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CX2SA > SATDIG 21.04.13 21:04l 1114 Lines 43963 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Antares Launch Attempt Scrubbed (B J)
2. Re: Mount an Arrow on rotator with 2mverticalorhorizontal
(Ib Christoffersen)
3. Icom IC-910 For Sale (Dave Webb KB1PVH)
4. Re: Mount an Arrow on rotator with 2m verticalorhorizontal (i8cvs)
5. ANS-111 AMSAT News Service Weekly Bulletins (JoAnne Maenpaa)
6. Re: Mount an Arrow on rotator with 2m verticalorhorizontal
(Art McBride)
7. 'Bring Your Own Board? CubeSat Workshop July 19 (M5AKA)
----------------------------------------------------------------------
Message: 1
Date: Sat, 20 Apr 2013 20:51:47 +0000
From: B J <va6bmj@xxxxx.xxx>
To: amsat-bb <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Antares Launch Attempt Scrubbed
Message-ID:
<CAP7QzkPvdUM60HS3i-Y+=KohgGB92Zo95O8oGPvEPoUZTvPLaQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
http://www.nasaspaceflight.com/2013/04/orbital-antares-debut-launch-attempt/
http://spaceflightnow.com/antares/demo/status.html
Next attempt will apparently be tomorrow.
73s
Bernhard VA6BMJ @ DO33FL
------------------------------
Message: 2
Date: Sat, 20 Apr 2013 23:16:44 +0200
From: "Ib Christoffersen" <oz1my@xxxxxx.xx>
To: <kc6uqh@xxx.xxx>, "'i8cvs'" <domenico.i8cvs@xxx.xx>, "'Douglas
Phelps'" <dphelps1@xxxxxxxxx.xxx>, "'R.T.Liddy'" <k8bl@xxxxxxxxx.xxx>,
"'Amsat - BBs'" <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Mount an Arrow on rotator with
2mverticalorhorizontal
Message-ID: <CFAAFA2AAF664CE6A5CAB240B7554A47@xxx.xx>
Content-Type: text/plain; charset="iso-8859-1"
Hello Domenico, Art and the -bb,
My comment here is with the ARROWS antennas.
I think one thing is overlooked here.
We are dealing with two antennas on different frequencies.
And yes in this it may work since 435 MHz is 3 times the 145 MHz.
So 1 quarter wavelength on 145 MHz becomes 3 quarter wavelength on 435 MHz.
Therefore it may work impedance wise.
However there may be a problem with coupling between the two frequency
bands.
73 OZ1MY/Ib
-----Oprindelig meddelelse-----
Fra: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx P? vegne
af Art McBride
Sendt: 20 April 2013 19:47
Til: 'i8cvs'; 'Douglas Phelps'; 'R.T.Liddy'; 'Amsat - BBs'
Emne: [amsat-bb] Re: Mount an Arrow on rotator with 2mverticalorhorizontal
Domenico,
There are two solutions to use coax to combine two 50 Ohm antennas. 70.7 Ohm
cable (50 to 100) [Two 50 ohm antennas transformed by two lines to 100 Ohms
each, in parallel = 50 Ohms] and your suggestion using 35.4 Ohm cable
section (25 to 50) = [Two 50 ohm antennas connected in parallel = 25 Ohms,
transformed to 50 Ohms]
The interesting part is you do not save anything when using 75 Ohm coax as
1/4 wave sections (two in parallel =37.5 Ohms) VS two separate 75 ohm
sections one to each antenna.
Art, KC6UQH
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of i8cvs
Sent: Wednesday, April 17, 2013 5:00 AM
To: Douglas Phelps; R.T.Liddy; Amsat - BBs
Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
Hi Douglas,
Using two identical 50 ohm coax lenght you can't transform each 50 ohm
antenna impedance into 100 ohm but if you connect both 50 ohm coax cables
to a T connector than the resulting impedance at the common output of the T
connector will be 25 ohm i.e. two 50 ohm impedances in parallel and your
radio will see a VSWR of 50/25 = 2 and this is the reason it will not work !
BTW if you connect the above 25 ohm impedance to the input of a 1/4
electrical wavelenght long coax cable of 36 ohm impedance than at the output
of it you will get an impedance of 36^2 / 25 = 52 ohm toward the main feed
line with a good VSWR of about 1 in TX and RX
To build a 1/4 electrical wavelengt long of a transmission line of 36 ohm
impedance you can connect in parallel two 1/4 electrical wavelenght of
75 ohm coax cable like RG-59 or RG-11 i.e. 34,13 centimeters or 13,38
inches long for 145 MHz
BTW in this situation if both antennas are mounted in parallel one Vertical
and the other one Horizontal and if the elements are mounted on the same
plain with respect to the space than the resulting polarization of the
radiated field can be at 45 degrees like \ or at 135 degrees like /
depending at wich side of the dipoles the inner conductors of the 50 ohm
feed lines are connected.
73" de
i8CVS Domenico
----- Original Message -----
From: "Douglas Phelps" <dphelps1@xxxxxxxxx.xxx>
To: "R.T.Liddy" <k8bl@xxxxxxxxx.xxx>; <amsat-bb@xxxxx.xxx>
Sent: Tuesday, April 16, 2013 8:31 PM
Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m vertical
orhorizontal
> Any reason why, using identical coax lengths, you could not transform the
> impedance to 100 ohms and then use a T connector to sum both antenna
> signals and achieve 50 ohms to the radio? I know Transmit power will be
> 3 dB down at either antenna but is there any reason it will not work?
