je [mailto:paul_je@xxxxxxx.xxxx
> > Sent: Monday, November 24, 2008 1:17 PM
> > To: Ken Owen
> > Subject: RE: ISS contact
> >
> > Say Ken, we've set up our primary station just fine, but I was
wondering if
> > I could ask for your advice. Well, you see, we've tested the
transceiver
> > that we have (the ICOM IC-V8000), and we can transmit and receive
> > just
fine
> > with it on our circular-polarized HyGain 2m antenna. Also, we did
> > a
VSWR
>
> What kind of antenna? Anything more than a 3-element Yagi will be
> more trouble than it's worth. Bear in mind that I've successfully
> sent and received APRS with the ISS using a homebrew vertical. The
> higher the gain of your Yagi, the more directional it is, and the
> more accurately it needs to be pointed. I find that a 3-element beam
> is okay for handheld use when working portable, and has more than
> enough gain to hit the amateur satellites with 5W from an HT.
>
> > test and our loss is minimal with the 75W transceiver that the ICOM
>
> 75W sounds a bit much, especially into a very directional antenna.
> You're trying to talk to the ISS, not etch your name on the side.
>
> > produces. Ok, so here's the problem. Even with all the proper
> > testing done, we still can't seem to pick up or hear the 166MHz
> > beacon that the
ISS
> > produces.
>
> Are you using a 166MHz aerial for this? Are you sure the beacon is
> even transmitting when you think it is? Your high gain Yagi might
> well be very very deaf outside its intended band. Try making a
> simple dipole or even a two-element beam for 166MHz. With two
> elements, it will have a more-or-less cardioid pattern, so you
> shouldn't really even need to steer it much ;-)
>
> > My classmates and I are a bit worried/stressed out. I mean, just
> > on
last
> > Friday, we did a test and someone drove at least 5km away from out
college
> > and heard us fine with the handheld radio he had. We had a signal
strength
> > of 3+ out of 5. He could've drove out even further, but we felt
> > that
we
> did
> > enough testing to know that any attenuation losses were very minimal.
>
> The ISS is pretty much the classic case of line-of-sight. There's
> nothing in the way, and it's only 200 miles away. There's nothing to
> stop the signal anywhere.
>
> > Well, do you know what the problem could be? Have you heard the
beacon?
> > What does it sound like? Maybe we should delay or advance the
> > rotor by
a
> > few seconds? We're using NOVA software, and it allows us to send our
> > transmission a few seconds ahead or behind.
>
> Use a wider beamwidth.
>
> > Ok, so we have a circular polarized HyGain antenna hooked up to our
Yaesu
> > G5500. Uhm, this might sound dumb but do you know whether we
> > should
be
> > right hand circular polarized or left hand circular polarized? Is
> > the
ISS
> > right hand or left hand on 144.490MHz?
>
> This I'm not sure about. I thought about building a circular
> polarised antenna for ISS and amateur satellite work, but it seemed
> more trouble than it was worth. If you've got the polarisation
> wrong, it will be incredibly deaf!
>
> > I'm trying to research this, but I'm having the hardest time to
> > find
this
> > information out. Oh, also, since our antenna is
> > circular-polarized,
does
> > the way we set our antenna have an effect on our transmission? I
> > know
this
> > sounds confusing, but let me explain:
> >
> > If you looked at our antenna from the front so that you could see
> > all
the
> > dipoles/elements both vertically and horizontally to your view,
> > well,
> should
> > they be perfectly aligned with one set horizontal and one vertical?
Both
> > the vertical and the horizontal are perfectly 90degrees to each
> > other, however, instead of being a perfect cross to your view, the
> > elements
are
> > more like an "X" to your point of view (even though both are
> > perfectly 90degrees to each other).
