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CX2SA > SATDIG 28.04.10 20:07l 344 Lines 9699 Bytes #999 (0) @ WW
BID : AMSATBB5193
Read: GUEST
Subj: AMSAT-BB-digest V5 193
Path: IZ3LSV<IK2XDE<DB0RES<ON0AR<HS1LMV<CX2SA
Sent: 100428/1904Z @:CX2SA.LAV.URY.SA #:56336 [Minas] FBB7.00e $:AMSATBB5193
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: AO-51 L band requirements (Gould Smith)
2. Re: AO-51 L band requirements (i8cvs)
3. Galaxis Space Scanner ACU (Joe Leikhim)
4. Japanese Launch May 18 (Trevor .)
5. [Fwd: 2nd Birthday of COMPASS-1] (Compass1Cubesat)
6. AO-51 mode L/U (Luc Leblanc)
7. Re: Galaxis Space Scanner ACU (Luc Leblanc)
8. EMCOMM West (Mark Spencer)
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Message: 1
Date: Tue, 27 Apr 2010 15:40:43 -0400
From: "Gould Smith" <gouldsmi@xxxxxxxxx.xxx>
Subject: [amsat-bb] Re: AO-51 L band requirements
To: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <30295C25BC7047A09E1D9711FAAA500E@xxxxxxxxxxx>
Content-Type: text/plain; format=flowed; charset="utf-8";
reply-type=original
Hi Bob,
As noted in the book, Mike Seguin, N1JEZ did those measurements during the
first few months after launch. They proved to be pretty close as I remember.
Mike noted that he was able to hold the L band uplink with 50W EIRPc, after
he had fine tuned his antenna and carefully adjusted his Doppler to the
center of the capture window. Once people found the uplink frequency sweet
spot for their TX and used auto Doppler, things also improved.
We also tweaked the audio level into the trasmitter over time to improve the
transmit audio from the satellite.
But in year six, it is probably a good time to get some new measurements.
73,
Gould, WA4SXM
----- Original Message -----
From: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Tuesday, April 27, 2010 2:40 PM
Subject: [amsat-bb] AO-51 L band requirements
>
>
> Reading the AO-51 book by Gould where he discuses the L band requirements.
> For occasional contact 150 W EIRP is needed. For superior performance 1 Kw
> EIRP needed. Assuming I start out with 10W to a 16 turn helix 40 feet
> away. Guesstimating- 5-8 W at the antenna, helix gain 8-12db. Guestimated
> EIRP about 40W (worst case). Am I figuring this correct? If so then AO-51
> is performing better than what the book says. I am trying to "fine tune"
> what I have.
>
> Thanks 73 Bob W7LRD
>
> Seattle
> _______________________________________________
> 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: Tue, 27 Apr 2010 22:24:50 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
Subject: [amsat-bb] Re: AO-51 L band requirements
To: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>, "AMSAT-BB" <amsat-bb@xxxxx.xxx>
Message-ID: <004701cae647$b0bfb260$0201a8c0@xxx.xx>
Content-Type: text/plain; charset="utf-8"
----- Original Message -----
From: "Bob- W7LRD" <w7lrd@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Sent: Tuesday, April 27, 2010 8:40 PM
Subject: [amsat-bb] AO-51 L band requirements
>
>
> Reading the AO-51 book by Gould where he discuses the L band requirements.
> For occasional contact 150 W EIRP is needed. For superior performance 1 Kw
> EIRP needed. Assuming I start out with 10W to a 16 turn helix 40 feet
> away.Guesstimating- 5-8 W at the antenna, helix gain 8-12db. Guestimated
> EIRP about 40W (worst case). Am I figuring this correct? If so then AO-51
> is performing better than what the book says. I am trying to "fine tune"
> what I have.
>
> Thanks 73 Bob W7LRD
>
> Seattle
Hi Bob ,W7LRD
The gain of a 16 turn helix is much more than 8 - 10 dBi .Supposing that the
circunference of a turn = Lambda or one wavelenght = 23 cm and the pich
angle between turns is Alpha = 12.5 ? then the half-power beamwidth can be
calculated using the following formula from Kraus book "ANTENNAS"
Half-power beamwidth = 52? / SQR ( n x tan alpha ) where n= numbar of
turns and so for 16 turns helix we have:
Half power beamwidth = 52? / SQR ( 16 x tan 12.5? ) = 27.6?
An antenna having a lobe large as 27.6? at the -3dB points in 1268 MHz is
corresponding to a parabolic dish with 70 cm in diameter and has a gain of
16 dBi corresponding to 40 time in power ratio.
If the power reaching your 16 turns helix antenna is only 5 watt then your
EIRP=5 x 40=200 watt and if the power is 8 watt your EIRP= 8x40=320 watt
It seems that the book by Gould is correct.
73" de
i8CVS Domenico
------------------------------
Message: 3
Date: Tue, 27 Apr 2010 23:51:00 -0400
From: Joe Leikhim <rhyolite@xxxxxxxx.xxx>
Subject: [amsat-bb] Galaxis Space Scanner ACU
To: amsat-bb@xxxxx.xxx
Message-ID: <4BD7B0A4.8000200@xxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I have found a number of the model Galaxis Space Scanner ACU Labeled as
being made by FutureTrak Intl, and having Lockheed-Martin manufacturer
labels. These were apparently made for tracking DBS satellites from
yachts and RV's.
