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CX2SA > SATDIG 26.07.08 19:42l 754 Lines 25718 Bytes #999 (0) @ WW
BID : 21229_CX2SA
Read: GUEST
Subj: AMSAT-BB-digest V3 376
Path: IZ3LSV<IV3SCP<SR1BSZ<F4BWT<YO6PLB<CX2SA
Sent: 080726/1739Z @:CX2SA.LAV.URY.SA #:21229 [Minas] FBB7.00e $:21229_CX2SA
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Vertical MOXON antennas for satellites (WB2LLP)
2. Re: FO-29 is back again ! (Alan Cresswell)
3. Re: Dish surface 'flatness' (Dave Guimont)
4. Re: Dish surface 'flatness' (THOMAS F DAVIS)
5. FO-29 (Frank Woolfe)
6. Re: Dish surface 'flatness' (Franklin Antonio)
7. Re: Dish surface 'flatness' (Art McBride)
8. Re: VHF UHF Rig (Nigel Gunn G8IFF/W8IFF)
9. Re: Dish surface 'flatness' (Nigel Gunn G8IFF/W8IFF)
10. Re: Dish surface 'flatness' (Nigel Gunn G8IFF/W8IFF)
11. DELFIC3 Transponder report (Rob Hardenberg PE1ITR)
12. Re crossed yagi question. (Angus)
13. Delfi-N3xt (Bruce Robertson)
14. go-32 techsat1b (Mr Jeffrey L Ross)
15. go-32 techsat1b (Mr Jeffrey L Ross)
16. Re: Re crossed yagi question. (i8cvs)
17. Re: Delfi-N3xt (David - KG4ZLB/M?ZLB)
----------------------------------------------------------------------
Message: 1
Date: Fri, 25 Jul 2008 20:58:18 -0400
From: WB2LLP <wb2llp(AT)optonline.net>
Subject: [amsat-bb] Vertical MOXON antennas for satellites
To: AMSAT -BB <AMSAT-BB(AT)AMSAT.ORG>
Message-ID: <001801c8eeba$b14b29c0$6401a8c0(AT)gene>
Content-Type: text/plain; charset=iso-8859-1
My somewhat porous memory says that L. B. Cebik wrote a couple of articles on
using vertical Moxon antennas to create omni-directional 144 and 432 antennas
for satellite frequencies. I can not find those articles in my shack. Is
there someone with a better organized magazine collection who can tell me what
magazine and issue.?
TNX es 73 de WB2LLP Gene
------------------------------
Message: 2
Date: Sat, 26 Jul 2008 01:12:04 -0000
From: "Alan Cresswell" <alancresswell(AT)xtra.co.nz>
Subject: [amsat-bb] Re: FO-29 is back again !
To: <amsat-bb(AT)amsat.org>
Message-ID: <002501c8eebc$9e43b980$0401010a(AT)Dell1>
Content-Type: text/plain; charset="us-ascii"
Hi all
FO-29 excellent downlink signals over ZL on the 0007 UT pass today (5w for
S9 sig down).
Not long out of eclipse at AOS but no problem entire pass.
Alan
ZL2BX
-----Original Message-----
From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] On
Behalf Of SV1BSX
Sent: Friday, 25 July 2008 23:06
To: eu-amsat(AT)yahoogroups.com
Cc: amsat-bb(AT)amsat.org
Subject: [amsat-bb] FO-29 is back again !
Hello all,
after Robert-G8ATE's report on Amsat-BB, this evening I tried together with
my friend
Dimitris, SW1JGW, a test on FO-29.
Well, yes indeed, the Satellite is active again ! Just after the AOS we
heard clear
the Beacon, and then I had a nice QSO with SW1JGW (21:36Z) ! After that I
changed
my frequency a bit lower and I had a 2nd QSO with DL6HP (21:38 Z).
Both, Dimitris and I, we were QRP ! 5 Watts for Uplink were enough for
excellent return
signals on Downlink. By using QRP we tried to avoid any overloading of the
bird.
The Satellite was really Booming, always 55 - 59 with "crystal audio".
However, at 21:38 my return-signal rapidly decreased, but even much lower it
was easily readable.
