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CX2SA > SATDIG 23.04.09 02:29l 985 Lines 28517 Bytes #999 (0) @ WW
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Today's Topics:
1. Re: Satellite packet question/answer -New Packet Satellite
ANUSAT (Nader Omer)
2. Re: Satellite packet question/answer -New PacketSatellite
ANUSAT (Andrew Glasbrenner)
3. Semi-rare grid EL94 will be active this weekend (Bill Dzurilla)
4. Re: Cross Boom (Jeff Yanko)
5. Re: Cross Boom (Joe)
6. Re: Satellite packet question/answer -New PacketSatellite
ANUSAT (Alan P. Biddle)
7. Re: Satellite packet question/answer -New PacketSatellite
ANUSAT (Pete Rowe)
8. Re: Satellite packet question/answer -NewPacketSatellite
ANUSAT (Graham Shirville)
9. Re: Satellite packet question/answer -New PacketSatellite
ANUSAT (Alan P. Biddle)
10. APRS Cubesat LEO constellation (Robert Bruninga)
11. Re: Arrow vs M-Squared Antenna Question (Jack K.)
12. Re: FLTSATCOM Hacked (Robert Bruninga)
13. Re: Satellite packet question/answer -NewPacketSatellite
ANUSAT (Trevor .)
14. Re: Cross Boom (Nigel Gunn G8IFF/W8IFF)
15. Re: Arrow vs M-Squared Antenna Question (Nigel Gunn G8IFF/W8IFF)
----------------------------------------------------------------------
Message: 1
Date: Wed, 22 Apr 2009 12:11:11 -0700 (PDT)
From: Nader Omer <st2nh@xxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New Packet
Satellite ANUSAT
To: amsat bb bb <amsat-bb@xxxxx.xxx>
Message-ID: <149465.26835.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Hi Mark N8MH & All
One more new Packet sat from India!
?
ANUSAT carrying an Amateur Radio payload was launched on Monday April 20 from
the Indian Space Research Organisation (ISRO) Satish Dhawan space centre.
?
The Amateur Radio payload is a 145/435 MHz Digital Store and Forward system
developed by students at the university and the planned orbit was at 550 km
with an inclination of 41 degrees.
?
sourse
http://www.southgatearc.org/news/april2009/anusat_launched.htm
?
?
73's
Nader , st2nh
www.st2nh.com
------------------------------
Message: 2
Date: Wed, 22 Apr 2009 15:23:21 -0400
From: "Andrew Glasbrenner" <glasbrenner@xxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New
PacketSatellite ANUSAT
To: <st2nh@xxxxx.xxx>, "amsat bb bb" <amsat-bb@xxxxx.xxx>
Message-ID: <1D1CD0DAA4534280A5F0948B41BB0493@xxxxxxxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
The frequencies and speed/format have not been released, or little else for
that matter. I'm hopeful, but not going to count my chickens before they
hatch.
73, Drew KO4MA
----- Original Message -----
From: "Nader Omer" <st2nh@xxxxx.xxx>
To: "amsat bb bb" <amsat-bb@xxxxx.xxx>
Sent: Wednesday, April 22, 2009 3:11 PM
Subject: [amsat-bb] Re: Satellite packet question/answer -New
PacketSatellite ANUSAT
Hi Mark N8MH & All
One more new Packet sat from India!
ANUSAT carrying an Amateur Radio payload was launched on Monday April 20
from the Indian Space Research Organisation (ISRO) Satish Dhawan space
centre.
The Amateur Radio payload is a 145/435 MHz Digital Store and Forward system
developed by students at the university and the planned orbit was at 550 km
with an inclination of 41 degrees.
sourse
http://www.southgatearc.org/news/april2009/anusat_launched.htm
73's
Nader , st2nh
www.st2nh.com
_______________________________________________
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, 22 Apr 2009 12:28:34 -0700 (PDT)
From: Bill Dzurilla <billdz.geo@xxxxx.xxx>
Subject: [amsat-bb] Semi-rare grid EL94 will be active this weekend
To: amsat-bb@xxxxx.xxx
Cc: fm-satellite@xxxxxxxxxxx.xxx
Message-ID: <900088.15593.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
If anyone needs EL94 (Florida Keys), I will be in Islamorada this weekend with
my rig and Arrow antenna. Sadly, AO-51 will not be available in V/U mode, so
listen for me via AO-27, SO-50 and, if active, the ISS.
