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CX2SA > SATDIG 03.09.08 17:04l 941 Lines 30427 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Icom UX-910 Module (AC7YY - Kim)
2. Information request (Jim Sanford)
3. Re: Information request (John Franke)
4. Re: Information Request (Rm2642(AT)aol.com)
5. sun noise and other natural noise sources (Michael Heim)
6. Re: Information request (Jim Sanford)
7. Worked FO-29! (John Marranca, Jr)
8. Re: Worked FO-29! (Andrew Glasbrenner)
9. Re: How best to park your satellite antennas (Greg D.)
10. LEO DX RS-6 and RS-8 (Andy MacAllister)
11. Re: How best to park your satellite antennas (Edward Cole)
12. Re: LEO DX RS-6 and RS-8 (John W Lee)
13. Re: LEO DX RS-6 and RS-8 (Andy MacAllister)
14. Re: LEO DX RS-6 and RS-8 (BEA)
15. Re: How best to park your satellite antennas (i8cvs)
16. Re: How best to park your satellite antennas (Luc Leblanc)
----------------------------------------------------------------------
Message: 1
Date: Tue, 02 Sep 2008 12:52:07 -0700
From: AC7YY - Kim <ac7yy(AT)comcast.net>
Subject: [amsat-bb] Icom UX-910 Module
To: amsat-bb <amsat-bb(AT)amsat.org>
Message-ID: <1220385127.6355.45.camel(AT)kim-desktop>
Content-Type: text/plain
I purchased the 1.2Gb UX-910 module at Seapac. I have not installed it
and I am now wanting another radio. I paid about $600 for it.
Will sell it for $450. If interested contact me directly at:
ac7yy(AT)amsat.org
kim - ac7yy
------------------------------
Message: 2
Date: Tue, 02 Sep 2008 18:35:59 -0400
From: Jim Sanford <wb4gcs(AT)amsat.org>
Subject: [amsat-bb] Information request
To: "'Amsat - BBs'" <amsat-bb(AT)amsat.org>
Message-ID: <48BDBFCF.5070702(AT)amsat.org>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
All:
4 or 6 years ago, there was an article in the Journal regarding a 2.4
GHz antenna tuning aid. As I recall, it was basically a return loss
bridge, with an included VCO, and a DC or meter output. I'd like to
revisit that article, but have not yet found it in a quick scan of
tables of contents from my collection.
Does anyone remember when that article was published? I'd appreciate a
pointer; probably have the issue, just can't figure out which one.
Thanks & 73,
Jim
wb4gcs(AT)amsat.org
------------------------------
Message: 3
Date: Tue, 2 Sep 2008 19:02:27 -0400
From: "John Franke" <jmfranke(AT)cox.net>
Subject: [amsat-bb] Re: Information request
To: "Jim Sanford" <wb4gcs(AT)amsat.org>, "'Amsat - BBs'"
<amsat-bb(AT)amsat.org>
Message-ID: <0E387DE5C0F941E5ADE5439E7D13E484(AT)youre7075dc078>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Try September/October 2000 pages 13-19, "Putting Together a L/S Antenna
System for thr Phase 3D Satellite by Jim Koehler, VE5FP and Eric Rawson,
KN6KC. They discribe two RF bridges with on board VCOs, one for 1.2 GHz and
one for 2.4 GHz.
John WA4WDL
----- Original Message -----
From: "Jim Sanford" <wb4gcs(AT)amsat.org>
To: "'Amsat - BBs'" <amsat-bb(AT)amsat.org>
Sent: Tuesday, September 02, 2008 6:35 PM
Subject: [amsat-bb] Information request
> All:
> 4 or 6 years ago, there was an article in the Journal regarding a 2.4
> GHz antenna tuning aid. As I recall, it was basically a return loss
> bridge, with an included VCO, and a DC or meter output. I'd like to
> revisit that article, but have not yet found it in a quick scan of
> tables of contents from my collection.
>
> Does anyone remember when that article was published? I'd appreciate a
> pointer; probably have the issue, just can't figure out which one.
>
> Thanks & 73,
> Jim
> wb4gcs(AT)amsat.org
> _______________________________________________
> 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: 4
Date: Tue, 2 Sep 2008 19:33:53 EDT
From: Rm2642(AT)aol.com
Subject: [amsat-bb] Re: Information Request
To: amsat-bb(AT)amsat.org
Message-ID: <c09.4488482b.35ef2761(AT)aol.com>
Content-Type: text/plain; charset="US-ASCII"
Hi Jim:
This S band measurement technique I thought was interesting. It's a broad
band directional coupler, can be used for L band too.
