| |
CX2SA > SATDIG 23.04.09 01:16l 348 Lines 9726 Bytes #999 (0) @ WW
BID : 27782-CX2SA
Read: GUEST
Subj: AMSAT-BB-digest V4 192
Path: IZ3LSV<IK2XDE<DB0RES<ON0AR<7M3TJZ<HG8LXL<CX2SA
Sent: 090423/0009Z @:CX2SA.LAV.URY.SA #:27782 [Minas] FBB7.00e $:27782-CX2SA
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Send AMSAT-BB mailing list submissions to
amsat-bb@xxxxx.xxx
To subscribe or unsubscribe via the World Wide Web, visit
http://amsat.org/mailman/listinfo/amsat-bb
or, via email, send a message with subject or body 'help' to
amsat-bb-request@xxxxx.xxx
You can reach the person managing the list at
amsat-bb-owner@xxxxx.xxx
When replying, please edit your Subject line so it is more specific
than "Re: Contents of AMSAT-BB digest..."
Today's Topics:
1. Re: Cross Boom (Joe)
2. Re: Cross Boom (Jim Jerzycke)
3. Re: FLTSATCOM Hacked (Robert Bruninga)
4. Re: cross Boom (Nader Omer)
5. Arrow vs M-Squared Antenna Question (Dave)
----------------------------------------------------------------------
Message: 1
Date: Wed, 22 Apr 2009 13:02:38 -0500
From: Joe <nss@xxx.xxx>
Subject: [amsat-bb] Re: Cross Boom
To: Jeff Yanko <wb3jfs@xxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <49EF5BBE.3020605@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Because you now have a metal object (the coax) running along the
fiberglass boom, and this WILL effect the radiation pattern of the
antenna. and possible the match also.
Jeff Yanko wrote:
> 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
>>
>
>
>
------------------------------
Message: 2
Date: Wed, 22 Apr 2009 11:09:52 -0700 (PDT)
From: Jim Jerzycke <kq6ea@xxxxxxx.xxx>
Subject: [amsat-bb] Re: Cross Boom
To: Joe <nss@xxx.xxx>, Billy Simpkins <bsimpkins31@xxxxxxxx.xxx>, Jeff
Yanko <wb3jfs@xxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <437523.80776.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=us-ascii
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: 3
Date: Wed, 22 Apr 2009 14:16:16 -0400
From: "Robert Bruninga" <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: FLTSATCOM Hacked
To: <amsat-bb@xxxxx.xxx>
Message-ID: <0057658040984C4798238310A6011694@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
> 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
------------------------------
Message: 4
Date: Wed, 22 Apr 2009 11:25:31 -0700 (PDT)
From: Nader Omer <st2nh@xxxxx.xxx>
Subject: [amsat-bb] Re: cross Boom
To: amsat bb bb <amsat-bb@xxxxx.xxx>
Message-ID: <469988.16314.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Hi Billy
This link? may help!!
?
http://www.g6lvb.com/fibermetalboom.htm
?
73's
Nader.st2nh
www.st2nh.com
------------------------------
Message: 5
Date: Wed, 22 Apr 2009 12:29:40 -0600
From: "Dave" <dave@xxxxxx.xxx>
Subject: [amsat-bb] Arrow vs M-Squared Antenna Question
To: <AMSAT-BB@xxxxx.xxx>
Message-ID: <85BEC28AD24442999D84D1F39FBC0402@xxxxxxxxxxx>
Content-Type: text/plain; charset="us-ascii"
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?
Dumbo question for the geniuses on this board, but I am wondering why one is
isolated and another isn't.
Dave // DM78qd // KA0SWT
+++++++++++++++++++++++++++++++++++++
------------------------------
_______________________________________________
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 192
****************************************
Read previous mail | Read next mail
| |