> Any antenna gurus out there?
>
_______________________________________________
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
_______________________________________________
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: 3
Date: Sat, 20 Apr 2013 17:44:12 -0400
From: Dave Webb KB1PVH <kb1pvh@xxxxx.xxx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Icom IC-910 For Sale
Message-ID:
<CAEMY9FfQDvmXOevFRBYceTxJuOc4NRyKbDd3rH8PGdK+gA=R_A@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
I'm selling my IC-910 with one UT-106 DSP unit and UX-910 1296 MHz. $1475
shipped USA only. Contact me direct.
Dave-KB1PVH
Sent from my Verizon Wireless Droid RAZR
------------------------------
Message: 4
Date: Sun, 21 Apr 2013 00:28:38 +0200
From: "i8cvs" <domenico.i8cvs@xxx.xx>
To: <kc6uqh@xxx.xxx>, "'Douglas Phelps'" <dphelps1@xxxxxxxxx.xxx>,
"'R.T.Liddy'" <k8bl@xxxxxxxxx.xxx>, "'Amsat - BBs'"
<amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
Message-ID: <000001ce3e16$b17105e0$0401a8c0@xxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Art, KC6UQH
Feeding a 50 ohm antenna with a odd numbar of 1/4 electrical wavelenght of
75 ohm coax cable you transform the 50 ohm antenna impedance into 100 ohm
and connecting two 100 ohm impedances in parallel you get again 50 ohm to
supply the system main fedline to TX and RX but using this solution the VSWR
into the 75 ohm coax cables is 75/50 = 1.5 and this VSWR represent losses
particularly at high frequencies from 435 MHz and up to 1296 MHz
On the other side feeding two 50 ohm antennas with the same lenghts of 50
ohm coax cables in parallel you get a 25 ohm impedance to be transformed
again into 50 ohm using a matching line of 37.5 ohm 1/4 electrical
wavelenght long made with two pieces of coax cable 1/4 electrical wavelenght
long but in this solution the VSWR into both 50 ohm feeding lines will be
a good 1 to 1 and the losses are not very high so that this second solution
seems to be preferable.
The 37.5 ohm Zo impedance power divider can be professionally built in air
using two sections of round copper tubing 1/4 wavelenght long using the
following formula:
Zo = 138 log (D/d)
10
where D is the inside diameter of the outer tubing and d is the outside
diameter of the inner tubing.
In this solutions the RF losses are less than using two sections of 75 ohm
coax cables in parallel each 1/4 electrical wavelenght long so that this
round copper tubing power divider solution seems to be preferred and it
is that I currently use up to 1296 MHz
73" de
i8CVS Domenico
----- Original Message -----
From: "Art McBride" <kc6uqh@xxx.xxx>
To: "'i8cvs'" <domenico.i8cvs@xxx.xx>; "'Douglas Phelps'"
<dphelps1@xxxxxxxxx.xxx>; "'R.T.Liddy'" <k8bl@xxxxxxxxx.xxx>; "'Amsat -
BBs'" <amsat-bb@xxxxx.xxx>
Sent: Saturday, April 20, 2013 7:47 PM
Subject: RE: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
> Domenico,
> There are two solutions to use coax to combine two 50 Ohm antennas. 70.7
> Ohm cable (50 to 100) [Two 50 ohm antennas transformed by two lines to
> 100 Ohms each, in parallel = 50 Ohms] and your suggestion using 35.4 Ohm
> cable section (25 to 50) = [Two 50 ohm antennas connected in parallel
> = 25 Ohms, transformed to 50 Ohms]
>
> The interesting part is you do not save anything when using 75 Ohm coax as
> 1/4 wave sections (two in parallel =37.5 Ohms) VS two separate 75 ohm
> sections one to each antenna.
>
> Art, KC6UQH
>
>
> -----Original Message-----
> From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
> Behalf Of i8cvs
> Sent: Wednesday, April 17, 2013 5:00 AM
> To: Douglas Phelps; R.T.Liddy; Amsat - BBs
> Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m
> verticalorhorizontal
>
> Hi Douglas,
>
> Using two identical 50 ohm coax lenght you can't transform each 50 ohm
> antenna impedance into 100 ohm but if you connect both 50 ohm coax cables
> to a T connector than the resulting impedance at the common output of the
> T connector will be 25 ohm i.e. two 50 ohm impedances in parallel and your
> radio will see a VSWR of 50/25 = 2 and this is the reason it will not
> work !
>
> BTW if you connect the above 25 ohm impedance to the input of a 1/4
> electrical wavelenght long coax cable of 36 ohm impedance than at the
> output of it you will get an impedance of 36^2 / 25 = 52 ohm toward
> the main feed line with a good VSWR of about 1 in TX and RX
>
> To build a 1/4 electrical wavelengt long of a transmission line of 36 ohm
> impedance you can connect in parallel two 1/4 electrical wavelenght of
> 75 ohm coax cable like RG-59 or RG-11 i.e. 34,13 centimeters or 13,38
> inches long for 145 MHz
>
> BTW in this situation if both antennas are mounted in parallel one
> Vertical and the other one Horizontal and if the elements are mounted on
> the same plain with respect to the space than the resulting polarization
> of the radiated field can be at 45 degrees like \ or at 135 degrees like /
> depending at wich side of the dipoles the inner conductors of the 50 ohm
> feed lines are connected.
