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CX2SA > SATDIG 08.08.08 04:28l 513 Lines 19288 Bytes #999 (0) @ WW
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Subj: AMSAT-BB-digest V3 398
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To : SATDIG@WW
Today's Topics:
1. The Journal and "Progress" (ANTHONY JAPHA)
2. Re: Re polarity control box - again (i8cvs)
3. Re: The Journal and "Progress" (Bruce Robertson)
4. Re: [!! SPAM] Re: The Journal and "Progress" (ANTHONY JAPHA)
5. Re: re Polarity control box - again (i8cvs)
6. data port rig/tnc cable (Mr Jeffrey L Ross)
7. Santa Barbara Hamfest Demo Sunday (Ken Owen)
8. Video of Falcon 1 3 malfunction (Bruce Robertson)
----------------------------------------------------------------------
Message: 1
Date: Wed, 6 Aug 2008 18:07:13 -0400
From: "ANTHONY JAPHA" <tjjapha(AT)earthlink.net>
Subject: [amsat-bb] The Journal and "Progress"
To: "amsat-bb" <amsat-bb(AT)amsat.org>
Message-ID: <380-2200883622713656(AT)earthlink.net>
Content-Type: text/plain; charset=US-ASCII
Greetings All,
Just received the May/June Journal. It is extremely disheartening.
For the 2nd issue in a row, there's no status report on Eagle (using the term
in the broad sense as W2GPS uses it, to include the possibility of a
rideshare). In Rick's Apogee View, there are the most vague references to
progress, but the whole piece could have been written long, long ago. No
conceivable definition of a progress report would include that writeup. There
is not a single specific citation of real progress. We can only assume there
has been none.
This criticism has nothing to do with the difficulty in identifying an
affordable launch opportunity, the discussion of which has been lengthy here.
It has to do with getting ready for a launch if and when it appears possible.
At one level, this is a chicken and egg problem; without a specific launch
opportunity, what is to be built? But, the way to get out of a chicken and
egg situation is to acquire either a chicken or an egg. We have neither.
Without a chicken there'll never be an egg, and vice versa.
Let's get a bird basically ready to go, i.e. designed, prototyped, tested,
refined, etc. Where are we on these steps? How much more money is needed to
get us there? Is the prospect of raising that amount of money good or is it
as grim as being able to afford a launch?
I continue to think that there is enough talent here to do the real stuff.
That has been demonstrated many times. What there is little evidence of is
the capacity to manage the effort in a way that improves the prospects of
pulling the pieces (finance, planning, decision making) together.
If I am wrong about all this, then please show the evidence. Just where are
we on the many pieces that will comprise the bird? When will they be
finished? How much will it cost? etc, etc, etc. I don't buy "progress" when
none is apparent. Please make it apparent to us.
73,
Tony, N2UN
LM 183
------------------------------
Message: 2
Date: Thu, 7 Aug 2008 00:08:42 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: Re polarity control box - again
To: "Angus" <angus(AT)young5769.freeserve.co.uk>, "AMSAT-BB"
<amsat-bb(AT)amsat.org>
Message-ID: <002201c8f810$fdd7c280$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Angus" <angus(AT)young5769.freeserve.co.uk>
To: <amsat-bb(AT)amsat.org>
Sent: Wednesday, August 06, 2008 5:06 PM
Subject: [amsat-bb] Re polarity control box - again
> Hi all, its me again, sorry.
> OK got the 2mtr polarity control box working and very pleased, except for
> one very small item.
> LHCP never seemed to me to be 90 degrees out of phase with RHCP, never had
> the large drop in signal I expected.
> OK time for a bit or research and looked in to my VHF/UHF manual and found
> the pages and guess what, the design we have been using is wrong, or so I
> think, please correct me if I am wrong.
> OK both yagis have a 1/4 wave 75 ohm matching system to allow the system
> back to work with 2 x 50 ohm yagis in parallel, in case anyone forgets, so
> for Vertical both yagis fed in phase, for Horizontal the 135 degrees yagi
> is
> fed with a 1/2 wave of 50 ohm line to delay it by 180 degrees, no problems
> so far.
Hi Gus M0IKB
In a previous message dated 23 july you writes:
"The control box is a copy off the G6LVB website and the VHF/UHF manua
l 4th edition"
For this reason I visited the G6LVB site at
http://www.g6lvb.com/remotepolarization.htm
And I found the polarization switching diagram absolutely correct.
> For RHCP the 45 degrees yagi is fed with a 1/4 wavelength of 50 ohm delay
> line and again no problems.
> NOW HERE'S THE RUB!
> For LHCP we feed the 135 degrees yagi with a 1/4 wavelength of 50 ohm
> line, woops the system has a 1/2 wavelength of 50 ohm line!