73, Bill NZ5N
------------------------------
Message: 4
Date: Wed, 22 Apr 2009 12:41:14 -0700
From: "Jeff Yanko" <wb3jfs@xxx.xxx>
Subject: [amsat-bb] Re: Cross Boom
To: <kq6ea@xxxxxxx.xxx>, "Joe" <nss@xxx.xxx>, "Billy Simpkins"
<bsimpkins31@xxxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <556AB11BC38A4C45BABD51C289B11A69@xxxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
OK, I see where this is coming into play. So it's possible that the coax
shield could react to the feedpoint system and pattern. Now this raises a
question. If this is the case, has anybody tried a broadband choke balun to
limit this potential problem? If you think about it, the bigger issue with
coax effecting the radiation pattern is improper decoupling of the fed
point. If the outside shield is hot with RF it will radiated and effect the
pattern big time. If the coax is properly decoupled at the fed point the
outside shield will ideally have zero rf current on it and ideally have no
impact on the pattern.
Thoughts?
73,
Jeff WB3JFS
----- Original Message -----
From: "Jim Jerzycke" <kq6ea@xxxxxxx.xxx>
To: "Joe" <nss@xxx.xxx>; "Billy Simpkins" <bsimpkins31@xxxxxxxx.xxx>; "Jeff
Yanko" <wb3jfs@xxx.xxx>
Cc: <amsat-bb@xxxxx.xxx>
Sent: Wednesday, April 22, 2009 11:09 AM
Subject: Re: [amsat-bb] Re: Cross Boom
>
> Because the shield of the coax "looks" like a piece of pipe, and has the
> same effect on the antenna pattern that you're trying to eliminate by
> going to a non-metallic cross-boom.
> Jim KQ6EA
>
>
> --- On Wed, 4/22/09, Jeff Yanko <wb3jfs@xxx.xxx> wrote:
>
>> From: Jeff Yanko <wb3jfs@xxx.xxx>
>> Subject: [amsat-bb] Re: Cross Boom
>> To: "Joe" <nss@xxx.xxx>, "Billy Simpkins" <bsimpkins31@xxxxxxxx.xxx>
>> Cc: amsat-bb@xxxxx.xxx
>> Date: Wednesday, April 22, 2009, 10:55 AM
>> Hi all,
>> I found this line confusing....
>>
>> "But then if you go insulated then do not run the
>> feedline along it either
>> or you just defeated the purpose of the insulated
>> boom."
>>
>> My question is if you run the coax along an insulated
>> crossboom, ie.
>> fiberglass, how could that affect the coupling of the
>> transmission line when
>> the object it is being attached to is
>> "insulated"?
>>
>>
>> 73,
>>
>> Jeff WB3JFS
>>
>>
>>
>>
>>
>> ----- Original Message -----
>> From: "Joe" <nss@xxx.xxx>
>> To: "Billy Simpkins"
>> <bsimpkins31@xxxxxxxx.xxx>
>> Cc: <amsat-bb@xxxxx.xxx>
>> Sent: Wednesday, April 22, 2009 7:06 AM
>> Subject: [amsat-bb] Re: Cross Boom
>>
>>
>> > It all depends on how the elements are mounted.
>> >
>> > If at 45 to 90 degrees from the crossarm, no propblem
>> and use anything,
>> >
>> > But if in the same plane then need insulated
>> crossboom,
>> >
>> > But then if you go insulated then do not run the
>> feedline along it
>> > either or you just defeated the purpose of the
>> insulated boom.
>> >
>> > Billy Simpkins wrote:
>> >
>> >>Is a fiber glass or some other non-conductive
>> material necessary for a
>> >>cross boom? What or the advantages and
>> disadvantages versus a metal one?
>> >>
>> >>Thanks,
>> >>Billy KF0CK
>> >>_______________________________________________
>> >>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
>> >
>>
>>
>> _______________________________________________
>> 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: Wed, 22 Apr 2009 14:56:52 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: Cross Boom
To: Jeff Yanko <wb3jfs@xxx.xxx>
Cc: amsat-bb@xxxxx.xxxx kq6ea@xxxxxxx.xxx
Message-ID: <49EF7684.3080603@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
No,
That will not make any difference.
we are ONLY thinking of the metal in the near field of the antenna,, and
how it effects the radiation pattern as well as impedance of the antenna.