After that I interrupted my TX and I return onto Beacon frequency. Q5 now,
but still "clear" !
Later I noticed that on my tracking software, precisely at this time the
Satellite came on a new Eclipse !
So, probably the old-Batteries are not strong enough in order to support the
same Downlink-power
in eclipse, like that on Sunlight. Also I observed some FMing at this point
and I lost the
signal before the LOS, but on this direction I have not "clear horizon" (but
High buildings),
so I can't say with accuracy if the Satellite was still "ON" or not. Sorry !
Anyway, the FO-29 is back again ! Great news !
CU on FO-29 !
73 de Mak, SV1BSX
Email: sv1bsx "AT" yahoo .gr
URL : http://sv1bsx.50webs.com
_______________________________________________
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Not an AMSAT-NA member? Join now to support the amateur satellite program!
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------------------------------
Message: 3
Date: Thu, 24 Jul 2008 17:56:54 -0700
From: Dave Guimont <dguimon1(AT)san.rr.com>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: vk1kep(AT)gmail.com
Cc: amsat-bb(AT)amsat.org
Message-ID:
<20080726005724.ENLW18001.cdptpa-omta05.mail.rr.com(AT)Dave.san.rr.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed
>The mesh covering is metaphorical, rather than actual. I watched the
>dish on its back while as a group of small children rolled the dish back
>and forth and trampled holes in the mesh. That's the reason I was able
>to ask for it. "Please take it away," was the manager's reply to my query.
>
>Now, I need to re-mesh the dish, but I need to decide what 'flatness'
>('true-ness') the surface should be. There has to be a formula, that
>encompasses things like: frequency of operation, curvature or focus
>distance, etc.
Peter,
I'm sure there some on here than can answer your questions accurately.
But I can tell you my experience...I acquired an open framework dish,
It's about 35". I cut gores the size of the framework, with a slight overlap,
and wired them as tightly as I could to the frame....I cut them about
2" longer than the radius, and the extension conformed nicely to the
curve of the dish...In an attempt to get a 39" dish...
I homebrew all my feeds, and it worked very successfully on AO40 at
2.4 gigs...You did not mention a frequency, and of course that is
very important..
73, Dave, WB6LLO
dguimon1(AT)san.rr.com
Disagree: I learn....
Pulling for P3E...
------------------------------
Message: 4
Date: Fri, 25 Jul 2008 20:12:15 -0700 (PDT)
From: THOMAS F DAVIS <tfdavis(AT)snet.net>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: vk1kep(AT)gmail.com, amsat-bb(AT)amsat.org
Message-ID: <204811.52346.qm(AT)web81607.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Hi Peter:
I assume that the dish is a paraboloidal reflector. Can you determine the
focal length and the f/ ratio? What was the original size of the mesh holes?
I checked with Skolnick's Radar Handbook, and there was no information with
regards to your question, just equations on how to create the paraboloidal
form. From my experience with optical paraboloids I can state that it is
widely expected that such mirrors have a deviation over their diameter of no
more than 1/4 of a wave (hmm, where have we seen that number in antenna design
before?). Due to the Rayleigh limit, little gain is added if the accuracy is
increased beyond 1/8 of a wave.
The ARRL Antenna Handbook 19th edition states on page 19-19 regarding
"Parabolic Gain Versus Error": "Each time all the errors are halved, the
frequency of maximum gain is doubled".
Hope this helps.
Tom W1TFD
Peter Ellis <vk1kep(AT)gmail.com> wrote: I am now the proud owner of a very
'second-hand' 3m mesh-covered
skeleton dish.
The mesh covering is metaphorical, rather than actual. I watched the
dish on its back while as a group of small children rolled the dish back
and forth and trampled holes in the mesh. That's the reason I was able
to ask for it. "Please take it away," was the manager's reply to my query.
Now, I need to re-mesh the dish, but I need to decide what 'flatness'
('true-ness') the surface should be. There has to be a formula, that
encompasses things like: frequency of operation, curvature or focus
distance, etc.
I've done some looking online, but can't find it readily.
Suggestions, and discussion, please?