Doesn't have a VCO but gives a good visual indication of return loss.
_http://www.qsl.net/n9zia/24swr/index.html_
(http://www.qsl.net/n9zia/24swr/index.html)
73,
Ron
n6paa
**************It's only a deal if it's where you want to go. Find your travel
deal here.
(http://information.travel.aol.com/deals?ncid=aoltrv00050000000047)
------------------------------
Message: 5
Date: Tue, 2 Sep 2008 17:06:15 -0700 (PDT)
From: Michael Heim <kd0ar(AT)sbcglobal.net>
Subject: [amsat-bb] sun noise and other natural noise sources
To: AMSAT-BB(AT)amsat.org
Message-ID: <202643.97363.qm(AT)web81506.mail.mud.yahoo.com>
Content-Type: text/plain; charset=us-ascii
I am working on an S-band receive setup. I currently operate X band
terrestrial, and used sun noise as a test of my receive equipment there. It
is quite weak on 10 GHz. Noise from the earth (aimed at the ground) is many
times stronger. Aiming at trees, buildings, etc produce substantial noise on
10 GHz. The question I have is... Can I use the same techniques on 2.4 GHz?
Of course antenna gain is lower, but noise figure should be fairly close - 1dB
or so....
I have 2 units for 2.4 I'm testing. one has an integral yagi antenna,
supposedly about 16dB gain. The other has an N connector, of which I have not
designed an antenna for it yet.
So, the question is... is sun noise stronger, weaker on 2.4 than on 10 ghz?
If equipment is functioning properly should I be able to detect the sun? I
actually didnt think about trying to hear a tree on it, but they should also
be noise sources on that band as well.
Michael Heim
ARS KD0AR
------------------------------
Message: 6
Date: Tue, 02 Sep 2008 20:53:27 -0400
From: Jim Sanford <wb4gcs(AT)amsat.org>
Subject: [amsat-bb] Re: Information request
To: John Franke <jmfranke(AT)cox.net>
Cc: 'Amsat - BBs' <amsat-bb(AT)amsat.org>
Message-ID: <48BDE007.5010804(AT)amsat.org>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
That's it -- thanks!!
73,
Jim
wb4gcs(AT)amsat.org
John Franke wrote:
> Try September/October 2000 pages 13-19, "Putting Together a L/S
> Antenna System for thr Phase 3D Satellite by Jim Koehler, VE5FP and
> Eric Rawson, KN6KC. They discribe two RF bridges with on board VCOs,
> one for 1.2 GHz and one for 2.4 GHz.
>
> John WA4WDL
>
> ----- Original Message ----- From: "Jim Sanford" <wb4gcs(AT)amsat.org>
> To: "'Amsat - BBs'" <amsat-bb(AT)amsat.org>
> Sent: Tuesday, September 02, 2008 6:35 PM
> Subject: [amsat-bb] Information request
>
>
>> All:
>> 4 or 6 years ago, there was an article in the Journal regarding a 2.4
>> GHz antenna tuning aid. As I recall, it was basically a return loss
>> bridge, with an included VCO, and a DC or meter output. I'd like to
>> revisit that article, but have not yet found it in a quick scan of
>> tables of contents from my collection.
>>
>> Does anyone remember when that article was published? I'd appreciate a
>> pointer; probably have the issue, just can't figure out which one.
>>
>> Thanks & 73,
>> Jim
>> wb4gcs(AT)amsat.org
>> _______________________________________________
>> 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: 7
Date: Tue, 2 Sep 2008 21:31:01 -0400
From: "John Marranca, Jr" <KB2HSH(AT)amsat.org>
Subject: [amsat-bb] Worked FO-29!
To: amsat-bb(AT)amsat.org
Message-ID:
<8edcdb130809021831x31171fd2xffb9cb25f57ec081(AT)mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Greetings all.....
Just wanted to brag a bit to mention that I worked W9VNE on FO-29 during the
Labor Day weekend. I was transmitting CW, and heard Jim/W9VNE returning to
me in SSB. TNX Jim.
For what it's worth, FO-29 can be heard at less than 5 degrees. What a
GREAT SIGNAL!
Can't wait for my CT62 cable!