>
> That shouldn't make much of a difference. Imagine the signal
> arriving like a big corkscrew - the key to the circular polarisation
> is that the signal arrives at one set of elements and then a quarter
> wavelength later arrives at the second. Now, let's imagine we've
> made our circular-polarised aerial by putting two dipoles on a boom, 1/4
> wavelength apart, and connected them by two equal-length lines. The
> vertical one is at the "front" of the boom and the horizontal one is
> to the "back", and the up and left elements of the dipoles are "hot".
>
> Let's pause reality just as a "vertical" peak hits the vertical dipole.
> That dipole now has some signal. Using the single-Planck-time
> advance button on our Worldivo (it's like a Tivo for the fundamental
> nature of the Universe), we'll step through - tick, tick, tick, tick
> - until a quarter wavelength has passed. Now the vertical peak is
> somewhere above the centre of the horizontal dipole - it's picking up
> no signal - and there's a horizontal peak about the centre of the
> vertical dipole - no signal there either.
>
> Step forwards another quarter wave, and there's a vertical dip at the
> cold end of the vertical antenna, and the horizontal peak we just saw
> came in is at the hot end on the horizontal antenna. We now have a
> negative signal on the cold side of the antenna connection (remember,
> both dipoles are effectively in parallel) and a positive signal on
> the hot side of the antenna connection - loads of signal!
>
> If we reversed the direction of the corkscrew, or reversed the phase
> of
> *one* of the dipoles, then the two signals would cancel out almost
> completely. You can have two signals transmitted in left and right
> circular polarisation on the same frequency, and have *phenomenal*
> rejection between the two.
>
> I should point out that there's quite a lot in that explanation
> that's not entirely true, or at least terribly inaccurate. It's
> still a useful model for getting your head around what seems at first
> to be a very confusing polarisation mode.
>
> HTH,
> Gordon
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
>
> **************Life should be easier. So should your homepage. Try the
> NEW AOL.com.
>
(http://www.aol.com/?optin=new-dp&icid=aolcom40vanity&ncid=emlcntaolcom0000
0
002)
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. 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: 3
Date: Wed, 26 Nov 2008 20:29:52 -0600
From: "Alan" <ve4yz@xxx.xxx>
Subject: [amsat-bb] Re: Help for Humber College Students with ISS
Contact
To: <amsat-bb@xxxxx.xxx>, <paul_je@xxxxxxx.xxx>
Message-ID: <74947E53F52B401E88A6DDDF6DB21410@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Sorry for the spam but I neglected to include the URL to a great open
source
application ENAMIN
http://www.enzim.hu/~szia/emanim/emanim.htm used to create these graphic
simulations of polarization
You don't have to download and run it... Several samples are included on
the
site such as
http://www.enzim.hu/~szia/cddemo/edemo0.htm
... Alan
-----Original Message-----
From: Alan [mailto:ve4yz@xxx.xxxx
Sent: November 26, 2008 8:16 PM
To: 'Roger Kolakowski'; 'AJ9N@xxx.xxxxx 'gordonjcp@xxxx.xxxxx
'amsat-bb@xxxxx.xxxxx 'paul_je@xxxxxxx.xxxx
Subject: RE: [amsat-bb] Re: Help for Humber College Students with ISS
Contact
With all due respect to describing LHCP and RHCP which gives me a brain
crap... Here is a visualization of polarization.
http://sv1bsx.50webs.com/antenna-pol/polarization.html
... Alan
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Roger Kolakowski
Sent: November 26, 2008 5:38 PM
To: AJ9N@xxx.xxxx gordonjcp@xxxx.xxxx amsat-bb@xxxxx.xxxx
paul_je@xxxxxxx.xxx
Subject: [amsat-bb] Re: Help for Humber College Students with ISS Contact
Nice explanation...Thank you!