>
>
> 73" de
>
> i8CVS Domenico
>
> ----- Original Message -----
> From: "Douglas Phelps" <dphelps1@xxxxxxxxx.xxx>
> To: "R.T.Liddy" <k8bl@xxxxxxxxx.xxx>; <amsat-bb@xxxxx.xxx>
> Sent: Tuesday, April 16, 2013 8:31 PM
> Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m vertical
> orhorizontal
>
> > Any reason why, using identical coax lengths, you could not transform
> > the impedance to 100 ohms and then use a T connector to sum both
> > antenna signals and achieve 50 ohms to the radio? I know Transmit
> > power will be 3 dB down at either antenna but is there any reason it
> > will not work?
> > Any antenna gurus out there?
> >
>
> _______________________________________________
> 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: 5
Date: Sat, 20 Apr 2013 20:45:30 -0500
From: "JoAnne Maenpaa" <k9jkm@xxxxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] ANS-111 AMSAT News Service Weekly Bulletins
Message-ID: <000201ce3e31$e8a59b50$b9f0d1f0$@xxx>
Content-Type: text/plain; charset="iso-8859-1"
AMSAT NEWS SERVICE
ANS-111
The AMSAT News Service bulletins are a free, weekly news and infor-
mation service of AMSAT North America, The Radio Amateur Satellite
Corporation. ANS publishes news related to Amateur Radio in Space
including reports on the activities of a worldwide group of Amateur
Radio operators who share an active interest in designing, building,
launching and communicating through analog and digital Amateur Radio
satellites.
The news feed on http://www.amsat.org publishes news of Amateur
Radio in Space as soon as our volunteers can post it.
Please send any amateur satellite news or reports to:
ans-editor at amsat.org.
In this edition:
* April 19 Soyuz-2-1B Launch Plans Cubesat Deployment on April 21
* April 21 Antares Launch to Orbit Three PhoneSat Cubesats
* April 25 China CZ-2D to Launch TURKSAT-3USAT Linear Transponder
* May 3 Vega Launch from Kourou to Orbit ESTCube-1 CubeSat
* AMSAT-NA Board of Directors Nominations Solicited
* ARISS School Contacts
* Order AMSAT/TAPR Dayton Banquet Tickets in the AMSAT Store
* Registration for the SA AMSAT Space Symposium is Now Open
* Inspiration and Success: The Story Behind N1LF's 1st Satellite QSO
* RockOn 2013 University Rocket Science Workshop
* Satellite Shorts From All Over
SB SAT @ AMSAT $ANS-111.01
ANS-111 AMSAT News Service Weekly Bulletins
AMSAT News Service Bulletin 111.01
>From AMSAT HQ SILVER SPRING, MD.
April 21, 2013
To All RADIO AMATEURS
BID: $ANS-111.01
*****************************************************************
* Volunteers are needed to help at the AMSAT booth at Dayton. *
* Steve Belter N9IP, is looking for volunteers to help man the *
* AMSAT booth during the 2013 Hamvention. If you are willing *
* to help at the Hamvention, please send an e-mail by April 30 *
* to Steve Belter, n9ip@xxxxx.xxx. *
* *
* Monitor the 'AMSAT at Dayton Hamvention 2013' link on the new *
* AMSAT Web Site http://www.amsat.org for the latest AMSAT at *
* Dayton news and developments *
*****************************************************************
---------------------------------------------------------------------
April 19 Soyuz-2-1B Launch Plans Cubesat Deployment on April 21
A Soyuz-2-1b from the Baikonur launch facility, in Kazakhstan on
April 19, 2013 now has four cubesat missions using amateur radio
frequencies and three commercial and science missions on-orbit:
Satellite Downlink Mode
---------- --------------- ------------------
OSSI-1 145.980/437.525 CW/1200bps (Amateur Band)
SOMP 437.485 1200, 9600bps BPSK (Amateur Band)
BEESAT-2/3 435.950 4800bps GMSK/Mobitex (Amateur Band)
Bion-M1 Biological research satellites
AIST Measurement of the Earth's geomagnetic field
435 MHz downlink/145 MHz command & control uplink
Dove-2 Commercial technology demonstration mission
450 MHz band downlink
Additional information and photos can be viewed on the AMSAT-UK web:
http://amsat-uk.org/2013/04/17/soyuz-cubesat-launch/
This page includes additional information on the planned deployment
of the cubesats from the P-POD canisters: "Unusually the CubeSats
will not be deployed straight after launch. All four CubeSats:
OSSI-1, BEESAT-3, SOMP, and BEESAT-2 will be deployed around 10:45
UTC on Sunday, April 21. Until then orbital maneuvers will be car-
ried out to achieve a circular orbit at 575 km altitude."
OSSI-1 Deployed on April 19
---------------------------
145.980 MHz CW, 437.525 MHz 1k2
OSSI-1, the Open Source Satellite Initiative satellite is a cubesat
developed by Hojun Song DS1SBO. In addition to the radio beacons
OSSI-1 also carries a 44 watt LED optical beacon to flash Morse Code
messages to observers on Earth.