73 de KB2HSH
--
_______________________________
John Marranca, Jr
PBX Technician/Shop Steward CWA Local 1122
BN Systems, Inc
Orchard Park, NY
(716)972-2006
------------------------------
Message: 8
Date: Tue, 2 Sep 2008 21:50:42 -0400
From: "Andrew Glasbrenner" <glasbrenner(AT)mindspring.com>
Subject: [amsat-bb] Re: Worked FO-29!
To: "John Marranca, Jr" <KB2HSH(AT)amsat.org>, <amsat-bb(AT)amsat.org>
Message-ID: <920863CC3764466DB9E31F43F49C5065(AT)Andrewlaptop>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Congratulations! What sort of setup were you using?
73, Drew KO4MA
----- Original Message -----
From: "John Marranca, Jr" <KB2HSH(AT)amsat.org>
To: <amsat-bb(AT)amsat.org>
Sent: Tuesday, September 02, 2008 9:31 PM
Subject: [amsat-bb] Worked FO-29!
> Greetings all.....
>
> Just wanted to brag a bit to mention that I worked W9VNE on FO-29 during
> the
> Labor Day weekend. I was transmitting CW, and heard Jim/W9VNE returning
> to
> me in SSB. TNX Jim.
>
> For what it's worth, FO-29 can be heard at less than 5 degrees. What a
> GREAT SIGNAL!
>
> Can't wait for my CT62 cable!
>
>
> 73 de KB2HSH
>
> --
> _______________________________
>
>
> John Marranca, Jr
> PBX Technician/Shop Steward CWA Local 1122
> BN Systems, Inc
> Orchard Park, NY
> (716)972-2006
> _______________________________________________
> 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: 9
Date: Tue, 2 Sep 2008 19:59:06 -0700
From: "Greg D." <ko6th_greg(AT)hotmail.com>
Subject: [amsat-bb] Re: How best to park your satellite antennas
To: Graham Shirville <g.shirville(AT)btinternet.com>,
<amsat-bb(AT)amsat.org>
Message-ID: <BLU133-W199405CD362B13C4D119FCA95E0(AT)phx.gbl>
Content-Type: text/plain; charset="iso-8859-1"
Looking at the picture, Domenico's suggestion of going vertical and sideways
is still going to put all of the antennas broadside to the wind. Instead, how
about just aiming them at wind direction (either at it or directly away),
horizontally? That way the only wind load would be from the antenna's end-on
area, instead of the whole length. This is what I do, and it seems to have
worked. If I go vertical, my worry is that the height of the antenna gets to
be a good bit longer than the width of the tripod base, and I'm concerned the
whole thing will tip over.
But, Domenico does have an interesting idea about aiming at 90-degrees from
the wind, but horizontal. That would put the dish edge-on to the wind, at the
expense of putting the beams sideways to the wind. Given the modest size of
my dish, I would expect that it's not going to be better that way.
How does one calculate such a thing, given that I don't know the
manufacturer's wind loading of anything, and don't care to earn a degree in
fluid dynamics? Any very simplified back-of-the-envelope way to get a rough
idea?
My picture at: http://home.wavecable.com/~ko6th/IMG_0141b6.jpg
Greg KO6TH
----------------------------------------
> From: g.shirville(AT)btinternet.com
> To: amsat-bb(AT)amsat.org
> Date: Tue, 2 Sep 2008 18:26:20 +0100
> Subject: [amsat-bb] Re: How best to park your satellite antennas
>
> Thanks for all the comments...and apologies for the link error ...it should
> have read 193.51.107.114
>
> 73
>
> Graham
>
>
> > If you look at 193.51.07.114 you can see the sort of array that I am
> talking about!
>>
>> Many thanks
>>
>> Graham
>> G3VZV
>> _______________________________________________
>> 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
>
> _______________________________________________
> 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
_________________________________________________________________
Get ideas on sharing photos from people like you. Find new ways to share.
http://www.windowslive.com/explore/photogallery/posts?ocid=TXT_TAGLM_WL_Photo_
Gallery_082008
------------------------------
Message: 10
Date: Tue, 2 Sep 2008 22:22:57 -0500
From: "Andy MacAllister" <w5acm(AT)swbell.net>
Subject: [amsat-bb] LEO DX RS-6 and RS-8
To: "'AMSAT BBS'" <amsat-bb(AT)amsat.org>
Message-ID: <000501c90d74$5d1feab0$6c00a8c0(AT)w5acmathlon>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
I have been looking through my QSO info on and off, for a while now, digging
for my QSO to Germany via AO-7B, in the early 1980's. It hasn't surfaced
yet, but I did run across two QSL cards from DC9ZP for contacts from my
previous QTH in Pearland, Texas to Sorup, Germany via RS-6 and RS-8 in 1982.