Roger
WA1KAT
----- Original Message -----
From: <AJ9N@xxx.xxx>
To: <gordonjcp@xxxx.xxx>; <amsat-bb@xxxxx.xxx>; <paul_je@xxxxxxx.xxx>
Sent: Wednesday, November 26, 2008 11:04 AM
Subject: [amsat-bb] Re: Help for Humber College Students with ISS Contact
> Hi all,
>
> Let me clear up a little bit of what ARISS wants for a school ground
> station. What you do for your own home contact is your business but
> here
is what we
> want for an ARISS school contact:
>
> 1. We require two complete radio stations, each one 75 watt class or
better
> (we actually prefer over 100). RF amps are OK. The radios should
> have
the
> ability to go in frequency steps smaller than 5kHz so that the
> Doppler
shift
> can be corrected (at 2 meters it goes about +/-3.5 kHz).
> 2. The primary radio is to have a circular polarized beam with
> azimuth
and
> elevation control rotors. We prefer computer control of the rotors.
> 3. The backup radio is to have a vertical and/or eggbeater style
antennas.
>
> Now for a short explanation of why for each:
>
> 1. The need for two complete radios is so that if one radio fails for
any
> reason, the school contact can carry on (it is recommended each radio
> be
on
> its own 120VAC circuit and UPS if possible). The reason for the 75
> watt
class
> is that we want to have as much signal to reach the ISS as possible.
> The
ISS
> is actually pretty noisy and the radio footprint is very big and it
> picks
up
> all sorts of interference. So it helps to have as much signal get to
> the astronaut. Throw in the fact that the ISS superstructure is so
> big now
that we
> have had schools have the signal dropout to almost nothing and you
> can
see
> that every little bit helps.
>
> 2. The circular polarized beam helps because the signal to and from
> the
ISS
> can be bouncing off of the superstructure itself and in some cases the
> surrounding ground terrain. As I mentioned above, we have had some
schools where
> the signal dropped out almost to zero. Luckily the signal (sometimes
about a
> minute later) came back up as the ISS changed its orbital position
relative
> to the ground station and thus some of the blockage was reduced. I have
done
> 4 school contacts as control op and I use 5x2 LHCP and 10x2 RHCP
> circular polarized beams with an antenna switch. Most of the ARISS
> telebridge
stations
> are using something similar. The ISS antennas are basically vertical
> antennas but the signal can be deflected all over the place because
> of
the
> superstructure. I tend to run my contact on the RHCP beam (but I am
ready to
> switch) but we at ARISS have had some reports where the signal did
> come
up a bit
> when using LHCP. Those who are really into satellite work know that
> the
RF
> pattern does change during a contact so it makes sense to be able to
switch
> polarity. And don't forget the ISS radio is running maybe 25 watts
> (or
maybe 5
> depending on the radio used) and can not do any Doppler correction.
>
> 3. The backup radio is to have a non-directional antenna so that in
> case
of
> rotor or computer failure, the contact can carry on although it will
> be
with
> a shortened contact time and the quality may suffer. I have an
> antenna switch to switch between the 2 antennas during a pass as the
> RF pattern
between
> the 2 antennas is completely different.
>
> The biggest reason for doing what some may think is overkill is this.
The
> hams involved with a school contact are just the messengers. The
> school
kids,
> teachers, and parents are the ones we have to satisfy and they don't
> understand this ham radio business. They do understand good audio and
> no
screw ups
> on the part of the ham crew. I always tell the schools that I mentor
> to
plan
> on 600 to 800 people-hours for 10 minutes of contact time. They
> usually think I am nuts until they do the contact and they often tell
> me that my estimate was too low. Think of a school contact as your
> worst case Field
Day; not
> so much because of the equipment issues but because of the 600 or so
> kids watching.
>
> Hope this helps a little.