Please note: If you're going to also make product, brand name, or
supplier suggestions, then be generic as suppliers and products in VK
(Australia) will differ from where most list members will be sited.
With thanks,
Peter
VK1KEP
_______________________________________________
Sent via AMSAT-BB(AT)amsat.org. 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: Sat, 26 Jul 2008 12:48:23 +0930
From: "Frank Woolfe" <frankwoolfe(AT)optusnet.com.au>
Subject: [amsat-bb] FO-29
To: <amsat-bb(AT)amsat.org>
Message-ID: <200807260318.m6Q3IQQD012785(AT)mail04.syd.optusnet.com.au>
Content-Type: text/plain; charset="us-ascii"
Great contacts with ZL2BX and ZL1BVA on FO29's 0200UTC pass from the centre
of VK "PF88jt". It seems another "Blast from the past" has come back to life
(well done fella's) Unfortunately when it got further north the same problem
as always north of VK, the 2m Rx bombarded with every Pirate in Indonesia,
Philippines, and Malaysia etc...Who would build an uplink on 2m these days
stick to the tried and proven 70cm up 2m down, the only way to go...
Frank VK5MFW
------------------------------
Message: 6
Date: Fri, 25 Jul 2008 21:35:16 -0700
From: Franklin Antonio <antonio(AT)qualcomm.com>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: "vk1kep(AT)gmail.com" <vk1kep(AT)gmail.com>
Cc: "amsat-bb(AT)amsat.org" <amsat-bb(AT)amsat.org>
Message-ID:
<5b0a690f-f233-4d43-a44a-064f927f04f3(AT)nasanexhc02.na.qualcomm.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 03:00 PM 7/25/2008, Peter Ellis wrote:
>Now, I need to re-mesh the dish, but I need to decide what 'flatness'
>('true-ness') the surface should be. There has to be a formula, that
>encompasses things like: frequency of operation, curvature or focus
>distance, etc.
Focal length, f/d, etc are irrelevant. The thing that is relevant is
wavelength of your signal. You want the variations in the dish's
surface to be small relative to a wavelength. 1/4 wavelength is
ok. 1/8th wavelength is better. Better than that matters not much.
Its not to hard to get an intuitive feel for what is going
on. Suppose you have a dish that is a perfect paraboloid, except for
one little dent that's a little farther from the focus. Suppose the
dent is 1/2 wavelength farther from the focus than the rest of the
dish. The signal that reflects off of that dent will be 1/2
wavelength late, in other words 180 degrees out of phase with the
rest of the signal, and will therefore SUBTRACT from the rest of the
signal. That isn't good. That's a clue that 1/2 wavelength is too
much variation. You can go thru the same sort of thinking with a 1/4
wavelength dent and see that the effect is much smaller, etc.
------------------------------
Message: 7
Date: Fri, 25 Jul 2008 22:17:14 -0700
From: "Art McBride" <kc6uqh(AT)cox.net>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: <vk1kep(AT)gmail.com>, <amsat-bb(AT)amsat.org>
Message-ID: <004b01c8eede$ddb66e10$0200a8c0(AT)kc6uqh>
Content-Type: text/plain; charset="us-ascii"
Peter,
I suggest that the surface irregularities be less than 1/8 Wave length.
Parabolic shape is important. I recommend some excellent practical advice
and charts in the VHF/UHF Manual published by the RSGB. It is easy to
understand and well written.
Art, KC6UQH
-----Original Message-----
From: amsat-bb-bounces(AT)amsat.org [mailto:amsat-bb-bounces(AT)amsat.org] On
Behalf Of Peter Ellis
Sent: Friday, July 25, 2008 3:00 PM
To: amsat-bb(AT)amsat.org
Subject: [amsat-bb] Dish surface 'flatness'
I am now the proud owner of a very 'second-hand' 3m mesh-covered
skeleton dish.
The mesh covering is metaphorical, rather than actual. I watched the
dish on its back while as a group of small children rolled the dish back
and forth and trampled holes in the mesh. That's the reason I was able
to ask for it. "Please take it away," was the manager's reply to my query.