Manfred calculated the distance to be 8262.23 km. My calculation is more
like 8225 km.
Has anyone been working up DX lists for RS-6 and RS-8?
73 de Andy W5ACM
------------------------------
Message: 11
Date: Tue, 02 Sep 2008 19:42:59 -0800
From: Edward Cole <kl7uw(AT)acsalaska.net>
Subject: [amsat-bb] Re: How best to park your satellite antennas
To: "i8cvs" <domenico.i8cvs(AT)tin.it>, "Graham Shirville"
<g.shirville(AT)btinternet.com>, "AMSAT-BB" <amsat-bb(AT)amsat.org>
Message-ID: <200809030343.m833h0g8041418(AT)iris.acsalaska.net>
Content-Type: text/plain; charset="us-ascii"; format=flowed
At 09:16 AM 9/2/2008, i8cvs wrote:
>----- Original Message -----
>From: "Graham Shirville" <g.shirville(AT)btinternet.com>
>To: <amsat-bb(AT)amsat.org>
>Sent: Tuesday, September 02, 2008 6:35 PM
>Subject: [amsat-bb] How best to park your satellite antennas
>
> > Hi all,
> >
> > I cannot remember this question being discussed before!
> >
> > If you have a nice array of VHF and UHF antennas - 2 stacked X 8 foot
>long yagis one ach band plus a 2 foot S band dish, is it best from wind
>loading and other reasons to park it:
> > vertically pointing straight up (the dish has a hole at the bottom)
> > pointing to the horizon towards the prevailing wind
> > somewhere else?
> >
> > I know that at SSTL in Guildford they are usually parked pointing straight
>up but I have never been able to find anyone with a really good explanation
>for doing so.
> >
> > If you look at 193.51.07.114 you can see the sort of array that I am
>talking about!
> >
> > Many thanks
> >
> > Graham
> > G3VZV
>
>Hi Graham, G3VZV
>
>Pointing straight up with the main supporting boom in direction of the
>dominant wind is the best because the dish will offer the minimum surface
>to the wind while both yagi's are aligned in a way to be seen by the wind as
>about a single antenna.
>
>The above is my experience with less damages into the windy gulf of Naples
>
>73" de
>
>i8CVS Domenico
Generally, large radio astronomy or space tracking dishes are parked
at zenith because this presents the smallest area exposure to
winds. Also, the dish load is balanced on its pedestal. For a
satellite array the long yagis present as much wind area as a small
2-foot dish. One could point the array directly into the wind but
this would present the full area of the dish to wind loading. If the
array is pointed 90-degrees from the wind direction and pointed to
the zenith, wind area would be minimized.
For my new 16-foot eme dish there is another consideration (living in
Alaska). That is snow loading. A dish pointed straight up will fill
with snow and rain definitely overloading it. The best stow position
is on the horizon and pointed 90-degrees to the prevailing
wind. Large dishes should have tie-down wires for further
stablization in high winds.
So it varies with the situation and type of antennas. The idea is to
minimize wind area.
*****************************************************
73, Ed - KL7UW BP40iq, 6m - 3cm
144-EME: FT-847, mgf-1801, 4x-xp20, 185w
http://www.kl7uw.com AK VHF-Up Group
NA Rep. for DUBUS: dubususa(AT)hotmail.com
*****************************************************
------------------------------
Message: 12
Date: Tue, 2 Sep 2008 20:10:58 -0800
From: John W Lee <k6yk(AT)juno.com>
Subject: [amsat-bb] Re: LEO DX RS-6 and RS-8
To: w5acm(AT)swbell.net
Cc: amsat-bb(AT)amsat.org
Message-ID: <20080902.204350.4768.4.k6yk(AT)juno.com>
Content-Type: text/plain; charset=us-ascii
I haven't checked for distance, but
I did work a JA on one of those RS's and a couple of
UAO's.