>
> 73,
> Charlie Sufana AJ9N
> One of the ARISS mentors
>
>
>
> In a message dated 11/26/2008 4:15:52 A.M. Central Standard Time,
> gordonjcp@xxxx.xxx writes:
>
> Ken Owen wrote:
> <snip>
> > From: Paul Je [mailto:paul_je@xxxxxxx.xxxx
> > Sent: Monday, November 24, 2008 1:17 PM
> > To: Ken Owen
> > Subject: RE: ISS contact
> >
> > Say Ken, we've set up our primary station just fine, but I was
wondering if
> > I could ask for your advice. Well, you see, we've tested the
transceiver
> > that we have (the ICOM IC-V8000), and we can transmit and receive
> > just
fine
> > with it on our circular-polarized HyGain 2m antenna. Also, we did
> > a
VSWR
>
> What kind of antenna? Anything more than a 3-element Yagi will be
> more trouble than it's worth. Bear in mind that I've successfully
> sent and received APRS with the ISS using a homebrew vertical. The
> higher the gain of your Yagi, the more directional it is, and the
> more accurately it needs to be pointed. I find that a 3-element beam
> is okay for handheld use when working portable, and has more than
> enough gain to hit the amateur satellites with 5W from an HT.
>
> > test and our loss is minimal with the 75W transceiver that the ICOM
>
> 75W sounds a bit much, especially into a very directional antenna.
> You're trying to talk to the ISS, not etch your name on the side.
>
> > produces. Ok, so here's the problem. Even with all the proper
> > testing done, we still can't seem to pick up or hear the 166MHz
> > beacon that the
ISS
> > produces.
>
> Are you using a 166MHz aerial for this? Are you sure the beacon is
> even transmitting when you think it is? Your high gain Yagi might
> well be very very deaf outside its intended band. Try making a
> simple dipole or even a two-element beam for 166MHz. With two
> elements, it will have a more-or-less cardioid pattern, so you
> shouldn't really even need to steer it much ;-)
>
> > My classmates and I are a bit worried/stressed out. I mean, just
> > on
last
> > Friday, we did a test and someone drove at least 5km away from out
college
> > and heard us fine with the handheld radio he had. We had a signal
strength
> > of 3+ out of 5. He could've drove out even further, but we felt
> > that
we
> did
> > enough testing to know that any attenuation losses were very minimal.
>
> The ISS is pretty much the classic case of line-of-sight. There's
> nothing in the way, and it's only 200 miles away. There's nothing to
> stop the signal anywhere.
>
> > Well, do you know what the problem could be? Have you heard the
beacon?
> > What does it sound like? Maybe we should delay or advance the
> > rotor by
a
> > few seconds? We're using NOVA software, and it allows us to send our
> > transmission a few seconds ahead or behind.
>
> Use a wider beamwidth.
>
> > Ok, so we have a circular polarized HyGain antenna hooked up to our
Yaesu
> > G5500. Uhm, this might sound dumb but do you know whether we
> > should
be
> > right hand circular polarized or left hand circular polarized? Is
> > the
ISS
> > right hand or left hand on 144.490MHz?
>
> This I'm not sure about. I thought about building a circular
> polarised antenna for ISS and amateur satellite work, but it seemed
> more trouble than it was worth. If you've got the polarisation
> wrong, it will be incredibly deaf!
>
> > I'm trying to research this, but I'm having the hardest time to
> > find
this
> > information out. Oh, also, since our antenna is
> > circular-polarized,
does
> > the way we set our antenna have an effect on our transmission? I
> > know
this
> > sounds confusing, but let me explain:
> >
> > If you looked at our antenna from the front so that you could see
> > all
the
> > dipoles/elements both vertically and horizontally to your view,
> > well,
> should
> > they be perfectly aligned with one set horizontal and one vertical?
Both
> > the vertical and the horizontal are perfectly 90degrees to each
> > other, however, instead of being a perfect cross to your view, the
> > elements
are
> > more like an "X" to your point of view (even though both are
> > perfectly 90degrees to each other).