Now add in feedline radiation and you just oopened up a whole new can of
worms.
Jeff Yanko wrote:
> OK, I see where this is coming into play. So it's possible that the
> coax shield could react to the feedpoint system and pattern. Now this
> raises a question. If this is the case, has anybody tried a broadband
> choke balun to limit this potential problem? If you think about it,
> the bigger issue with coax effecting the radiation pattern is improper
> decoupling of the fed point. If the outside shield is hot with RF it
> will radiated and effect the pattern big time. If the coax is properly
> decoupled at the fed point the outside shield will ideally have zero
> rf current on it and ideally have no impact on the pattern.
>
> Thoughts?
>
>
> 73,
>
> Jeff WB3JFS
>
>
> ----- Original Message ----- From: "Jim Jerzycke" <kq6ea@xxxxxxx.xxx>
> To: "Joe" <nss@xxx.xxx>; "Billy Simpkins" <bsimpkins31@xxxxxxxx.xxx>;
> "Jeff Yanko" <wb3jfs@xxx.xxx>
> Cc: <amsat-bb@xxxxx.xxx>
> Sent: Wednesday, April 22, 2009 11:09 AM
> Subject: Re: [amsat-bb] Re: Cross Boom
>
>
>>
>> Because the shield of the coax "looks" like a piece of pipe, and has
>> the same effect on the antenna pattern that you're trying to
>> eliminate by going to a non-metallic cross-boom.
>> Jim KQ6EA
>>
>>
>> --- On Wed, 4/22/09, Jeff Yanko <wb3jfs@xxx.xxx> wrote:
>>
>>> From: Jeff Yanko <wb3jfs@xxx.xxx>
>>> Subject: [amsat-bb] Re: Cross Boom
>>> To: "Joe" <nss@xxx.xxx>, "Billy Simpkins" <bsimpkins31@xxxxxxxx.xxx>
>>> Cc: amsat-bb@xxxxx.xxx
>>> Date: Wednesday, April 22, 2009, 10:55 AM
>>> Hi all,
>>> I found this line confusing....
>>>
>>> "But then if you go insulated then do not run the
>>> feedline along it either
>>> or you just defeated the purpose of the insulated
>>> boom."
>>>
>>> My question is if you run the coax along an insulated
>>> crossboom, ie.
>>> fiberglass, how could that affect the coupling of the
>>> transmission line when
>>> the object it is being attached to is
>>> "insulated"?
>>>
>>>
>>> 73,
>>>
>>> Jeff WB3JFS
>>>
>>>
>>>
>>>
>>>
>>> ----- Original Message ----- From: "Joe" <nss@xxx.xxx>
>>> To: "Billy Simpkins"
>>> <bsimpkins31@xxxxxxxx.xxx>
>>> Cc: <amsat-bb@xxxxx.xxx>
>>> Sent: Wednesday, April 22, 2009 7:06 AM
>>> Subject: [amsat-bb] Re: Cross Boom
>>>
>>>
>>> > It all depends on how the elements are mounted.
>>> >
>>> > If at 45 to 90 degrees from the crossarm, no propblem
>>> and use anything,
>>> >
>>> > But if in the same plane then need insulated
>>> crossboom,
>>> >
>>> > But then if you go insulated then do not run the
>>> feedline along it
>>> > either or you just defeated the purpose of the
>>> insulated boom.
>>> >
>>> > Billy Simpkins wrote:
>>> >
>>> >>Is a fiber glass or some other non-conductive
>>> material necessary for a
>>> >>cross boom? What or the advantages and
>>> disadvantages versus a metal one?
>>> >>
>>> >>Thanks,
>>> >>Billy KF0CK
>>> >>_______________________________________________
>>> >>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
>>> >
>>>
>>>
>>> _______________________________________________
>>> 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: Wed, 22 Apr 2009 15:18:17 -0500
From: "Alan P. Biddle" <APBIDDLE@xxxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New
PacketSatellite ANUSAT
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
Message-ID: <42F3E6944F68473581F251156B5299F9@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Looks interesting, but as Drew said, we shall see what we shall see. So
far, just looking for an object number to look at the orbit.