73
JOhn K6YK
On Tue, 2 Sep 2008 22:22:57 -0500 "Andy MacAllister" <w5acm(AT)swbell.net>
writes:
> I have been looking through my QSO info on and off, for a while now,
> digging
> for my QSO to Germany via AO-7B, in the early 1980's. It hasn't
> surfaced
> yet, but I did run across two QSL cards from DC9ZP for contacts from
> my
> previous QTH in Pearland, Texas to Sorup, Germany via RS-6 and RS-8
> in 1982.
> Manfred calculated the distance to be 8262.23 km. My calculation is
> more
> like 8225 km.
>
> Has anyone been working up DX lists for RS-6 and RS-8?
>
> 73 de Andy W5ACM
>
>
> _______________________________________________
> 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
>
>
____________________________________________________________
Click for free home mortgage rates from top companies.
http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m36kGt4ESfTNBvHT9jm7jLAfYJ9
oyFfo4Wbb2OjQspSKfER/
------------------------------
Message: 13
Date: Wed, 3 Sep 2008 00:13:27 -0500
From: "Andy MacAllister" <w5acm(AT)swbell.net>
Subject: [amsat-bb] Re: LEO DX RS-6 and RS-8
To: <amsat-bb(AT)amsat.org>
Message-ID: <000701c90d83$ccfded00$6c00a8c0(AT)w5acmathlon>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
The UA0's were just a bit beyond my horizon. The JA's were only a dream or
required Mode K with HF skip!
Andy
----- Original Message -----
From: "John W Lee" <k6yk(AT)juno.com>
To: <w5acm(AT)swbell.net>
Cc: <amsat-bb(AT)amsat.org>
Sent: Tuesday, September 02, 2008 11:10 PM
Subject: Re: [amsat-bb] LEO DX RS-6 and RS-8
>I haven't checked for distance, but
> I did work a JA on one of those RS's and a couple of
> UAO's.
>
> 73
> JOhn K6YK
>
>
> On Tue, 2 Sep 2008 22:22:57 -0500 "Andy MacAllister" <w5acm(AT)swbell.net>
> writes:
>> I have been looking through my QSO info on and off, for a while now,
>> digging
>> for my QSO to Germany via AO-7B, in the early 1980's. It hasn't
>> surfaced
>> yet, but I did run across two QSL cards from DC9ZP for contacts from
>> my
>> previous QTH in Pearland, Texas to Sorup, Germany via RS-6 and RS-8
>> in 1982.
>> Manfred calculated the distance to be 8262.23 km. My calculation is
>> more
>> like 8225 km.
>>
>> Has anyone been working up DX lists for RS-6 and RS-8?
>>
>> 73 de Andy W5ACM
>>
>>
>> _______________________________________________
>> 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
>>
>>
>
> ____________________________________________________________
> Compete with the big boys. Click here to find products to benefit your
> business.
>
http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m7tDkbW2Ma372eU1hGi6uwr5QZh
oWx1nfVss9mCe5CGzNB1/
>
------------------------------
Message: 14
Date: Wed, 3 Sep 2008 08:37:26 -0300
From: "BEA" <impi(AT)nbnet.nb.ca>
Subject: [amsat-bb] Re: LEO DX RS-6 and RS-8
To: "Andy MacAllister" <w5acm(AT)swbell.net>, <amsat-bb(AT)amsat.org>
Message-ID: <1BD3A6F2518C44F680E588110D288FEA(AT)JDSYSTEM>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
Please remove my Dad from your forward list. He is terminally ill.
Thanks, Jim Dunfield(son)
----- Original Message -----
From: "Andy MacAllister" <w5acm(AT)swbell.net>
To: <amsat-bb(AT)amsat.org>
Sent: Wednesday, September 03, 2008 2:13 AM
Subject: [amsat-bb] Re: LEO DX RS-6 and RS-8
> The UA0's were just a bit beyond my horizon. The JA's were only a dream or
> required Mode K with HF skip!
> Andy
>
> ----- Original Message -----
> From: "John W Lee" <k6yk(AT)juno.com>
> To: <w5acm(AT)swbell.net>
> Cc: <amsat-bb(AT)amsat.org>
> Sent: Tuesday, September 02, 2008 11:10 PM
> Subject: Re: [amsat-bb] LEO DX RS-6 and RS-8
>
>
>>I haven't checked for distance, but
>> I did work a JA on one of those RS's and a couple of
>> UAO's.
