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CX2SA > SATDIG 04.03.13 21:03l 575 Lines 16508 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.SAL.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: current operational amateur satellite list (jim@xxxxxx.xxx
2. STRaND1 polarity shift observation (Ken Swaggart)
3. Re: STRaND1 polarity shift observation (i8cvs)
4. Re: current operational amateur satellite list (Trevor .)
5. Re: STRaND1 polarity shift observation (Ken Swaggart)
6. Re: STRaND1 polarity shift observation (Ib Christoffersen)
7. Fw: Foxdelta ST-2 / LVB Tracker (Matty Cunningham)
8. Re: STRaND1 polarity shift observation (Alan)
----------------------------------------------------------------------
Message: 1
Date: Sun, 3 Mar 2013 18:04:16 -0500
From: jim@xxxxxx.xx
To: "Dave Webb KB1PVH" <kb1pvh@xxxxx.xxx>, "amsat-bb"
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: current operational amateur satellite list
Message-ID: <e10a0c9312fc2aef0e4530f98cd17a9e.squirrel@xxxx.xxxxxx.xx>
Content-Type: text/plain; charset="iso-8859-1"
Is AO-51 still operational??? Are their any FM sats that can be worked with
just a whip antenna ??? I have listened for SO-51 and can hear the becon?@
145.860 sometimes but no QSOs on 145.925 145.875.? Thanks
?
---------------------------- Original Message ----------------------------
Subject: Re: [amsat-bb] current operational amateur satellite list
From: "Dave Webb KB1PVH" <kb1pvh@xxxxx.xxx>
Date: Fri, February 22, 2013 5:06 pm
To: jim@xxxxxx.xx
--------------------------------------------------------------------------
> If you want voice satellites, here are your options.
>
> FM
> SO-50
> ISS, not voice but you can do packet
>
> SSB/CW
> VO-52
> AO-7
> FO-29
>
> That's it for now, but later this year there are a few more getting
> launched. Let me know if you need more info.
>
> Dave-KB1PVH
>
> Sent from my Verizon Wireless Droid RAZR
>
------------------------------
Message: 2
Date: Sun, 3 Mar 2013 20:10:39 -0800
From: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] STRaND1 polarity shift observation
Message-ID: <B81000F32068485C981308C5DA279900@xxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
During my last pass at 0332Z, max elevation 45 degrees out over the Pacific,
I noticed that STRaND1 was stronger when I selected LHCP while approaching
TCA. After TCA, RHCP was stronger while it was receding. I believe this
cubesat uses a whip, so not sure what is causing this.
Anyone have an idea why?
Tnx,
Ken, W7KKE
CN75xa
------------------------------
Message: 3
Date: Mon, 4 Mar 2013 09:42:27 +0100
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>, "Amsat - BBs"
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: STRaND1 polarity shift observation
Message-ID: <002f01ce18b4$34dcab60$0401a8c0@xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Ken, W7KKE
The answere to your question is clearly described into the zipped article
"Circular Polarization" by K4KJ, 5 MB long that I have sent to you in
a separate email.
73" de
i8CVS Domenico
----- Original Message -----
From: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Monday, March 04, 2013 5:10 AM
Subject: [amsat-bb] STRaND1 polarity shift observation
> During my last pass at 0332Z, max elevation 45 degrees out over the
Pacific,
> I noticed that STRaND1 was stronger when I selected LHCP while approaching
> TCA. After TCA, RHCP was stronger while it was receding. I believe this
> cubesat uses a whip, so not sure what is causing this.
>
> Anyone have an idea why?
>
> Tnx,
> Ken, W7KKE
> CN75xa
>
>
> _______________________________________________
> 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: 4
Date: Mon, 4 Mar 2013 13:20:33 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
To: Dave Webb KB1PVH <kb1pvh@xxxxx.xxx>, amsat-bb
<amsat-bb@xxxxx.xxx>, jim@xxxxxx.xx
Subject: [amsat-bb] Re: current operational amateur satellite list
Message-ID:
<1362403233.30021.YahooMailClassic@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Hi Jim,
There's a great list of active satellites at
http://www.dk3wn.info/p/?s=active+satellites&x=0&y=0
SO-50 is the only FM sat active.
73 Trevor M5AKA
--- On Sun, 3/3/13, jim@xxxxxx.xx <jim@xxxxxx.xx> wrote:
> From: jim@xxxxxx.xx <jim@xxxxxx.xx>
> Subject: [amsat-bb] Re: current operational amateur satellite list
> To: "Dave Webb KB1PVH" <kb1pvh@xxxxx.xxx>, "amsat-bb" <amsat-bb@xxxxx.xxx>
> Date: Sunday, 3 March, 2013, 23:04
>
>
>
> Is AO-51 still operational??? Are their any FM sats that
> can be worked with just a whip antenna ??? I have listened
> for SO-51 and can hear the becon?@ 145.860 sometimes but no
> QSOs on 145.925 145.875.? Thanks
> ?