The development of the satellite has been documented on the Open
Source Satellite Initiative Blog http://opensat.cc/blog/ and the
Wiki http://opensat.cc/wiki/
http://www.youtube.com/watch?v=YUOL0zSY6cg
AMSAT-UK coverage can be read at:
http://amsat-uk.org/2013/04/19/ossi-1-amateur-radio-cubesat-launched/
BEESAT 3, BEESAT 2, SOMP, AIST and Dove-2 are expected to be separat-
ed from BION M1 in two batches on Sunday, April 21.
SOMP
----
Downlink on 437.485 MHz including CW, 1k2 and 9k6 BPSK, AX25 FSK,
and AO40 standard 400bit/s BPSK
The Student Oxygen Measurement Project (SOMP) is a cubesat devel-
oped by students of the Technische Universit?t Dresden, Germany,
organized in the Students? Research Group for Spacecraft Engineer-
ing in Dresden (STARD). SOMP will be a standard sized single CubeSat
with one payload side and five sides with two solar cells each.
http://phpweb.tu-dresden.de/stard/SOMP/?lang=en
http://tinyurl.com/SOMP-AMSAT-UK-Posting
BEESAT-2/3 (Berlin Experimental and Educational Satellite)
435.950 MHz, 4k8 GMSK (both satellites)
BEESAT-2 is a cubesat-sized vehicle carries a technology experiment
using gyros and sensors for precise orientation.
BEESat-3 is another cubesat-sized vehicle that will test high-speed
data links (up to 1MB/s).
http://www.raumfahrttechnik.tu-berlin.de/beesat/
The above cubesat missions and the scientific/commercial missions
are also documented on Mineo Wakita's (JE9PEL) web page at:
http://www.ne.jp/asahi/hamradio/je9pel/ossisomp.htm
[ANS thanks AMSAT-UK and Mineo Wakita, JE9PEL for the above infor-
mation]
---------------------------------------------------------------------
April 21 Antares Launch to Orbit Three PhoneSat Cubesats
Three PhoneSat cubesats are now on-orbit following the launch of the
Orbital Sciences Corporation Antares(TM) rocket from NASA?s Wallops
Flight Facility (WFF) in eastern Virginia. The originally scheduled
April 17 launch attempt was scrubbed. April 21 is the next planned
launch attempt.
All three of the Phonesat cubesats carries an amateur radio payload
on 437.425 MHz. Each cubesat will transmit during individual time
slots. All three satellites transmit using AFSK (1200 bps) modula-
tion, AX.25 packet coding and have vertical linear polarization. The
two PhoneSat 1.0 satellites, Graham and Bell, transmit with a period-
icity of respectively 28 seconds and 30 seconds. The PhoneSat 2.0
beta satellite, Alexander, transmit with a periodicity of 25 seconds.
The PhoneSat web at http://www.phonesat.org/ provides access to the
"Dashboard" allowing you to track the location of our satellites in
real time. Detailed information on the downlink packet telemetry
format can be found on this page. The callsign will be KJ6KRW.
The orbit is very low (270km x 300km, 51.6deg) and the cubesats are
expected to only remain on-orbit for two weeks. The satellites are
battery powered with no additional charging from solar cells.
The Dove-2 commercial satellite is believed to use 2420.0 MHz for
its downlink.
[ANS thanks the PhoneSat Team for the above information]
---------------------------------------------------------------------
April 25 China CZ-2D to Launch TURKSAT-3USAT Linear Transponder
TAMSAT reports the TURKSAT-3USAT, the first communication nanosatel-
lite mission of ITU, Istanbul Technical University, Istanbul, Turkey
is expected to launch on April 25 aboard China's Chang Zheng-2D
rocket. Also aboard this launch will be Ecuador's NEE 01 Pegaso 1U
cubesat and Argentina's CubeBug-1 satellite.
TURKSAT-3USAT is a three unit CubeSat developed to provide SSB/CW
communications in a 680 km Low Earth Orbit. It will fly a V/U linear
transponder developed by TAMSAT, the Turkish Amateur Satellite Tech-
nologies Organisation.
+ Uplink center frequency 145.965 MHz
(145.940-145.990 MHz bandwidth)
Receive sensitivity -120 dBm
+ Downlink center frequency 435.225 MHz
(435.200-435.250 MHz bandwidth)
Output power 30 dBm (1W)
+ CW beacon on 437.225 MHz
Additional information can be accessed on-line at:
http://www.tamsat.org.tr/tr/turksat-3usat-is-almost-ready/
http://www.uk.amsat.org/?p=12670
CUBEBUG-1 Heading for Orbit Includes Amateur Radio Digipeater
-------------------------------------------------------------
CubeBug-1 is the first technology demonstration mission for a new
CubeSat platform design (mechanics, hardware and software) intended
to be released as Open Source and Open Hardware for its use in Ama-
teur projects, University projects and research labs.
The project is sponsored by the Argentina Ministry of Science,
Technology and Productive Innovation.
Payloads on this first mission include:
+ An ARM based on-board computer
+ A nano-reaction wheel with its driver circuit
+ A low resolution camera
+ All based on COTS components
CubeBug-1 is a 2U CubeSat and the team are planning to use half
duplex communications on 437.445 MHz with 9k6 GMSK data. Tele-
metry information is at http://1.cubebug.org/coms/telemetry
After the technology demonstration part of the mission is over, the
satellite will enter a mode that will include services to the Ama-
teur radio community, including a Digipeater, science data downloads
from the payload (including images if possible).
