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CX2SA > SATDIG 29.07.14 14:04l 237 Lines 6888 Bytes #999 (0) @ WW
BID : AMSATBB9260
Read: GUEST
Subj: AMSAT-BB-digest V9 260
Path: IW8PGT<IZ3LSV<IK2XDE<DB0RES<DB0ANF<CX2SA
Sent: 140729/1201Z @:CX2SA.SAL.URY.SOAM #:8711 [Salto] FBB7.00e $:AMSATBB9260
From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. Re: Digital Satellites Question (Robert Bruninga)
2. LituanicaSAT-1 (LO-78) Decayed (Paul Stoetzer)
3. Cape-2 Voice Repeater (Roland Zurmely)
4. AMSAT-UK Colloquium Pictures (M5AKA)
5. Enhanced FUNcube-1 Dashboard App now available (M5AKA)
6. test (Nick Pugh K5QXJ)
7. Yaesu G-5500 grounding question (Lizeth Norman)
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Message: 1
Date: Mon, 28 Jul 2014 10:11:23 -0400
From: Robert Bruninga <bruninga@xxxx.xxx>
To: amsat bb <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Digital Satellites Question
Message-ID:
<CALdCfNJXYcYZekbyeCXaNQj1GbApnwzPE+33ePrhfY2MWKv03w@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
> The biggest load in a communications satellite....
> is almost always the downlink RF power amplifier(s)...
True for some, not true for others. The locations of ham operators are
only about 10% of the earths surface. 90% of transmitter power can be
saved if the transmitter is not left on 100% of the time.
An APRS satellite takes advantage of this by knowing not only are there
users only 10% of the time, but even over a saturated ham area, the TX/RX
duty cycle cannot exceed 40% or so. The result is that the transmitter is
only on for 4% of the orbit. This means we can run a 5W transmitter to
make the packets hearable on an HT with a stock antenna, but that the
transmitter AVERAGE power is only 200 mW (less power than the receiver).
And by putting the downlink on 2m instead of UHF, there is another 9 dB
advantage to OMNI anennas. Add that to the 10 dB advantage of running a 5W
transmitter instead of 0.5W and you can see that an APRS cubesat can have
almost 19 dB downlink advantage over the typical UHF 0.5W downlink.
(theoretically)...
Many other factors of course are involved, but we need a mix of satellites
and modes, but the above is why I like AX.25 for short bursty texting and
data for a large number of people to share in a short period of time.
Bob, WB4APR
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Message: 2
Date: Mon, 28 Jul 2014 14:19:20 -0400
From: Paul Stoetzer <n8hm@xxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] LituanicaSAT-1 (LO-78) Decayed
Message-ID:
<CABzOSOoXgDeHo1jOWthi7sDrFod2V+Z0pRHiaEwSSGThKS-ayQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
According to Space-Track.org, LO-78 decayed early this morning:
39569 LITUANICASAT 1 1998-067EN LTU 2014-07-28 13:29:00 2014-07-28
0:00:00 0.096 decay_msg TLE Historical
Congratulations to all who were involved in this successful project
and we look forward to any future Lithuanian amateur radio satellite
projects.
73,
Paul Stoetzer, N8HM
Washington, DC
------------------------------
Message: 3
Date: Mon, 28 Jul 2014 11:43:17 -0700
From: Roland Zurmely <py4zbz@xxxxx.xxx>
To: AMSAT <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Cape-2 Voice Repeater
Message-ID:
<1406572997.75733.YahooMailNeo@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
Successful voice repeater command:
http://www.qsl.net/py4zbz/C2vr2807.wav
73 de Roland ?PY4ZBZ ?GH70un
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Message: 4
Date: Mon, 28 Jul 2014 21:14:51 +0100
From: M5AKA <m5aka@xxxxx.xx.xx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] AMSAT-UK Colloquium Pictures
Message-ID:
<1406578491.64355.YahooMailNeo@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
I have added some of the AMSAT-UK International Space Colloquium pictures
taken by Mike Rupprecht DK3WN to the AMSAT-UK Facebook page, see
https://www.facebook.com/media/set/?set=a.739813039395081.1073741828.208113275
898396
If anyone else has any pictures of the event which I can use can you email
them to me (max 20 meg attachment) or send Dropbox / Flickr / Instagram link.
----
Trevor M5AKA
AMSAT-UK
Website http://amsat-uk.org/
Facebook https://www.facebook.com/amsatuk
Twitter https://twitter.com/AMSAT_UK
----
------------------------------
Message: 5
Date: Mon, 28 Jul 2014 23:16:13 +0100
From: M5AKA <m5aka@xxxxx.xx.xx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Enhanced FUNcube-1 Dashboard App now available
Message-ID:
<1406585773.61146.YahooMailNeo@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
See http://amsat-uk.org/2014/07/28/enhanced-funcube-1-dashboard-app/
Also on the AMSAT-UK site :
Murray Niman G6JYB Appointed RSGB Spectrum Chair
http://amsat-uk.org/2014/07/28/murray-niman-g6jyb-appointed-rsgb-spectrum-chai
r/
UK Space Agency: UKube-1 Success
http://amsat-uk.org/2014/07/28/uk-space-agency-ukube-1-success/
ARISS contact planned with ESA Space Camp, Fleetwood, UK
http://amsat-uk.org/2014/07/24/ariss-contact-planned-with-esa-space-camp-fleet
wood-uk/
Some pictures from last weekend's Colloquium? are now on the Facebook page at
https://www.facebook.com/media/set/?set=a.739813039395081.1073741828.208113275
898396
----
Trevor M5AKA
AMSAT-UK
Website http://amsat-uk.org/
Facebook https://www.facebook.com/amsatuk
Twitter https://twitter.com/AMSAT_UK
----
------------------------------
Message: 6
Date: Mon, 28 Jul 2014 17:59:50 -0500
From: "Nick Pugh K5QXJ" <quadpugh@xxxxxxxxx.xxx>
To: <AMSAT-BB@xxxxx.xxx>
Subject: [amsat-bb] test
Message-ID: <015101cfaab7$a3dbecb0$eb93c610$@xxx>
Content-Type: text/plain; charset="us-ascii"
Thanks
nick
Office 337 593 8700
Cell 337 258 2527
Helping UL become a world Class Engineering and Educational School
------------------------------
Message: 7
Date: Tue, 29 Jul 2014 01:29:40 -0400
From: Lizeth Norman <normanlizeth@xxxxx.xxx>
To: "<, amsat-bb@xxxxx.xxxxxxx " <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Yaesu G-5500 grounding question
Message-ID:
<CAJUhCTOZC0sChh-r8HUPC4+CA=fqB6p35Zwb653sj=X+RaD9OQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Hi all!
I want to use the ground conductor that is in both the elevation and
azimuth rotators on pin #3 on the rear connectors.
The plug on the rotator controller is a two prong polarized type.
The upshot of this is that there is no actual connection to earth ground at
the chassis.
Can I just add a grounding lug to the back of the controller and attach it
to earth ground?
The reason this is an issue is that I have installed mast (fiberglass cross
arm, really) mount preamps. My radios are battery powered, hence no real
ground at the end of the coax.
Treading lightly here as there are ogres lurking.
Norm n3ykf
------------------------------
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End of AMSAT-BB Digest, Vol 9, Issue 260
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