Alan
WA4SCA
------------------------------
Message: 7
Date: Wed, 22 Apr 2009 13:27:04 -0700 (PDT)
From: Pete Rowe <ptrowe@xxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New
PacketSatellite ANUSAT
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>, APBIDDLE@xxxxxxx.xxx
Message-ID: <26742.80040.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Space-track shows? ANUSAT as object 34808.
One of the papers published about it says the TLM is on 137.4 MHz
73,
Pete
WA6WOA
--- On Wed, 4/22/09, Alan P. Biddle <APBIDDLE@xxxxxx.xxx> wrote:
From: Alan P. Biddle <APBIDDLE@xxxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New PacketSatellite
ANUSAT
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
Date: Wednesday, April 22, 2009, 1:18 PM
Looks interesting, but as Drew said, we shall see what we shall see. So
far, just looking for an object number to look at the orbit.
Alan
WA4SCA
_______________________________________________
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: 8
Date: Wed, 22 Apr 2009 21:59:39 +0100
From: "Graham Shirville" <g.shirville@xxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer
-NewPacketSatellite ANUSAT
To: <APBIDDLE@xxxxxxx.xxx>, "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
Message-ID: <588ED215EC4D4631B9272417F9C1E416@xxxxxxx.xxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hi Alan,
I believe there were three objects - not sure which is Anusat but try 34807
or 34808 or 34809
73
Graham
G3VZV
----- Original Message -----
From: "Alan P. Biddle" <APBIDDLE@xxxxxx.xxx>
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
Sent: Wednesday, April 22, 2009 9:18 PM
Subject: [amsat-bb] Re: Satellite packet question/answer -NewPacketSatellite
ANUSAT
> Looks interesting, but as Drew said, we shall see what we shall see. So
> far, just looking for an object number to look at the orbit.
>
> Alan
> WA4SCA
>
>
>
> _______________________________________________
> 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: Wed, 22 Apr 2009 16:05:05 -0500
From: "Alan P. Biddle" <APBIDDLE@xxxxxx.xxx>
Subject: [amsat-bb] Re: Satellite packet question/answer -New
PacketSatellite ANUSAT
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
Message-ID: <92399B0D12E74C6E92D176EC8B941F12@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Pet and Graham,
Thanks! Will give a listen.
Alan
WA4SCA
------------------------------
Message: 10
Date: Wed, 22 Apr 2009 17:14:17 -0400
From: "Robert Bruninga" <bruninga@xxxx.xxx>
Subject: [amsat-bb] APRS Cubesat LEO constellation
To: "'Andrew Koenig'" <ke5gdb@xxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <761B638DE3214F12A06DBBBC2806E0B4@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
> Will there be any other electronics onboard
> these cubesats, or just the MT-TT4?
> http://www.byonics.com/microtrak/mt-tt4.php
Our particular cubesat will also have a basic stamp pic
processor to do the attitude control to keep it pointed at the
sun. But it is not needed for any other function. All of our
satellites to date flew with no other CPU or processor on board,
other than the TNC itself. Just like this MT-TT4, the KPC3
TNC's we flew before in both PCSATS, ANDE and RAFT have all the
functions you need. Comms, command, inputs, outputs, telemetry,
beacons, digipeater etc.
And even without attitude control a four petal design like we
have as long as there are solar panels on all surfaces and the
petals go back 45 degrees, will have at least half the power as
if it was sun pointing.
http://www.aprs.org/psat.html
Of course we have a 555 timer chip to reset the TNC if it gets
locked up.
Bob, WB4APR
>
>
> On Wed, Apr 22, 2009 at 1:16 PM, Robert Bruninga
> <bruninga@xxxx.xxx> wrote:
>
>
> > A last comment, a LEO would be virtually worthless
> > for Emergency NET communications and HF is still
> > a viable and reliable means of communications...
>
>
> Well, I still think a bunch of 145.825 APRS digipeating
> satellites in LEO that would allow text-messaging from
anywhere
> in the world at any time, downlinked into the
APRS-Internet
> system and hence global internet connectivity is still a
great
> way to go for basic messaging for emergency response.
With just
> 6 such tiny 4" cubesats, you could get a message
in-or-out with
> no more than a half hour wait from the front panel of
your APRS
> mobile radio. With a dozen of these, you could have
global
> communications anywhere instantly or with no more than a
5
> minute wait.