Now, I need to re-mesh the dish, but I need to decide what 'flatness'
('true-ness') the surface should be. There has to be a formula, that
encompasses things like: frequency of operation, curvature or focus
distance, etc.
I've done some looking online, but can't find it readily.
Suggestions, and discussion, please?
Please note: If you're going to also make product, brand name, or
supplier suggestions, then be generic as suppliers and products in VK
(Australia) will differ from where most list members will be sited.
With thanks,
Peter
VK1KEP
_______________________________________________
Sent via AMSAT-BB(AT)amsat.org. 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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------------------------------
Message: 8
Date: Sat, 26 Jul 2008 07:48:22 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel(AT)ngunn.net>
Subject: [amsat-bb] Re: VHF UHF Rig
To: Andrew Harris <andrew.unit(AT)gmail.com>
Cc: AMSAT-BB <amsat-bb(AT)AMSAT.Org>
Message-ID: <488AD6C6.50408(AT)ngunn.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Does this "ocean-deployed robot" have it's own amateur radio license to allow
it to transmit to the satellite?
Andrew Harris wrote:
> Hi everyone,
>
> Is there a radio that is small and lightweight that I could
> interface to a computer easily to receive and transmit packets to
> AO-51? I need one that I would not have to tinker with by hand; I
> want to use the radio (and the AO-51 pacsat) as the primary means to
> communicate with an ocean-deployed robot. Obviously my hand would not
> be there to correct for doppler, etc.
>
> -andrew
------------------------------
Message: 9
Date: Sat, 26 Jul 2008 07:52:46 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel(AT)ngunn.net>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: vk1kep(AT)gmail.com
Cc: amsat-bb(AT)amsat.org
Message-ID: <488AD7CE.6040801(AT)ngunn.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I believe you should be looking at no bumps, holes etc of more than one tenth
(1/10) of a wavelength.
Obviously better than that will benefit performance.
Peter Ellis wrote:
> I am now the proud owner of a very 'second-hand' 3m mesh-covered
> skeleton dish.
>
> The mesh covering is metaphorical, rather than actual. I watched the
> dish on its back while as a group of small children rolled the dish back
> and forth and trampled holes in the mesh. That's the reason I was able
> to ask for it. "Please take it away," was the manager's reply to my query.
>
> Now, I need to re-mesh the dish, but I need to decide what 'flatness'
> ('true-ness') the surface should be. There has to be a formula, that
> encompasses things like: frequency of operation, curvature or focus
> distance, etc.
>
> I've done some looking online, but can't find it readily.
>
> Suggestions, and discussion, please?
>
> Please note: If you're going to also make product, brand name, or
> supplier suggestions, then be generic as suppliers and products in VK
> (Australia) will differ from where most list members will be sited.
>
> With thanks,
> Peter
> VK1KEP
> _______________________________________________
> Sent via AMSAT-BB(AT)amsat.org. 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
>
--
<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
Nigel A. Gunn. G8IFF W8IFF (was KC8NHF)
1865 El Camino Drive, Xenia, OH 45385-1115, USA 937 825 5032
e-mail nigel(AT)ngunn.net www http://www.ngunn.net
Member of ARRL, GQRP #11396, QRPARCI #11644, SOC #548, Flying Pig #385,
Dayton ARA #2128, AMSAT-NA LM-1691, AMSAT-UK, MKARS,
ALC
<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
------------------------------
Message: 10
Date: Sat, 26 Jul 2008 07:59:10 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel(AT)ngunn.net>
Subject: [amsat-bb] Re: Dish surface 'flatness'
To: Franklin Antonio <antonio(AT)qualcomm.com>
Cc: "amsat-bb(AT)amsat.org" <amsat-bb(AT)amsat.org>, "vk1kep(AT)gmail.com"
<vk1kep(AT)gmail.com>
Message-ID: <488AD94E.6030301(AT)ngunn.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Surely a signal that reflects off a half wavelength dent will be one
wavelength late, half a wavelength getting to the dish and half a
wavelength coming back. So a dent (or bump) 1/4 wavelength will cause a 180
deg shift. I would suggest that your dish needs to be better than
(my rule of thumb) 1/10 wavelenth accuracy.