> ---------------------------- Original Message
> ----------------------------
>
> Subject: Re: [amsat-bb] current operational amateur
> satellite list
>
> From: "Dave Webb KB1PVH" <kb1pvh@xxxxx.xxx>
>
> Date: Fri, February 22, 2013 5:06 pm
>
> To: jim@xxxxxx.xx
>
> --------------------------------------------------------------------------
>
>
>
> > If you want voice satellites, here are your options.
>
> >
>
> > FM
>
> > SO-50
>
> > ISS, not voice but you can do packet
>
> >
>
> > SSB/CW
>
> > VO-52
>
> > AO-7
>
> > FO-29
>
> >
>
> > That's it for now, but later this year there are a few
> more getting
>
> > launched. Let me know if you need more info.
>
> >
>
> > Dave-KB1PVH
>
> >
>
> > Sent from my Verizon Wireless Droid RAZR
>
> >
> _______________________________________________
> 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: 5
Date: Mon, 4 Mar 2013 08:02:49 -0800
From: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>
To: "i8cvs" <domenico.i8cvs@xxx.xx>, "Amsat - BBs"
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: STRaND1 polarity shift observation
Message-ID: <627AD7A23996452DB9A538EA601A9EAF@xxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Domenico,
Thanks for sending the K4KJ article.
However my question was why does STRaND1, which only has a whip antenna,
sometimes appear to exhibit circular polarity characteristics? I would
expect a whip antenna transmitting from space to have the same signal
strength on the ground using either RH or LH polarity on my receiving
antenna.
73,
Ken, W7KKE
-----Original Message-----
From: i8cvs
Sent: Monday, March 04, 2013 00:42
To: Ken Swaggart ; Amsat - BBs
Subject: Re: [amsat-bb] STRaND1 polarity shift observation
Hi Ken, W7KKE
The answere to your question is clearly described into the zipped article
"Circular Polarization" by K4KJ, 5 MB long that I have sent to you in
a separate email.
73" de
i8CVS Domenico
----- Original Message -----
From: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Monday, March 04, 2013 5:10 AM
Subject: [amsat-bb] STRaND1 polarity shift observation
> During my last pass at 0332Z, max elevation 45 degrees out over the
Pacific,
> I noticed that STRaND1 was stronger when I selected LHCP while approaching
> TCA. After TCA, RHCP was stronger while it was receding. I believe this
> cubesat uses a whip, so not sure what is causing this.
>
> Anyone have an idea why?
>
> Tnx,
> Ken, W7KKE
> CN75xa
>
>
> _______________________________________________
> 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: 6
Date: Mon, 4 Mar 2013 17:51:23 +0100
From: "Ib Christoffersen" <oz1my@xxxxxx.xx>
To: "'Ken Swaggart'" <k.swaggart@xxxxxxx.xxx>, "'i8cvs'"
<domenico.i8cvs@xxx.xx>, "'Amsat - BBs'" <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: STRaND1 polarity shift observation
Message-ID: <60FB6C3961F84FB185BAC48349695BE2@xxx.xx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Ken,
You can experience the same effect from SO-50 when using circularly
polarized antennas on ground.
SO-50 also have linear antennas for the FM repeater.
I must change between RHCP and LHCP to get maximum signal during a pass.
Sometimes the difference is from zero to a very good signal.
I think it is interaction between the antennas and the rest of the structure
of the satellite combined with the passive attitude control and the angle
you see the satellite in.
73 OZ1MY/Ib
-----Oprindelig meddelelse-----
Fra: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx P? vegne
af Ken Swaggart
Sendt: 04 March 2013 17:03
Til: i8cvs; Amsat - BBs
Emne: [amsat-bb] Re: STRaND1 polarity shift observation
Domenico,
Thanks for sending the K4KJ article.
However my question was why does STRaND1, which only has a whip antenna,
sometimes appear to exhibit circular polarity characteristics? I would
expect a whip antenna transmitting from space to have the same signal
strength on the ground using either RH or LH polarity on my receiving
antenna.
73,
Ken, W7KKE
-----Original Message-----
From: i8cvs
Sent: Monday, March 04, 2013 00:42
To: Ken Swaggart ; Amsat - BBs
Subject: Re: [amsat-bb] STRaND1 polarity shift observation
Hi Ken, W7KKE
The answere to your question is clearly described into the zipped article
"Circular Polarization" by K4KJ, 5 MB long that I have sent to you in
a separate email.
73" de
i8CVS Domenico
----- Original Message -----
From: "Ken Swaggart" <k.swaggart@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Monday, March 04, 2013 5:10 AM
Subject: [amsat-bb] STRaND1 polarity shift observation
> During my last pass at 0332Z, max elevation 45 degrees out over the
Pacific,
> I noticed that STRaND1 was stronger when I selected LHCP while approaching
> TCA. After TCA, RHCP was stronger while it was receding. I believe this
> cubesat uses a whip, so not sure what is causing this.