Watch a CubeBug-1 video at http://vimeo.com/56055215
CubeBug-1 website http://1.cubebug.org/
Follow CubeBug-1 on Twitter @xxxxxxxx
[ANS thanks AMSAT-UK, the CubeBug Team and TAMSAT for the above
information]
---------------------------------------------------------------------
May 3 Vega Launch from Kourou to Orbit ESTCube-1 CubeSat
Estonia?s first CubeSat ESTCube-1, amateur radio callsign ES5E/S,
is planned to launch from the ESA Spaceport in Kourou in the Cari-
bbean on May 3, 2013 aboard an ESA VEGA rocket.
Built by students at the University of Tartu ESTCube-1 the main
mission of the satellite is to test electric solar wind sail tech-
nology, a novel space propulsion technology that could revolution-
alize transportation within the solar system. It will deploy a 10
meter conductive electrodynamic tether and the force interacting
with the tether will be measured.
The IARU Amateur Satellite Frequency Coordination Panel have pub-
lished these frequencies for ESTCube-1:
+ 437.250 MHz ? CW beacon, callsign ES5E/S
+ 437.505 MHz ? 9600 bps AX.25 telemetry, callsign ES5E-11
More information and a video has been posted at:
http://amsat-uk.org/?p=14774
Additional news of the launch is posted at:
http://tinyurl.com/April-Vega-Launch (Space-Travel.com)
[ANS thanks AMSAT-UK and the University of Tartu ESTCube-1 Team for
the above information]
---------------------------------------------------------------------
AMSAT-NA Board of Directors Nominations Solicited
It is time to submit nominations for the upcoming open seats on the
AMSAT-NA Board of Directors. A nomination requires either one Member
Society or five current individual members in good standing to
nominate an AMSAT member for the position. Four director's terms
expire this year: Barry Baines, WD4ASW, Alan Biddle, WA4SCA, Drew
Glasbrenner, K04MA, and Tony Monteiro, AA2TX.
In addition to traditional submission of written nominations, which
remains unchanged and is the preferred method, nominations may be
made by electronic means. These include e-mail, FAX, or electronic
image of a petition. Electronic petitions should be sent to
MARTHA at AMSAT.ORG or faxed to 301-608-3410. Written nominations,
consisting of names, calls and individual signatures should be mailed
to: AMSAT-NA, 850 Sligo Ave #600, Silver Spring, MD, 20910. No matter
what means is used, petitions MUST arrive no later than June 15th at
the AMSAT-NA office. If the nomination is a traditional written
nomination, no other action is required. If it is other than this,
i.e. electronic, a verifying traditional written petition MUST be
received at the AMSAT-NA office at the above address within 7 days
following the close of nominations on June 15th. ELECTRONIC
SUBMISSIONS WITHOUT THIS SECOND, WRITTEN VERIFICATION ARE NOT VALID
UNDER THE EXISTING AMSAT-NA BYLAWS.
[ANS thanks Alan, WA4SCA, AMSAT Corporate Secretary for the above
information]
---------------------------------------------------------------------
ARISS School Contacts
John McCrae High School, Nepean, Ontario, Canada
------------------------------------------------
The International Space Station school contact with participants at
John McCrae High School, Nepean, Ontario, Canada on 17 April was
successful. The contact was completed via telebridge between OR4ISS
and IK1SLD.
John McCrae Secondary school is named after the Canadian poet and
doctor who during World War I, wrote the famous war memorial poem
"In Flanders Fields". With this heritage in mind the school hosts
large community Remembrance Day ceremonies every November 11 and
celebrates community works of art in the "Red Poppy" gallery. John
McCrae students consistently rank among the best academic perform-
ers in the province, gaining post secondary acceptance across North
America and winning many entrance scholarships.
Gray Mountain Primary School, Whitehorse, Yukon, Canada
-------------------------------------------------------
The International Space Station school contact with participants at
Gray Mountain Primary School, Whitehorse, Yukon, Canada on 23 April
was successful. The contact was completed via telebridge with IK1SLD.
The incredible opportunity to speak with the ISS and Chris Hadfield
has sparked a frenzy of space related themes and ideas throughout the
school and inspired the community. The small school has been trans-
formed into a space education station with student-created learning
displays and artwork throughout. The kids have been reading and writ-
ing using space to inspire imaginations and incorporating space ex-
ploration into math and science lessons. A local artist is coming
to build a life size Soyuz spacecraft out of recycled materials with
the Grade 2s and 3s.
Upcoming School Contacts This Week:
-----------------------------------
+ Bates College Museum of Art, Lewiston, ME, telebridge via IK1SLD
on Tuesday, April 23 at 14:38:47 UTC.
+ Maani Ulujuk Ilinniarvik (MUI), Rankin Inlet, Nunavut, Canada,
telebridge via IK1SLD on Thursday, April 25 at 14:34:36 UTC.
+ Istituto d'Istruzione Superiore Euclide, Bari, Italy, telebridge
via IZ7RTN on Saturday, April 27 at 11:17:19 UTC.
ARISS is requesting listener reports for the above contacts. Due to
issues with the Kenwood radio that are not fully understood at pre-
sent, the Ericsson radio is going to be used for these contacts.
ARISS thanks everyone in advance for their assistance.