> So instead of feeding as we should we are feeding it to make it simpler
> than it should be. Hence I was never happy that LHCP was never quite 90
> degrees out with RHCP.
What you don't understand is that for LHCP the -45? yagi is fed with a 1/4
wavelenght of 50 ohm delay line because RL1 is ON and RL2 is OFF
For RHCP the +45? yagi is fed with a 1/2 wavelenght of 50 ohm delay
line because RL1 is ON and RL2 is ON
But when RL1 and RL2 are both ON for RHCP then the 1/4 wavelengt delay
line is still in circuit in series with the -45? yagi so that the resultant
delay line in series with the +45? yagi for RHCP is the difference of
1/2 -1/4 = 1/4 wavelenght and this difference make a resultant phase shift
of 90? in series with the other +45? yagi
In other words for LHCP only a 1/4 wavelength delay line is in series with
the -45? yagi and for RHCP only a 1/4 wavelenght delay line is in series
with the +45? yagi so that between LHCP and RHCP there is a phase difference
of 90? that is correct.
> So quite possibly we are going to get some form of strange oval type of
> polarity anyone take a guess at its true nature, I may have a play around
> with one of the antenna programs and see what comes out.
> Am I wrong completely on this or is it the better to have it off a little
> on LHCP to get the other 3 polarities correct?
If you did things like the schematic diagram of G6LVB shows all 4
polarities are completely correct.
> Sorry for boring some of you.
> regards
> Gus M0IKB
73" de
i8CVS Domenico
------------------------------
Message: 3
Date: Wed, 6 Aug 2008 20:34:47 -0300
From: "Bruce Robertson" <ve9qrp(AT)gmail.com>
Subject: [amsat-bb] Re: The Journal and "Progress"
To: tjjapha(AT)earthlink.net
Cc: Amsat-Bb <amsat-bb(AT)amsat.org>
Message-ID:
<49657a760808061634hdc5215fj9282617fc92c311c(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
On Wed, Aug 6, 2008 at 7:07 PM, ANTHONY JAPHA <tjjapha(AT)earthlink.net>
wrote:
> Greetings All,
> Just received the May/June Journal. It is extremely disheartening.
>
> For the 2nd issue in a row, there's no status report on Eagle (using the
term in the broad sense as W2GPS uses it, to include the possibility of a
rideshare). In Rick's Apogee View, there are the most vague references to
progress, but the whole piece could have been written long, long ago. No
conceivable definition of a progress report would include that writeup. There
is not a single specific citation of real progress. We can only assume there
has been none.
>
> This criticism has nothing to do with the difficulty in identifying an
affordable launch opportunity, the discussion of which has been lengthy here.
It has to do with getting ready for a launch if and when it appears possible.
At one level, this is a chicken and egg problem; without a specific launch
opportunity, what is to be built? But, the way to get out of a chicken and
egg situation is to acquire either a chicken or an egg. We have neither.
Without a chicken there'll never be an egg, and vice versa.
>
> Let's get a bird basically ready to go, i.e. designed, prototyped, tested,
refined, etc. Where are we on these steps? How much more money is needed to
get us there? Is the prospect of raising that amount of money good or is it
as grim as being able to afford a launch?
>
> I continue to think that there is enough talent here to do the real stuff.
That has been demonstrated many times. What there is little evidence of is
the capacity to manage the effort in a way that improves the prospects of
pulling the pieces (finance, planning, decision making) together.
>
> If I am wrong about all this, then please show the evidence. Just where
are we on the many pieces that will comprise the bird? When will they be
finished? How much will it cost? etc, etc, etc. I don't buy "progress" when
none is apparent. Please make it apparent to us.
>
> 73,
> Tony, N2UN
> LM 183
Tony and everyone --
Forgive me if I'm repeating what you know; I don't have the new issue
of the Journal, I'm just stating what I understand from other sources.
In particular, the AMSAT-UK symposium two weekends ago had a long
presentation on P3E. It is supposed to be done by the end of the year.
Launch costs are prohibitively high, many millions of euros. However,
AMSAT-DL is presenting P3E and P5A as a package to the German national
space agency and hopes it might receive funding in that way. P3E would
be the test-bed for P5A.
I know you are not asking about this specifically, but I thought at
the time that it did not get sufficient publicity on the bb, so I'm
writing it here. I understand the presentations will be published
online once the video is tidied up. The one on P5A is very
interesting, as is the one on Delfi N3xt. After the presentation on
P5A, I started pricing a dish :-)
73, Bruce
VE9QRP
------------------------------
Message: 4
Date: Wed, 6 Aug 2008 19:59:23 -0400
From: "ANTHONY JAPHA" <tjjapha(AT)earthlink.net>
Subject: [amsat-bb] Re: [!! SPAM] Re: The Journal and "Progress"
To: "Bruce Robertson" <ve9qrp(AT)gmail.com>
Cc: amsat-bb <amsat-bb(AT)amsat.org>
Message-ID: <380-22008836235923718(AT)earthlink.net>
Content-Type: text/plain; charset=US-ASCII
Hi Bruce,
Good to hear from you. The news about P3E completion is very good. If the
Mars connection helps to sell it, that's good strategy.