> Its not to hard to get an intuitive feel for what is going
> on. Suppose you have a dish that is a perfect paraboloid, except for
> one little dent that's a little farther from the focus. Suppose the
> dent is 1/2 wavelength farther from the focus than the rest of the
> dish. The signal that reflects off of that dent will be 1/2
> wavelength late,
------------------------------
Message: 11
Date: Sat, 26 Jul 2008 13:17:30 +0200 (CEST)
From: "Rob Hardenberg PE1ITR" <rob(AT)itr-datanet.com>
Subject: [amsat-bb] DELFIC3 Transponder report
To: amsat-bb(AT)amsat.org
Message-ID:
<33680.62.194.134.114.1217071050.squirrel(AT)customer.itr-datanet.com>
Content-Type: text/plain;charset=iso-8859-1
Hi all,
Today I could make my first qso via the delfic3 transponder with good signals
around 10:53UTC:
- wkd ha2rd 57 signals
- hrd f5etm
- ssb signals where to weak at < 4 degrees el
- I could hear my cw downlink to <0.5 degrees el
Thanks to command team to switch the transponder on remotly from the amsat
weekend in surrey. At
the moment there is no full-turn of the transponder but that will soon happen.
73 Rob PE1ITR
http://www.pe1itr.com
------------------------------
Message: 12
Date: Sat, 26 Jul 2008 14:29:38 +0100
From: "Angus" <angus(AT)young5769.freeserve.co.uk>
Subject: [amsat-bb] Re crossed yagi question.
To: <amsat-bb(AT)amsat.org>
Message-ID: <EB616E898F7D421BA3EA1E4CA34D1B8E(AT)GusPC>
Content-Type: text/plain; charset="iso-8859-1"
OK now that I have a crossed yagi in the X format, I must say I am very
pleased with its performance.
Here is the question with the yagi in the X format, does it perform as well
when set with delay lines to horizontal polarity as a yagi with the same gain
beam width etc set in the horizontal polarity?
I ask this as I don't have a lot of test equipment and most of my results are
a 'by ear' equipment.
I just wonder if anyone (someone will have I am sure) has done any checking to
see what if any difference there is between X set to Horizontal and a normal
yagi set in horizontal?
Thanks for allowing me to ask what might be some very daft/odd questions hi
regards
Gus M0IKB
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------------------------------
Message: 13
Date: Sat, 26 Jul 2008 10:42:59 -0300
From: "Bruce Robertson" <ve9qrp(AT)gmail.com>
Subject: [amsat-bb] Delfi-N3xt
To: Amsat-Bb <amsat-bb(AT)amsat.org>
Message-ID:
<49657a760807260642x59dffdf8o37b734cedabddccc(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Gang:
Just watched the excellent presentation from the Delfi team, outlining
a new satellite using the 3-cube approach that they have successfully
implemented in the Delfi-C3 project. They are planning a high-baud
S-band downlink for burst data download and a space-weather
measurement experiment. Great stuff.
Once again, they want tangibly to 'give back' to the amateurs. They
mentioned an improved U/V transponder like the one in Delfi-C3, but
they'd also like to entertain new ideas from us. What do we think?
73, Bruce
VE9QRP
------------------------------
Message: 14
Date: Sat, 26 Jul 2008 09:46:40 -0400
From: "Mr Jeffrey L Ross" <radiooperator(AT)comcast.net>
Subject: [amsat-bb] go-32 techsat1b
To: "amsat" <amsat-bb(AT)amsat.org>
Message-ID: <001201c8ef26$098695f0$6401a8c0(AT)hamshackcomputer>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hi folks, going to try again this am pass. I feel there is nothing coming
from go-32 again but will give it another shot. I Have a good pass at 73
degrees over head. I Thought I would let everyone know that you can get a
whole page of data without moving the antenna or the doppler. This
information is good to know. I have done it before.