>
> That shouldn't make much of a difference. Imagine the signal
> arriving like a big corkscrew - the key to the circular polarisation
> is that the signal arrives at one set of elements and then a quarter
> wavelength later arrives at the second. Now, let's imagine we've
> made our circular-polarised aerial by putting two dipoles on a boom, 1/4
> wavelength apart, and connected them by two equal-length lines. The
> vertical one is at the "front" of the boom and the horizontal one is
> to the "back", and the up and left elements of the dipoles are "hot".
>
> Let's pause reality just as a "vertical" peak hits the vertical dipole.
> That dipole now has some signal. Using the single-Planck-time
> advance button on our Worldivo (it's like a Tivo for the fundamental
> nature of the Universe), we'll step through - tick, tick, tick, tick
> - until a quarter wavelength has passed. Now the vertical peak is
> somewhere above the centre of the horizontal dipole - it's picking up
> no signal - and there's a horizontal peak about the centre of the
> vertical dipole - no signal there either.
>
> Step forwards another quarter wave, and there's a vertical dip at the
> cold end of the vertical antenna, and the horizontal peak we just saw
> came in is at the hot end on the horizontal antenna. We now have a
> negative signal on the cold side of the antenna connection (remember,
> both dipoles are effectively in parallel) and a positive signal on
> the hot side of the antenna connection - loads of signal!
>
> If we reversed the direction of the corkscrew, or reversed the phase
> of
> *one* of the dipoles, then the two signals would cancel out almost
> completely. You can have two signals transmitted in left and right
> circular polarisation on the same frequency, and have *phenomenal*
> rejection between the two.
>
> I should point out that there's quite a lot in that explanation
> that's not entirely true, or at least terribly inaccurate. It's
> still a useful model for getting your head around what seems at first
> to be a very confusing polarisation mode.
>
> HTH,
> Gordon
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
>
>
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_______________________________________________
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------------------------------
Message: 4
Date: Wed, 26 Nov 2008 22:18:50 -0500 (EST)
From: "Bob Bruninga " <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: BBsat Call for ideas
To: Bruce Robertson <ve9qrp@xxxxx.xxx>, "Greg D."
<ko6th_greg@xxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <20081126221850.AIG64598@xxx.xxxxxxx.xxxx.xxx>
Content-Type: text/plain; charset=us-ascii
> One idea that hasn't been floated yet,
> is a 10m or 15m transmitter aboard bbSat.
We looked at that, but the problem is the order of magnitude fewer hams
that
have SSB transceivers. We went with a 10m uplink to an FM downlink so
that
any technician with nothing but an HT could hear it.
But then, you have gained nothing over the typical FM satellite b ecause
of
single-use. So that is why we went with PSK-31 on the 10m uplink so that
the
single 2m FM downlink would have as many as 30 ussers simultaneously (all
sharing the 10 m PSK-31 3 KHz wide uplink.
> I therefore think a transponder that
> downlinked on these bands would be
> likely to 'broaden our base',
> I recognize that transmitting on
> such a long wavelength from a 10cm
> cube represents a technical challenge
Yes, the 4 foot whip deployment on our RAFT cubesat is what failed, not
due to
the antenna deployment but due to an ejection anomoly that spun the
spacecraft
out of contorl (80 RPM) from which the 4' whip antenna deployment could
not
work.
Receiving 10 meters on a terribly small and inefficient antenna is no big
deal, because users on the ground would be uplinking with 25 watts, and
being
on 10m is 14 dB better link too, so uplink on 10m is easy.
So that is my preference, 3 KHz of PSK uplink on 10 meters with a single
FM
downlink with up to 30 users at a time... full duples too!
We flew this on PCSAT2 and on RAFT (though both had other problems leading
to
a lack of any meaningful success).
see:
www.ew.usna.edu/~bruninga/pcsat2.html
www.ew.usna.eud/~bruninga/raft.html
bob, Wb4APR
Bob, Wb4aPR
>challenge of mechanical engineering, not something that would run up
>against the limited power budget. I also vaguely have the impression
>that amplifiers, etc. are more efficient in the lower frequencies, so
>that might be a plus. (Not to mention reduced path loss.) Perhaps the
>effective power out would be so low that a directional antenna would
>be required on the ground. In which case, I'd say it was a no-go,
>since that would preclude too many of the new experimenters that we'd
>be hoping to snare on these bands.