What DX have you worked recently?
73,
Tony, N2UN
> [Original Message]
> From: Bruce Robertson <ve9qrp(AT)gmail.com>
> To: <tjjapha(AT)earthlink.net>
> Cc: Amsat-Bb <amsat-bb(AT)amsat.org>
> Date: 8/6/2008 7:34:48 PM
> Subject: [!! SPAM] Re: [amsat-bb] The Journal and "Progress"
>
> On Wed, Aug 6, 2008 at 7:07 PM, ANTHONY JAPHA <tjjapha(AT)earthlink.net>
wrote:
> > Greetings All,
> > Just received the May/June Journal. It is extremely disheartening.
> >
> > For the 2nd issue in a row, there's no status report on Eagle (using
the term in the broad sense as W2GPS uses it, to include the possibility of
a rideshare). In Rick's Apogee View, there are the most vague references
to progress, but the whole piece could have been written long, long ago.
No conceivable definition of a progress report would include that writeup.
There is not a single specific citation of real progress. We can only
assume there has been none.
> >
> > This criticism has nothing to do with the difficulty in identifying an
affordable launch opportunity, the discussion of which has been lengthy
here. It has to do with getting ready for a launch if and when it appears
possible. At one level, this is a chicken and egg problem; without a
specific launch opportunity, what is to be built? But, the way to get out
of a chicken and egg situation is to acquire either a chicken or an egg.
We have neither. Without a chicken there'll never be an egg, and vice
versa.
> >
> > Let's get a bird basically ready to go, i.e. designed, prototyped,
tested, refined, etc. Where are we on these steps? How much more money is
needed to get us there? Is the prospect of raising that amount of money
good or is it as grim as being able to afford a launch?
> >
> > I continue to think that there is enough talent here to do the real
stuff. That has been demonstrated many times. What there is little
evidence of is the capacity to manage the effort in a way that improves the
prospects of pulling the pieces (finance, planning, decision making)
together.
> >
> > If I am wrong about all this, then please show the evidence. Just
where are we on the many pieces that will comprise the bird? When will
they be finished? How much will it cost? etc, etc, etc. I don't buy
"progress" when none is apparent. Please make it apparent to us.
> >
> > 73,
> > Tony, N2UN
> > LM 183
>
> Tony and everyone --
>
> Forgive me if I'm repeating what you know; I don't have the new issue
> of the Journal, I'm just stating what I understand from other sources.
> In particular, the AMSAT-UK symposium two weekends ago had a long
> presentation on P3E. It is supposed to be done by the end of the year.
> Launch costs are prohibitively high, many millions of euros. However,
> AMSAT-DL is presenting P3E and P5A as a package to the German national
> space agency and hopes it might receive funding in that way. P3E would
> be the test-bed for P5A.
>
> I know you are not asking about this specifically, but I thought at
> the time that it did not get sufficient publicity on the bb, so I'm
> writing it here. I understand the presentations will be published
> online once the video is tidied up. The one on P5A is very
> interesting, as is the one on Delfi N3xt. After the presentation on
> P5A, I started pricing a dish :-)
>
> 73, Bruce
> VE9QRP
------------------------------
Message: 5
Date: Thu, 7 Aug 2008 03:46:08 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: re Polarity control box - again
To: "Angus" <angus(AT)young5769.freeserve.co.uk>, "AMSAT-BB"
<amsat-bb(AT)amsat.org>
Message-ID: <002701c8f82f$5dc67e20$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Angus" <angus(AT)young5769.freeserve.co.uk>
To: <amsat-bb(AT)amsat.org>
Sent: Wednesday, August 06, 2008 7:10 PM
Subject: [amsat-bb] re Polarity control box - again
> Hi Mak, thanks for reply.
> The problems occur when we go and try and make the polarity control unit
remote controlled. I have a fully working manual unit here in the shack and
is 100% fine.
> However the remote unit I built use's relays to add in extra lengths of
50ohm coax as a delay line (a 1/4 wave on the -45degree yagi, and a
1/2wavelength on the +45degree yagi.)
> This system I have seen used by very many operators and also some
comercial units, however with just the 2 delay lines the LHCP will never
really be LHCP, it needs an extra set of relays to switch in the other
1/4wave delay line.
> I was just wondering if anyone else had seen this or have I just
misunderstood the circuit somehow.