>>
>> 73
>> JOhn K6YK
>>
>>
>> On Tue, 2 Sep 2008 22:22:57 -0500 "Andy MacAllister" <w5acm(AT)swbell.net>
>> writes:
>>> I have been looking through my QSO info on and off, for a while now,
>>> digging
>>> for my QSO to Germany via AO-7B, in the early 1980's. It hasn't
>>> surfaced
>>> yet, but I did run across two QSL cards from DC9ZP for contacts from
>>> my
>>> previous QTH in Pearland, Texas to Sorup, Germany via RS-6 and RS-8
>>> in 1982.
>>> Manfred calculated the distance to be 8262.23 km. My calculation is
>>> more
>>> like 8225 km.
>>>
>>> Has anyone been working up DX lists for RS-6 and RS-8?
>>>
>>> 73 de Andy W5ACM
>>>
>>>
>>> _______________________________________________
>>> 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
>>>
>>>
>>
>> ____________________________________________________________
>> Compete with the big boys. Click here to find products to benefit your
>> business.
>>
http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3m7tDkbW2Ma372eU1hGi6uwr5QZh
oWx1nfVss9mCe5CGzNB1/
>>
>
>
> _______________________________________________
> 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: 15
Date: Wed, 3 Sep 2008 14:16:33 +0200
From: "i8cvs" <domenico.i8cvs(AT)tin.it>
Subject: [amsat-bb] Re: How best to park your satellite antennas
To: "Graham Shirville" <g.shirville(AT)btinternet.com>, "AMSAT-BB"
<amsat-bb(AT)amsat.org>, "Edward Cole" <kl7uw(AT)acsalaska.net>, "Greg
D."
<ko6th_greg(AT)hotmail.com>
Message-ID: <007c01c90dbe$e7e40ec0$0201a8c0(AT)tin.it>
Content-Type: text/plain; charset="iso-8859-1"
----- Original Message -----
From: "Edward Cole" <kl7uw(AT)acsalaska.net>
To: "i8cvs" <domenico.i8cvs(AT)tin.it>; "Graham Shirville"
<g.shirville(AT)btinternet.com>; "AMSAT-BB" <amsat-bb(AT)amsat.org>
Sent: Wednesday, September 03, 2008 5:42 AM
Subject: Re: [amsat-bb] Re: How best to park your satellite antennas
> At 09:16 AM 9/2/2008, i8cvs wrote:
> >----- Original Message -----
> >From: "Graham Shirville" <g.shirville(AT)btinternet.com>
> >To: <amsat-bb(AT)amsat.org>
> >Sent: Tuesday, September 02, 2008 6:35 PM
> >Subject: [amsat-bb] How best to park your satellite antennas
> >
> > > Hi all,
> > >
> > > I cannot remember this question being discussed before!
> > >
> > > If you have a nice array of VHF and UHF antennas - 2 stacked X 8 foot
> > > long yagis one ach band plus a 2 foot S band dish, is it best from
> > > wind loading and other reasons to park it:
> > > vertically pointing straight up (the dish has a hole at the bottom)
> > > pointing to the horizon towards the prevailing wind
> > > somewhere else?
> > >
> > > I know that at SSTL in Guildford they are usually parked pointing
> > > straight up but I have never been able to find anyone with a really
> > > good explanation for doing so.
> > >
> > > If you look at 193.51.07.114 you can see the sort of array that I am
> > > talking about!
> > >
> > > Many thanks
> > >
> > > Graham
> > > G3VZV
> >
> >Hi Graham, G3VZV
> >
> >Pointing straight up with the main supporting boom in direction of the
> >dominant wind is the best because the dish will offer the minimum surface
> >to the wind while both yagi's are aligned in a way to be seen by the wind
> >as about a single antenna.
> >
> >The above is my experience with less damages into the windy gulf of
> > Naples
> >
> >73" de
> >
> >i8CVS Domenico
>
> Generally, large radio astronomy or space tracking dishes are parked
> at zenith because this presents the smallest area exposure to
> winds. Also, the dish load is balanced on its pedestal. For a
> satellite array the long yagis present as much wind area as a small
> 2-foot dish. One could point the array directly into the wind but
> this would present the full area of the dish to wind loading. If the
> array is pointed 90-degrees from the wind direction and pointed to
> the zenith, wind area would be minimized.
>
> For my new 16-foot eme dish there is another consideration (living in
> Alaska). That is snow loading. A dish pointed straight up will fill
> with snow and rain definitely overloading it. The best stow position
> is on the horizon and pointed 90-degrees to the prevailing
> wind. Large dishes should have tie-down wires for further
> stablization in high winds.