>_______________________________________________
>Sent via AMSAT-BB@xxxxx.xxx. 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: 5
Date: Thu, 27 Nov 2008 14:25:51 +0700
From: " Dirgantara R YF0EEE" <enggi1401@xxxxx.xxx>
Subject: [amsat-bb] LVB tracker
To: <amsat-bb@xxxxx.xxx>
Message-ID: <00c601c95061$69f34450$1c3d3a72@xxxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi everyone
any body use LVB tracker use KR-500 and KR-400 rotator,
how about a performance and accuracy for elevasi and azimuth ?
73 de YF0EEE
------------------------------
Message: 6
Date: Thu, 27 Nov 2008 06:17:02 -0800
From: "Phil Karn Jr, KA9Q" <karn@xxxx.xxx>
Subject: [amsat-bb] AMSAT Orbit Magazines 1-4
To: amsat-bb@xxxxx.xxxx "Ralph Wallio, W0RPK" <W0RPK@xxxxxx.xxx>
Message-ID: <492EABDE.9060404@xxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Thanks to Ralph, W0RPK, the first four issues of AMSAT Orbit magazine
are scanned and online. ORBIT began publication shortly before the
ill-fated Phase III-A launch in 1980.
http://www.ka9q.net/newsletters.html
73, Phil
------------------------------
Message: 7
Date: Thu, 27 Nov 2008 07:35:08 -0800 (PST)
From: Glen Zook <gzook@xxxxx.xxx>
Subject: [amsat-bb] Re: AMSAT Orbit Magazines 1-4
To: amsat-bb@xxxxx.xxxx "Ralph Wallio, W0RPK" <W0RPK@xxxxxx.xxx>,
"Phil Karn Jr, KA9Q" <karn@xxxx.xxx>
Message-ID: <863463.66752.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Are you interested in the original bulletins? "Somewhere" I should have
all
of the original bulletins except for the very first. I have been a member
of
AMSAT since the first couple of months of its formation and, being a "pack
rat", I keep things like organization bulletins. It is just a matter of
locating them!
If I can find them, I can loan them to you for scanning. Of course I
would
like them back when you are through.
Glen, K9STH
AMSAT 239/LM 463
Website: http://k9sth.com
--- On Thu, 11/27/08, Phil Karn Jr, KA9Q <karn@xxxx.xxx> wrote:
From: Phil Karn Jr, KA9Q <karn@xxxx.xxx>
Thanks to Ralph, W0RPK, the first four issues of AMSAT Orbit magazine are
scanned and online. ORBIT began publication shortly before the ill-fated
Phase
III-A launch in 1980.
http://www.ka9q.net/newsletters.html
------------------------------
Message: 8
Date: Thu, 27 Nov 2008 11:29:09 -0500
From: Dee <morsesat@xxxxxxxxx.xxx>
Subject: [amsat-bb] [Fwd: Re: AMSAT Orbit Magazines 1-4]
To: AMSAT-BB@xxxxx.xxx
Message-ID: <492ECAD5.9040801@xxxxxxxxx.xxx>
Content-Type: text/plain; charset=us-ascii; format=flowed
All involved...
Thanks for the run down memory lane. I recognized most of you but I
would be torn to recognize some.
The organization needs to remember its "roots!'