[ANS thanks ARISS for the above information]
---------------------------------------------------------------------
Order AMSAT/TAPR Dayton Banquet Tickets in the AMSAT Store
AMSAT Hotel News
----------------
Per Martha at the AMSAT Office, the entire block of AMSAT rooms for
Hamvention 2013 are now taken, and no more will be available.
Friday Evening AMSAT/TAPR Banquet at Dayton
-------------------------------------------
Tickets for the dinner are $30 each, and must be purchased from the
AMSAT Store at http://store.amsat.org/catalog/ by Tuesday, May 14.
The dinner will be held at:
The Kohler Presidential Banquet Center
4548 Presidential Way
Kettering, OH 45429
Doors open at 1830 for a cash bar with buffet dinner served at 1915.
Seating is limited to the number of meals we reserve with the Kohler
caterers, based on the number of tickets sold by the deadline. Tick-
ets will not be sold at Dayton, but tickets purchased online may be
collected at the AMSAT booth (444-446 and 433-435).
Join us for a fun evening with good food, great company, and an
outstanding speaker.
This year's speaker will be Bruce Perens, K6BP, with a humorous his-
tory of technology evangelism: "The Evangelist's Dilemma: Driving
New Ideas With Nothing But Words." As you can imagine, when you're
promoting new ideas, there are things that inevitably go wrong. Bruce
will pull examples from his history with Open Source, No-Code, Soft-
ware Freedom, Codec2, and Open Hardware, and he'll introduce a few
of the new battle grounds.
[ANS thanks AMSAT's 2013 Dayton Committee for the above information]
---------------------------------------------------------------------
Registration for the SA AMSAT Space Symposium is Now Open
SA AMSAT will hold its annual space symposium in Pretoria at the
Innovation Hub on Saturday 18 May 2012. The keynote speaker will
be McLean Sibanda, the CEO of the Innovation Hub with the subject
"Innovation is everyone's business". The agenda is packed with in-
teresting presentations and demonstrations. The symposium is spon-
sored by Telkom.
Make your booking now to benefit from the early registration package.
Full details and the registration form are available on
http://www.amsatsa.org.za/SpceSymp2013.htm.
SARL and SA AMSAT members enjoy preferential rates. The registration
fee includes a CD of all the papers as well as refreshments and a
light lunch.
[ANS thanks the SARL News in English for April 13, 2013 for the
above information]
---------------------------------------------------------------------
Inspiration and Success: The Story Behind N1LF's 1st Satellite QSO
Les Rayburn, N1LF sent a message to the amsat-bb on April 14 which
describes his ham radio journey to his first amateur satellite con-
tact via FO-29.
Les wrote:
I've been a ham well over 40 years, since my childhood. Back then, I
could barely afford the Heathkit transmitter, Halicrafters receiver,
knife switch, and longwire antenna that made up my shack.
My elmer used to let me borrow his copy of QST and I'd dream about
all the great adventures that I'd have "someday" in ham radio. Being
a child of the Space Age, key among them were anything related to
the New Frontier.
EME (Moonbounce), Meteor Scatter, and satellites all seemed like
the stuff of science fiction---and I longed to experience them all.
But they were exotic, and required equipment far beyond my reach.
I resolved to accomplish them all someday and added them to a sort
of ham radio "bucket list" that I hoped to accomplish before my ham
career was over.
Five years ago, shortly after getting started in weak signal VHF
work, I checked off the first item on that list. Working meteor
scatter contacts with the aid of WSJT software, and during a Per-
seid shower, even using SSB. What a thrill to make contacts off
the ionized gasses of those tiny rocks. Thanks Joe Taylor!
Tonight, I managed to check off a second. I worked Art, K4YYL on
FO-29, a Japanese amateur satellite!
My journey to the "birds" started about a month ago when I joined
AMSAT, determined that 2013 was going to be "the year" when I fin-
ally got active on satellites. I purchased a copy of SATPC32 soft-
ware, because I knew that it could control my IC-910H--hopefully
making it easier to get active.
After listening to a few passes on both the FM and the SSB/CW birds,
I decided to try my luck on the less-crowded FO-29. A brief CQ was
quickly answered by Art. I adjusted the tuning knob just a bit to
correct for the Doppler effect, and voila! there he was clear as a
bell.
We had a brief QSO of perhaps ten minutes or so, and then we signed.
I was quickly called by K4FEG near Memphis in EM55---who just wanted
to welcome me to the birds!
Man, what a thrill! And it wasn't tough at all.
I'm using a 7 element 432 antenna tilted up to 15 degrees (fixed)
and a 6 element 2 Meter beam tilted up to about 10 degrees (fixed)
both inside my crowded attic. The SSB Electronics pre-amp helps a
ton on 432, and the 1/2" hardline makes sure that I don't lose too
much signal. So far, I've been able to copy the birds down to about
2 degrees above the horizon using this setup.
Now to attempt that EME contact! I've got a 12 element Yagi just
waiting to deploy in the driveway once the weather warms a bit. Hop-
ing to use WSJT to work one of the monster stations on EME. All this
in a deed-restricted HOA neighborhood.
I wasted 35+ years on HF----man, all the fun really is in the World
Above 50 MHz! Thanks for helping to make a boy's dreams come true at
age 51!
[ANS thanks and congratulates Les Rayburn, N1LF for the above
information]
---------------------------------------------------------------------
RockOn 2013 University Rocket Science Workshop
U.S. university and community college faculty and students are
invited to a weeklong workshop to learn how to build and launch
a scientific experiment into space. NASA's Wallops Flight Facility
in Virginia is hosting the RockOn 2013 workshop June 15-20, 2013,
in partnership with the Colorado and Virginia Space Grant Consortia.