I saw a post a while back about a website on using these for Ham Sats.
Does such information still exist?
--
Joe Leikhim
Leikhim and Associates
Communications Consultants
Oviedo, Florida
www.Leikhim.com
JLeikhim@xxxxxxx.xxx
407-982-0446
------------------------------
Message: 4
Date: Wed, 28 Apr 2010 12:34:53 +0000 (GMT)
From: "Trevor ." <m5aka@xxxxx.xx.xx>
Subject: [amsat-bb] Japanese Launch May 18
To: amsat-bb@xxxxx.xxx
Message-ID: <120527.29823.qm@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
Story about Ikaros which launches May 18 along with the Amateur Radio
satellites UNITEC-1, Negai and WASEDA-SAT2
http://www.space-travel.com/reports/Japan_to_launch_space_yacht_propelled_by_s
olar_particles_999.html
73 Trevor M5AKA
Daily Amateur Radio Email/RSS News: http://www.southgatearc.org/
Email Your News To: editor at southgatearc.org
Or Upload Using Form At: http://www.southgatearc.org/news/your_news_1.htm
----
------------------------------
Message: 5
Date: Wed, 28 Apr 2010 13:57:27 +0200
From: Compass1Cubesat <compass1cubesat@xxxxxxxxxx.xxx>
Subject: [amsat-bb] [Fwd: 2nd Birthday of COMPASS-1]
To: Ulli Hacker <DK2BJ@xxx.xxx>, Norbert Raussen <raussen@xxxxxx.xx>,
Frans van Venrooij <f.v.venrooij@xxxxxx.xx>, Andreas Bilsing
<dl2lux@xxx.xx>, amsat-bb@xxxxx.xxx
Message-ID: <4BD822A7.8050701@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
------------------------------
Message: 6
Date: Tue, 27 Apr 2010 22:06:45 -0400
From: Luc Leblanc <lucleblanc6@xxxxxxxxx.xx>
Subject: [amsat-bb] AO-51 mode L/U
To: amsat-bb@xxxxx.xxx
Message-ID: <4BD75FF5.5289.65476AF@xxxxxxxxxxx.xxxxxxxxx.xx>
Content-Type: text/plain; charset=US-ASCII
Since the new L/U schedule very few operators has been heard on this mode.
The first day N8MH give his call sign and about 4 or 5 users are
operating when i have the sat in view.
It seems the uplink is much more critical than the past L band uplink
sessions. it look like the receiver bandwidth was reduce making
frequency adjustment more critical. I know the audio level is reduce to save
energy but it could explain why many seems to find it is
harder to get on the right uplink frequency?
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
DSTAR urcall VE2DWE
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 7
Date: Wed, 28 Apr 2010 03:48:52 -0400
From: Luc Leblanc <lucleblanc6@xxxxxxxxx.xx>
Subject: [amsat-bb] Re: Galaxis Space Scanner ACU
To: amsat-bb@xxxxx.xxx
Message-ID: <4BD7B024.30726.D1CDF@xxxxxxxxxxx.xxxxxxxxx.xx>
Content-Type: text/plain; charset=US-ASCII
On 27 Apr 2010 at 23:51, Joe Leikhim wrote:
Date sent: Tue, 27 Apr 2010 23:51:00 -0400
From: Joe Leikhim <rhyolite@xxxxxxxx.xxx>
Subject: [amsat-bb] Galaxis Space Scanner ACU
To: amsat-bb@xxxxx.xxx
> I have found a number of the model Galaxis Space Scanner ACU Labeled as
> being made by FutureTrak Intl, and having Lockheed-Martin manufacturer
> labels. These were apparently made for tracking DBS satellites from
> yachts and RV's.
>
> I saw a post a while back about a website on using these for Ham Sats.
> Does such information still exist?
>
> --
> Joe Leikhim
>
> Leikhim and Associates
> Communications Consultants
> Oviedo, Florida
>
> www.Leikhim.com
>
> JLeikhim@xxxxxxx.xxx
>
> 407-982-0446
>
Here is what i found:
http://www.bootkeyharbor.com/ProductInfo/BoatManuals/FutureTrakSpaceScannerSat
TVUserManual.PDF
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
DSTAR urcall VE2DWE
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 8
Date: Wed, 28 Apr 2010 10:42:55 -0700
From: "Mark Spencer" <mspencer@xxxxxx.xxx>
Subject: [amsat-bb] EMCOMM West
To: <amsat-bb@xxxxx.xxx>
Message-ID:
<20100428174309.65D6630EE893@xxxxxxxxxxx.x.xxxxxxxxxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
There will be a special event station set up and operating in Reno, NV this
weekend for EMCOMM West. The station W7ECW will be on the air for as many
satellites as can be accessed. If you need DM09 or just want to say HI to
the audience of the demonstration, please give us a shout.
Mark Spencer, WA8SME
Education and Technology Program Coordinator
ARRL, the national association for Amateur RadioT
mspencer@xxxx.xxx
www.arrl.org/education-technology-program
www.arrl.org/teachers-institute-on-wireless-technology
530-495-9150
------------------------------
_______________________________________________
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 5, Issue 193
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