>
> Our goal is to get more of these up there to join the
ISS
> digipeater, but of the 4 we have lanuched so far, all
were
> short-term orbits and so the most we have ever had
operational
> at one time was 3 (PCSAT-1, ANDE and RAFT). That is one
of the
> main reasons we wanted to see ISS on 145.825 to join the
> constellation. ISS was still on 145.800 during most of
the life
> of those three birds (which were all on 145.825)
>
> Today, with 6 AA NiCd's, a 19" whip antennna, and a 3.4"
square
> APRS Microtacker TNC/Radio you can throw together an
APRS
> satellite for under $400. Add cheap solar panels, a lot
of
> sweat equity and then find a school to provide the
$50,000
> launch, and bingo, A LEO satellite with great utility
that
> anyone can use while mobile for text messsaging and
email from
> the front panel of their APRS radio.
>
> Please see the Microtrack TNC/Radio which can serve as
the
> entire Comms, Command, Control and Telemetry module:
>
> http://www.byonics.com/microtrak/mt-tt4.php
>
> And see our cubesat project:
http://www.aprs.org/psat.html
> though this web page needs to be significanly updated..
>
> Bob, WB4APR
>
>
>
> _______________________________________________
> 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
>
>
>
>
>
> --
> Andrew Koenig
>
>
>
------------------------------
Message: 11
Date: Sat, 22 Aug 2009 12:08:28 -0600
From: "Jack K." <kd1pe.1@xxxxx.xxx>
Subject: [amsat-bb] Re: Arrow vs M-Squared Antenna Question
To: <dave@xxxxxx.xxx>, <AMSAT-BB@xxxxx.xxx>
Message-ID: <A77275A8298C4CE7BCCC45D9777CAC13@xxxxxxxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Dave, if you want a more Technical answer, you may feel free to contact me
off the BBS (Direct) and I will get as technical as you like. The simple
version is that at its center, an antenna element is at a null point and it
may (by design) be either free floating (not grounded) or grounded to the
mast. Truthfully it boils down to who designed the antenna and what the
designers preference was... Operationally there is little if any difference
from this standpoint. Constructionally it is easier to make a grounded
element yagi and of course by design they should also (unless it is a really
crappy design and there are some out there) be stronger (more robust) than
the insulated antennas...
Bottom line, don't worry about gain, most advertized figures lie anyway in
that they give a figure devised for their own (not yours the operators)
ends... If the antenna does what you want, then it is a good one, if it
doesn't it is no good for you... Remember the higher the gain the smaller
the radiation pattern and the harder it is to hit a target (think shotgun
Vs. Rifle) The shot gun has less directional gain, and will not shoot as
far, but it is easier to hit a close in target (LEO's) than is the higher
gain (Rifle) antenna...
For all intents and purposes a 3-4 element yagi is all you need on 2 meters
and 4-5 on 435 Mc.
DE KD1PE
Subject: [amsat-bb] Arrow vs M-Squared Antenna Question
>I just received an Arrow and I already had an M-Squared 2m antenna. The
> M-Squared has the elements isolated from the boom by means of rubber
> grommets; the Arrow has the elements attached to the boom and they are not
> isolated. It seems to me that makes the elements, boom, mast and coax
> center
> conductor all grounded. Right?
>
>
> Doesn't that make the Arrow less effective in radiating and in reception?
>
> Dave // DM78qd // KA0SWT
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 12
Date: Wed, 22 Apr 2009 17:19:47 -0400
From: "Robert Bruninga" <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: FLTSATCOM Hacked
To: <eric.fort@xxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <2928D4442DF14E8C8C0304242BEE3BE2@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
> A school to provide the $50,000 launch.....
> Anything from keeping 50 hams from donating
> $1000 a piece and just buying a launch
> - no school involved?
Sure, anyone. I havent priced the latest launch integratiojn
costs from the Cubesat Program recently, but the $50k was their
original plan...
> On Wed, Apr 22, 2009 at 11:16 AM, Robert Bruninga
> <bruninga@xxxx.xxx> wrote:
>
>
> > A last comment, a LEO would be virtually worthless
> > for Emergency NET communications and HF is still
> > a viable and reliable means of communications...