At least from this sat. The address to write techsat1b was no good but will
keep trying. (website) Looks like the last time they reached up to her was
2002. Hopefully not. Anyway wish me luck. USA pass is 1049 am.
kc8gkf
------------------------------
Message: 15
Date: Sat, 26 Jul 2008 10:06:39 -0400
From: "Mr Jeffrey L Ross" <radiooperator(AT)comcast.net>
Subject: [amsat-bb] go-32 techsat1b
To: "amsat" <amsat-bb(AT)amsat.org>
Message-ID: <001a01c8ef28$d4ec10b0$6401a8c0(AT)hamshackcomputer>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Hi folks. well did not capture anything but did get my sqelze to break and a
sound from it. I think something is wrong with go-32. will check back later.
kc8gkf
1049 am pass USA 73 Degrees max Michigan
------------------------------
Message: 16
Date: Sat, 26 Jul 2008 16:42:40 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: Re crossed yagi question.
To: "Angus" <angus(AT)young5769.freeserve.co.uk>, "AMSAT-BB"
<amsat-bb(AT)amsat.org>
Message-ID: <005501c8ef2d$dbb506e0$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: Saturday, July 26, 2008 3:29 PM
Subject: [amsat-bb] Re crossed yagi question.
> OK now that I have a crossed yagi in the X format, I must say I am very
pleased with its performance.
> Here is the question with the yagi in the X format, does it perform as
well when set with delay lines to horizontal polarity as a yagi with the
same gain beam width etc set in the horizontal polarity?
> I ask this as I don't have a lot of test equipment and most of my results
are a 'by ear' equipment.
> I just wonder if anyone (someone will have I am sure) has done any
checking to see what if any difference there is between X set to Horizontal
and a normal yagi set in horizontal?
> Thanks for allowing me to ask what might be some very daft/odd questions
hi
> regards
> Gus M0IKB
>
Hi Gus, M0IKB
If you want the switching polarization agility be happy with your crossed
yagi in the X format.
In theory your polarization switcher send 50% of power to the \ yagi and the
other 50 % to the other / yagi.
The components \ and / can be combined by the switcher to make a resultant
that can be horizontal or vertical but any polarization switcher has losses
due to relays and delay lines.
In particular to divide exactly the power 50% to the \ dipole and / dipole
is difficult and this can generate a resultant that is not exacly horizontal
or exactly vertical.
In conclusion if you feed 100% of your power to a single horizontal antenna
or to a single vertical one it is better but if you need the polarization
agility to get V-H-RHCP and LHCP there is no way to do different and a good
polarization switcher is mandatory.
For the theory on how a four polarity switch works read please the article
"Switching Four Polarizations on a 70 cm Crossed yagi" Part-1 publisched
in the AMSAT Journal March/April 2007 www.amsat.org
For building the switcher read Part-2 in the issue May/June 2007
73" de
i8CVS Domenico
------------------------------
Message: 17
Date: Sat, 26 Jul 2008 12:07:09 -0400
From: David - KG4ZLB/M?ZLB <m0zlb(AT)btinternet.com>
Subject: [amsat-bb] Re: Delfi-N3xt
To: Bruce Robertson <ve9qrp(AT)gmail.com>
Cc: Amsat-Bb <amsat-bb(AT)AMSAT.Org>
Message-ID: <488B4BAD.9030402(AT)btinternet.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Bruce,
It was a great presentation but I wonder how _*they*_ manage to fund the
launches (?)
73
David
KG4ZLB
Bruce Robertson wrote:
> Gang:
>
> Just watched the excellent presentation from the Delfi team, outlining
> a new satellite using the 3-cube approach that they have successfully
> implemented in the Delfi-C3 project. They are planning a high-baud
> S-band downlink for burst data download and a space-weather
> measurement experiment. Great stuff.
>
> Once again, they want tangibly to 'give back' to the amateurs. They
> mentioned an improved U/V transponder like the one in Delfi-C3, but
> they'd also like to entertain new ideas from us. What do we think?
>
>
> 73, Bruce
> VE9QRP
> _______________________________________________
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>
>
--
*David*
*KG4ZLB/M?ZLB*
*www.kg4zlb.com <http://www.kg4zlb.com/>*
*www.m?zlb.com <http://www.m0zlb.com/>*
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End of AMSAT-BB Digest, Vol 3, Issue 376
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