>
> Anyone have an idea why?
>
> Tnx,
> Ken, W7KKE
> CN75xa
>
>
> _______________________________________________
> 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: 7
Date: Mon, 4 Mar 2013 17:19:53 +0000
From: Matty Cunningham <manxmat@xxxxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Fw: Foxdelta ST-2 / LVB Tracker
Message-ID: <DUB123-W37938B395E0842E6FA098AADFA0@xxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Kyle,
I have an ST2 myself and use an old Cornell Doublier for azimuth, and an
Alliance type U100 for elevation.
I put the control interface with a seperate PSU into a 2U cabinet that was
used for other equipment, along with the transformers/phasing capacitors for
each rotator - I used relays for switching the motors/directions with some
diodes to stop reverse spikes from the relays getting back to the interface
transistors.
I had no problems at all using this with a small dual band 2m/70cm yagi from
Sandpiper, last year I upgraded my antennas and found a few issues with the
controller not wanting to play.
I found if I disconnected my radio from the antennas, I had control of the
rotators - re-installed the original antenna, and finding everything working
again, I worked out I had some sort of earth loop weirdness going on.
My Sandpiper dual bander has a dipole feed for each band, isolated from the
antenna boom, the new larger yagis for each band both have a gamma match,
and grounded booms - this was what caused my issue with my controller.
Switching from an aluminium pole, to fiberglass for the elevation boom fixed
my problem - not sure if this would possibly help with your scenario, it
may be worth looking at.
I would also check to make sure you have run through the calibration
procedure for the interface.
I've successfully used the tracker with various bits of software (HRD
rotator software, SDR V.1 console and others).
If I was to buy another, I would go for Howards LVB version from Amsat.
Good luck with getting it up and running.
Matty
MD0MAN
Date: Sat, 2 Mar 2013 12:19:01 -0600
From: "K&R Yoksh" <yokshs@xxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Fw: Foxdelta ST-2 / LVB Tracker
Message-ID: <156EAB2B86C041DE8991016DDFEFDEE0@xxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=response
Hello Howard,
Thanks for the reply. I have posted on the FoxDelta email group, but
haven't
received a reply. I should mention that I don't think that the ST-2 is
malfunctioning, nor do I think that your code has a problem. I just have a
different type of rotator than the typical Yaesu. It would certainly make
things easier if I did, but it would be quite an ordeal to change the
rotator in my situation.
I did not know the background of the Foxdelta vs. the LVB. I do understand
that Amsat gets a donation with every LVB, and my intention was / is to
donate again to Amsat when I can.
I can certainly see where you're coming from re: the IP. I guess if nothing
else, the ham satellite community as a whole benefits from your public
domain IP, which helps generate more interest in satellites and satellite
operation.
As far as the hardware and software goes, I'll look at the grounding, but I
am thinking that the issue lies in the fact that CDE uses a 12 volt
feedback
POT.. I built a simple resistor voltage divider back when I first got my
Kansas City Tracker, so that the KCT would see 0-5v instead. This approach
gives the KCT (or LVB) the correct voltage range, but I believe it may
lower
the resolution of the feedback system?
I'll also try some ferrites on the leads from the CDE rotator box, in case
transients are to blame.
I'm certainly no programmer, but the software seems to stop the rotator
immediately when the ADC sample value equals the target azimuth value. Once
the antennas stop moving, the final location is different by 20 degrees or
so. Once the rotator stops moving, however, the software doesn't recheck
to
see if the rotator is actually where it needs to be.
My idea was to either change the ADC sample rate, or perhaps add a pause
after the rotator stops, and repeat the routine to "fine tune" position.
This is why I have been trying to recompile your source.. I've already got
PICs programmed with your 0.7 and 0.9 HEX files..
73, many thanks.
Kyle
K0KN
------------------------------
Message: 8
Date: Mon, 4 Mar 2013 13:28:24 -0600
From: Alan <wa4sca@xxxxx.xxx>
To: "'Ken Swaggart'" <k.swaggart@xxxxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: STRaND1 polarity shift observation
Message-ID: <4654F208478F4406B7538873474E728F@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Ken,
To add to what others have said, real CP antennas are not really circular.
They are elliptical, due to slight differences in the lengths of the phasing
harnesses, lack of isolation between the two sets of elements, etc. That
means, even for a perfect linear antenna, directly on the axis, that if you
rotate it there will be preferred directions. As you get further from the
axis, the ellipticity becomes more pronounced. Throw in the fact that the
spacecraft antennas may not, due to interactions, be perfectly linear, and
it is not unexpected to see what you are reporting. A helix antenna, while
not switchable, will be more nearly CP but will normally have a slight
variation.
73s,
Alan
WA4SCA
------------------------------
_______________________________________________
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!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 8, Issue 73
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