>
>
> Well, I still think a bunch of 145.825 APRS digipeating
> satellites in LEO that would allow text-messaging from
anywhere
> in the world at any time, downlinked into the
APRS-Internet
> system and hence global internet connectivity is still a
great
> way to go for basic messaging for emergency response.
With just
> 6 such tiny 4" cubesats, you could get a message
in-or-out with
> no more than a half hour wait from the front panel of
your APRS
> mobile radio. With a dozen of these, you could have
global
> communications anywhere instantly or with no more than a
5
> minute wait.
>
> Our goal is to get more of these up there to join the
ISS
> digipeater, but of the 4 we have lanuched so far, all
were
> short-term orbits and so the most we have ever had
operational
> at one time was 3 (PCSAT-1, ANDE and RAFT). That is one
of the
> main reasons we wanted to see ISS on 145.825 to join the
> constellation. ISS was still on 145.800 during most of
the life
> of those three birds (which were all on 145.825)
>
> Today, with 6 AA NiCd's, a 19" whip antennna, and a 3.4"
square
> APRS Microtacker TNC/Radio you can throw together an
APRS
> satellite for under $400. Add cheap solar panels, a lot
of
> sweat equity and then find a school to provide the
$50,000
> launch, and bingo, A LEO satellite with great utility
that
> anyone can use while mobile for text messsaging and
email from
> the front panel of their APRS radio.
>
> Please see the Microtrack TNC/Radio which can serve as
the
> entire Comms, Command, Control and Telemetry module:
>
> http://www.byonics.com/microtrak/mt-tt4.php
>
> And see our cubesat project:
http://www.aprs.org/psat.html
> though this web page needs to be significanly updated..
>
> Bob, WB4APR
>
>
>
> _______________________________________________
> 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: 13
Date: Wed, 22 Apr 2009 22:15:47 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
Subject: [amsat-bb] Re: Satellite packet question/answer
-NewPacketSatellite ANUSAT
To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>, Graham Shirville
<g.shirville@xxxxxxxxxx.xxx>
Message-ID: <942421.37158.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Info on Anusat from one of the students Sidharth Balasubramanian at
http://bsidharth1205.googlepages.com/research
73 Trevor M5AKA
--- On Wed, 22/4/09, Graham Shirville <g.shirville@xxxxxxxxxx.xxx> wrote:
> From: Graham Shirville <g.shirville@xxxxxxxxxx.xxx>
> Subject: [amsat-bb] Re: Satellite packet question/answer -NewPacketSatellite
ANUSAT
> To: APBIDDLE@xxxxxxx.xxxx "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
> Date: Wednesday, 22 April, 2009, 9:59 PM
> Hi Alan,
>
> I believe there were three objects - not sure which is
> Anusat but try 34807
> or 34808 or 34809
>
> 73
>
> Graham
> G3VZV
> ----- Original Message -----
> From: "Alan P. Biddle" <APBIDDLE@xxxxxx.xxx>
> To: "'amsat bb bb'" <amsat-bb@xxxxx.xxx>
> Sent: Wednesday, April 22, 2009 9:18 PM
> Subject: [amsat-bb] Re: Satellite packet question/answer
> -NewPacketSatellite
> ANUSAT
>
>
> > Looks interesting, but as Drew said, we shall see what
> we shall see.? So
> > far, just looking for an object number to look at the
> orbit.
> >
> > Alan
> > WA4SCA
> >
> >
> >
> > _______________________________________________
> > 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: 14
Date: Thu, 23 Apr 2009 00:53:23 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel@xxxxx.xxx>
Subject: [amsat-bb] Re: Cross Boom
To: Billy Simpkins <bsimpkins31@xxxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <49EFBC03.6010300@xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
No
None
Billy Simpkins wrote:
> Is a fiber glass or some other non-conductive material necessary for a cross
boom? What or the advantages and disadvantages versus a metal one?
>
------------------------------
Message: 15
Date: Thu, 23 Apr 2009 00:55:42 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel@xxxxx.xxx>
Subject: [amsat-bb] Re: Arrow vs M-Squared Antenna Question
To: dave@xxxxxx.xxx
Cc: AMSAT-BB@xxxxx.xxx
Message-ID: <49EFBC8E.2060209@xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
No, it just makes it a different design.
Dave wrote:
>
> Doesn't that make the Arrow less effective in radiating and in reception?
>
------------------------------
_______________________________________________
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 4, Issue 193
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