>
> So it varies with the situation and type of antennas. The idea is to
> minimize wind area.
>
> 73, Ed - KL7UW
Hi Ed, KL7UW
I am happy that you agree with me so please read the following.
A flat reflector with diameter D = 1.128 meters has a surface
S = 1 square meter
At a wind speed of 120 Km/h with the wind perpendicular to it
the force applied to the mounting frame is 70 Kg (kilograms)
If the reflector is a deep dish the above force must be multiplied
by K=1.6 and it becames 112 Kg / square meters
If a wind at 120 Km/h is applied perpendicular to standard
antennas with a net total metallic surface of 1 square meter
K= 1.4 and the force applied to the mounting frame becames
98 Kg / square meters
With Passive Reflectors and Antennas with flat radome K=1
and for antennas with aerodynamic Radome K= 0.8
It follow that the force applied to the mounting frame of a deep
dish with D = 60 cm when pointed directly into a wind direction
at 120/Km/h is about 31 Kg
Consequently pointing straight up with the main supporting boom
in direction of the dominant wind as I suggested that is the same that
you suggested using different words:
> If the array is pointed 90-degrees from the wind direction and
> pointed to the zenith, wind area would be minimized.
it seems to be the best parking position because the dish will offer
the minimum surface to the wind while both yagi's are aligned in a way
to be seen by the wind as about a single antenna.
In addition the wind will see the main supporting boom as a single point
wich surface is only the small diameter of the pipe.
In the above conditions the torque applied by the wind to the Elevation
rotator is the minimum possible and the same for the Azimutal rotator.
Infact if you point the antennas stright up at 90 degrees elevation and
90 degrees from the wind direction if you disconnect the mechanical
joint between the azimuthal rotator and the mast you will see that under
wind conditions the antenna will search the minimum load against
the wind positioning itself as naturally did a flag or as suggested by you
Ed and by my self in the above messages.
73" de
i8CVS Domenico
------------------------------
Message: 16
Date: Wed, 03 Sep 2008 06:14:16 -0400
From: Luc Leblanc <lucleblanc6(AT)videotron.ca>
Subject: [amsat-bb] Re: How best to park your satellite antennas
To: amsat-bb(AT)AMSAT.Org
Message-ID: <48BE2B38.13559.30BF3F(AT)lucleblanc6.videotron.ca>
Content-Type: text/plain; charset=US-ASCII
On 2 Sep 2008 at 19:16, i8cvs wrote:
> ----- Original Message -----
> From: "Graham Shirville" <g.shirville(AT)btinternet.com>
> To: <amsat-bb(AT)amsat.org>
> Sent: Tuesday, September 02, 2008 6:35 PM
> Subject: [amsat-bb] How best to park your satellite antennas
>
> > Hi all,
> >
> > I cannot remember this question being discussed before!
> >
> > If you have a nice array of VHF and UHF antennas - 2 stacked X 8 foot
> long yagis one ach band plus a 2 foot S band dish, is it best from wind
> loading and other reasons to park it:
> > vertically pointing straight up (the dish has a hole at the bottom)
> > pointing to the horizon towards the prevailing wind
> > somewhere else?
> >
> > I know that at SSTL in Guildford they are usually parked pointing straight
> up but I have never been able to find anyone with a really good explanation
> for doing so.
> >
> > If you look at 193.51.07.114 you can see the sort of array that I am
> talking about!
> >
> > Many thanks
> >
> > Graham
> > G3VZV
>
> Hi Graham, G3VZV
>
> Pointing straight up with the main supporting boom in direction of the
> dominant wind is the best because the dish will offer the minimum surface
> to the wind while both yagi's are aligned in a way to be seen by the wind as
> about a single antenna.
>
> The above is my experience with less damages into the windy gulf of Naples
>
> 73" de
>
> i8CVS Domenico
>
Hi Domenico and Graham
Under your latitude it's probably the best way to park a dish but if you lived
at an higher latitude things can be quite different...
Look at the first 3 pictures on my web page www.qsl.net/ve2dwe
You will understand why radome are built for. and a bit pricey for an amateur
stand point.
This event happens in December first 2006 one of numerous mother nature bad
effect but we don't have hurricane here and no palm trees...
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
WAC BASIC CW PHONE SATELLITE
------------------------------
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