Workshop participants must be U.S. citizens. The registration dead
line for the workshop is May 1, 2013.
The hands-on workshop teaches participants to build experiments that
fly on sounding rockets. During the week, participants will work to-
gether in teams of three to construct and integrate a sounding rocket
payload from a kit. On the fifth day of the workshop, the experiments
will fly on a sounding rocket expected to reach an altitude of more
than 70 miles.
Each experiment will provide valuable scientific data, analyzed as
part of the student-led science and engineering research. The pro-
gram engages faculty and students in science, technology, engineer-
ing and mathematics skills critical to NASA's future engineering,
scientific and technical missions.
For more information about RockOn and to register online, visit:
http://spacegrant.colorado.edu/national-programs/rockon-2013-home
Questions about the workshop or the registration process should be
directed to Chris Koehler by email at koehler@xxxxxxxx.xxx or by
telephone at 303-492-3141.
[ANS thanks the NASA Education Express Message -- April 18, 2013
for the above information]
---------------------------------------------------------------------
Satellite Shorts From All Over
+ A web-based Software Defined Radio for the 5, 7 and 14 MHz bands
is now available on the new RSGB website. The "Web SDR receiver"
link can be found under the "MyRSGB" drop-down menu. Also on the
new site are "Live DX Cluster" and "Live solar data" pages under
the "News" drop-down menu. See: http://www.rsgb.org/
+ The Florida Today newspaper published a story about the Merritt
Island High School CubeSat project called StangSat. See:
http://amsat-uk.org/2013/04/11/merritt-island-high-students-cubesat/
+ Video from the CanSat Leader Training Program is posted at:
http://www.youtube.com/watch?v=SwK3dLrUmEQ&feature=player_embedded
CanSats are tiny satellites, built to fit in the same space as a
soda-can. UNISEC is running a training program in Japan later this
year, to train people on how to build and teach building of these
ingenious devices. See: http://www.unisec.jp/flash/index-e.html
(via Southgate)
+ NASA has posted videos celebrating Earth Month and specifically
Earth Day (April 22) from ISS imagery:
http://www.youtube.com/watch?feature=player_embedded&v=Y0Q0Hene1LY
Another Earth Month video from satellite imagery is posted at:
http://www.youtube.com/watch?v=X2c8Ozis-mo&feature=player_embedded
+ The Goddard Space Flight Center posted the best views of Earth
from space in the last year, including true color satellite images,
Earth science data visualizations, time lapses from the Interna-
tional Space Station, and computer models:
http://www.youtube.com/watch?feature=player_embedded&v=sckOSMf-LpY
+ Two UrtheCast cameras - one medium-resolution still camera and one
high-resolution video camera are planned for launch on the Progress
53P cargo supply mission on October 16, 2013. The cameras will be
installed on the Zvezda Service Module of the Russian segment of
the ISS, during its crew spacewalks. Soon after installation,
Earth imagery and video will begin transmitting to ground stations
across the globe via an existing high-speed downlink from the ISS,
then streamed to the web. Read the full story at:
http://spaceref.com/news/viewpr.html?pid=40490
[ANS thanks everyone for the above information]
---------------------------------------------------------------------
In addition to regular membership, AMSAT offers membership in the
President's Club. Members of the President's Club, as sustaining
donors to AMSAT Project Funds, will be eligible to receive addi-
tional benefits. Application forms are available from the AMSAT
Office.
Primary and secondary school students are eligible for membership
at one-half the standard yearly rate. Post-secondary school students
enrolled in at least half time status shall be eligible for the stu-
dent rate for a maximum of 6 post-secondary years in this status.
Contact Martha at the AMSAT Office for additional student membership
information. And with that please keep in mind that the integral of
(1/cabin)d(cabin) is a natural log cabin, of course!
73,
This week's ANS Editor,
JoAnne Maenpaa, K9JKM
K9JKM at amsat dot org
------------------------------
Message: 6
Date: Sat, 20 Apr 2013 22:18:23 -0700
From: "Art McBride" <kc6uqh@xxx.xxx>
To: "'i8cvs'" <domenico.i8cvs@xxx.xx>, "'Douglas Phelps'"
<dphelps1@xxxxxxxxx.xxx>, "'R.T.Liddy'" <k8bl@xxxxxxxxx.xxx>, "'Amsat
- BBs'" <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
Message-ID: <60143CA943C845199BE0FD2BF078215B@xxxxxx>
Content-Type: text/plain; charset="us-ascii"
Domenico,
Loss for a 1/4 wave resonant line is small. RG 4121/2 5/8 and 3/4 inch 75
Ohm line for CATV is very low loss. If you build your own Coax the impedance
should be 35.4 Ohms for your preferred match.