> Any thoughts would be appreaciated.
> regards
> Gus M0IKB
>
Hi Gus M0IKB
In a previous message dated 23 july you writes:
"The control box is a copy off the G6LVB website and the VHF/UHF manua
l 4th edition"
For this reason I visited the G6LVB site at
http://www.g6lvb.com/remotepolarization.htm
And I found the polarization switching diagram absolutely correct.
For LHCP the -45? yagi is fed with a 1/4 wavelenght of 50 ohm delay
line because RL1 is ON and RL2 is OFF
For RHCP the +45? yagi is fed with a 1/2 wavelenght of 50 ohm delay
line because RL1 is ON and RL2 is ON
What you missed is that when RL1 and RL2 are both ON for RHCP then
the 1/4 wavelengt delay line is still in circuit in series with the -45?
yagi so that the resultant delay line in series with the +45? yagi for RHCP
is made by the difference of 1/2 -1/4 = 1/4 wavelenght and this difference
generates a resultant phase shift of 90? in series with the other +45? yagi.
In other words for LHCP only a 1/4 wavelength delay line is in series with
the -45? yagi and for RHCP only a 1/4 wavelenght delay line is in series
with the +45? yagi so that between LHCP and RHCP there is a phase difference
of 90? and that is true only if the -45? and the +45? yagi are mounted in
the same plane over the boom and if the coax line between RL1 and the -45?
yagi have the same lenght of the coax line between RL2 and the +45? yagi.
The above circuit described by G6LVB was first designed by H. Stoll,
DF7SO and published in VHF COMMUNICATIONS 1/1980 pages
33-34-35
The main advantage of this circuit is that if all 4 coaxial relays are of
the same type i.e. they have the same physical lenght when cutting the
coax cable delay lines it is not necessary to take the lenght of each relay
into account.
I have used the above designe in 2 meters for several years beginning with
OSCAR-10 but with minor changes I have applied the same concept
to a 70 cm crossed yagi KLM 435-40CX as described in the article
" Switching Four Polarizations on a 70 cm Crossed Yagi"
AMSAT Journal march/april 2007 Part-1 and may/june 2007 Part-2
73" de
i8CVS Domenico
------------------------------
Message: 6
Date: Wed, 6 Aug 2008 21:04:03 -0400
From: "Mr Jeffrey L Ross" <radiooperator(AT)comcast.net>
Subject: [amsat-bb] data port rig/tnc cable
To: "amsat" <amsat-bb(AT)amsat.org>
Message-ID: <000501c8f829$7d460eb0$6401a8c0(AT)hamshackcomputer>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
hi folks, well I'm. halfway there in setting up a downlink/uplink data
station for sats. So far, a local, way off station can copy me but I can not
copy him. Was wondering if my wires are right.
heres what i have:
tnc:recv. -rig :9600 out
tnc:xmit - rig :data in
tnc:ptt -rig :ptt
tnc:grnd rig:grnd
pk 96 - ft 857
sound right? if not please let me know,tks
still trying for go-32. /anyone got the status, web aprs page get
updated/running yet?
kc8gkf
------------------------------
Message: 7
Date: Thu, 7 Aug 2008 10:20:44 -0700
From: "Ken Owen" <n6kth(AT)n6kth.com>
Subject: [amsat-bb] Santa Barbara Hamfest Demo Sunday
To: <amsat-bb(AT)amsat.org>
Message-ID: <001801c8f8b1$ed94a220$2e01a8c0(AT)CIR2>
Content-Type: text/plain; charset="us-ascii"
Hi folks:
Your assistance is requested to help make my demo at the Santa Barbara
Amateur Radio Club's hamfest on Sunday a success. I will be providing demos
during the 10 Aug, 15:55 AO-51 pass and the 10 Aug 21:06 AO-27 pass. We'd
certainly appreciate some contacts.
Thanks!
Ken Owen, N6KTH
AMSAT Area Coordinator
------------------------------
Message: 8
Date: Thu, 7 Aug 2008 14:25:25 -0300
From: "Bruce Robertson" <ve9qrp(AT)gmail.com>
Subject: [amsat-bb] Video of Falcon 1 3 malfunction
To: Amsat-Bb <amsat-bb(AT)amsat.org>
Message-ID:
<49657a760808071025n145252a5p28b66c68219a3ca6(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
SpaceX has announced that the problem with the last launch was that
the first stage regenerative engine continued burning longer than they
expected. It therefore bumped into the second stage after separation.
A new downward looking video that includes this action is available
at:
http://mfile.akamai.com/22165/wmv/spacex.download.akamai.com/22165/F1-003.asx
73, Bruce
VE9QRP
------------------------------
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End of AMSAT-BB Digest, Vol 3, Issue 398
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