73,
Dee,
NB2F
-------- Original Message --------
Subject: [amsat-bb] Re: AMSAT Orbit Magazines 1-4
Date: Thu, 27 Nov 2008 07:35:08 -0800 (PST)
From: Glen Zook <gzook@xxxxx.xxx>
Reply-To: gzook@xxxxx.xxx
To: amsat-bb@xxxxx.xxxx "Ralph Wallio, W0RPK" <W0RPK@xxxxxx.xxx>, "Phil
Karn Jr, KA9Q" <karn@xxxx.xxx>
Are you interested in the original bulletins? "Somewhere" I should have
all
of the original bulletins except for the very first. I have been a member
of
AMSAT since the first couple of months of its formation and, being a "pack
rat", I keep things like organization bulletins. It is just a matter of
locating them!
If I can find them, I can loan them to you for scanning. Of course I
would
like them back when you are through.
Glen, K9STH
AMSAT 239/LM 463
Website: http://k9sth.com
--- On Thu, 11/27/08, Phil Karn Jr, KA9Q <karn@xxxx.xxx> wrote:
From: Phil Karn Jr, KA9Q <karn@xxxx.xxx>
Thanks to Ralph, W0RPK, the first four issues of AMSAT Orbit magazine are
scanned and online. ORBIT began publication shortly before the ill-fated
Phase
III-A launch in 1980.
http://www.ka9q.net/newsletters.html
_______________________________________________
Sent via AMSAT-BB@xxxxx.xxx. 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: 9
Date: Thu, 27 Nov 2008 09:05:54 -0800 (PST)
From: nader omer <st2nh@xxxxx.xxx>
Subject: [amsat-bb] whole pass AO-51 tlm RX
To: amsat-bb@xxxxx.xxx
Message-ID: <553597.68497.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Hi all
?
A whole pass of AO-51 TLM RX at ?KK65GP
ORBIT # 23,195
16:24 16:38 UTC
signal was very strong from AOS?to ?LOS
using here only a?soundcard with AWGPE and UISS!
link to data?RX?in a?text format
http://www.st2nh.com/AO-51TLM27112008.zip
?
http://www.st2nh.com/satellites
73 Nader ,st2nh
www.st2nh.com
?
------------------------------
Message: 10
Date: Thu, 27 Nov 2008 11:32:10 -0800
From: "Greg D." <ko6th_greg@xxxxxxx.xxx>
Subject: [amsat-bb] Re: AO-51 mode L/U
To: <almetco@xxxxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <BLU133-W10CCB33FDF294A00754163A9050@xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Greg,
I've not tried L/U this week, but in the past I have been able to get in
with
10 watts from my ICOM 1271A to a homebrew 18 turn helix, with about 60' of
hardline and between 5 and 10' of RG-214 or similar at each end, between
the
rig and the antenna. I have no idea what power actually reaches the
antenna,
but, between the cable and all the connectors, I expect it's only a couple
of
watts at the most. Trees definitely are a factor (can't shoot through
them
very well), and I am on an Az/El rotor system so I can aim at the
satellite
pretty well.
As Drew notes, Doppler shift is really a factor on the upper bands.
You'll be
spinning the dial constantly. I use my satellite tracking program
(predict on
my Linux system) to tell me what frequency I should be on. I haven't
connected the rig to the computer yet, otherwise it would be automatically
controlled.
Good luck,
Greg KO6TH
> Date: Wed, 26 Nov 2008 02:37:35 +0000
> From: almetco@xxxxxxx.xxx
> To: amsat-bb@xxxxx.xxx
> Subject: [amsat-bb] AO-51 mode L/U
>
>
>
> I heard a few passes of AO-51 in L/U mode. Most stations came in strong. I
tried to get into the bird using about 8 watts out into a 23cm horizontal
yagi
on an elevation rotor. It was to no avail, though the bird was at 50
degree's
and higher. I am working on a CP antenna for mode L.
>
>
>
> Can those that worked this mode give me an idea of wattage, EIRP or antenna
for Mode L that you are using. I was sure 7-10 watts would do from the
Icom
910. However, it may have been the yagi and the lack of CP.
>
>
>
> Thanks
>
> Greg
>
> N3MVF
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. 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
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2008
------------------------------
_______________________________________________
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 615
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