73, Art
-----Original Message-----
From: i8cvs [mailto:domenico.i8cvs@xxx.xxx
Sent: Saturday, April 20, 2013 3:29 PM
To: kc6uqh@xxx.xxxx 'Douglas Phelps'; 'R.T.Liddy'; 'Amsat - BBs'
Subject: Re: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
Hi Art, KC6UQH
Feeding a 50 ohm antenna with a odd numbar of 1/4 electrical wavelenght of
75 ohm coax cable you transform the 50 ohm antenna impedance into 100 ohm
and connecting two 100 ohm impedances in parallel you get again 50 ohm to
supply the system main fedline to TX and RX but using this solution the VSWR
into the 75 ohm coax cables is 75/50 = 1.5 and this VSWR represent losses
particularly at high frequencies from 435 MHz and up to 1296 MHz
On the other side feeding two 50 ohm antennas with the same lenghts of 50
ohm coax cables in parallel you get a 25 ohm impedance to be transformed
again into 50 ohm using a matching line of 37.5 ohm 1/4 electrical
wavelenght long made with two pieces of coax cable 1/4 electrical wavelenght
long but in this solution the VSWR into both 50 ohm feeding lines will be
a good 1 to 1 and the losses are not very high so that this second solution
seems to be preferable.
The 37.5 ohm Zo impedance power divider can be professionally built in air
using two sections of round copper tubing 1/4 wavelenght long using the
following formula:
Zo = 138 log (D/d)
10
where D is the inside diameter of the outer tubing and d is the outside
diameter of the inner tubing.
In this solutions the RF losses are less than using two sections of 75 ohm
coax cables in parallel each 1/4 electrical wavelenght long so that this
round copper tubing power divider solution seems to be preferred and it
is that I currently use up to 1296 MHz
73" de
i8CVS Domenico
----- Original Message -----
From: "Art McBride" <kc6uqh@xxx.xxx>
To: "'i8cvs'" <domenico.i8cvs@xxx.xx>; "'Douglas Phelps'"
<dphelps1@xxxxxxxxx.xxx>; "'R.T.Liddy'" <k8bl@xxxxxxxxx.xxx>; "'Amsat -
BBs'" <amsat-bb@xxxxx.xxx>
Sent: Saturday, April 20, 2013 7:47 PM
Subject: RE: [amsat-bb] Re: Mount an Arrow on rotator with 2m
verticalorhorizontal
> Domenico,
> There are two solutions to use coax to combine two 50 Ohm antennas. 70.7
> Ohm cable (50 to 100) [Two 50 ohm antennas transformed by two lines to
> 100 Ohms each, in parallel = 50 Ohms] and your suggestion using 35.4 Ohm
> cable section (25 to 50) = [Two 50 ohm antennas connected in parallel
> = 25 Ohms, transformed to 50 Ohms]
>
> The interesting part is you do not save anything when using 75 Ohm coax as
> 1/4 wave sections (two in parallel =37.5 Ohms) VS two separate 75 ohm
> sections one to each antenna.
>
> Art, KC6UQH
>
>
> -----Original Message-----
> From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
> Behalf Of i8cvs
> Sent: Wednesday, April 17, 2013 5:00 AM
> To: Douglas Phelps; R.T.Liddy; Amsat - BBs
> Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m
> verticalorhorizontal
>
> Hi Douglas,
>
> Using two identical 50 ohm coax lenght you can't transform each 50 ohm
> antenna impedance into 100 ohm but if you connect both 50 ohm coax cables
> to a T connector than the resulting impedance at the common output of the
> T connector will be 25 ohm i.e. two 50 ohm impedances in parallel and your
> radio will see a VSWR of 50/25 = 2 and this is the reason it will not
> work !
>
> BTW if you connect the above 25 ohm impedance to the input of a 1/4
> electrical wavelenght long coax cable of 36 ohm impedance than at the
> output of it you will get an impedance of 36^2 / 25 = 52 ohm toward
> the main feed line with a good VSWR of about 1 in TX and RX
>
> To build a 1/4 electrical wavelengt long of a transmission line of 36 ohm
> impedance you can connect in parallel two 1/4 electrical wavelenght of
> 75 ohm coax cable like RG-59 or RG-11 i.e. 34,13 centimeters or 13,38
> inches long for 145 MHz
>
> BTW in this situation if both antennas are mounted in parallel one
> Vertical and the other one Horizontal and if the elements are mounted on
> the same plain with respect to the space than the resulting polarization
> of the radiated field can be at 45 degrees like \ or at 135 degrees like /
> depending at wich side of the dipoles the inner conductors of the 50 ohm
> feed lines are connected.
>
>
> 73" de
>
> i8CVS Domenico
>
> ----- Original Message -----
> From: "Douglas Phelps" <dphelps1@xxxxxxxxx.xxx>
> To: "R.T.Liddy" <k8bl@xxxxxxxxx.xxx>; <amsat-bb@xxxxx.xxx>
> Sent: Tuesday, April 16, 2013 8:31 PM
> Subject: [amsat-bb] Re: Mount an Arrow on rotator with 2m vertical
> orhorizontal
>
> > Any reason why, using identical coax lengths, you could not transform
> > the impedance to 100 ohms and then use a T connector to sum both
> > antenna signals and achieve 50 ohms to the radio? I know Transmit
> > power will be 3 dB down at either antenna but is there any reason it
> > will not work?
> > Any antenna gurus out there?
> >
>
> _______________________________________________
> 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: 7
Date: Sun, 21 Apr 2013 15:37:17 +0100 (BST)
From: M5AKA <m5aka@xxxxx.xx.xx>
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] 'Bring Your Own Board? CubeSat Workshop July 19
Message-ID:
<1366555037.7709.YahooMailClassic@xxxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=utf-8
Surrey Space Centre (SSC) and AMSAT-UK invite anyone with CubeSat equipment
to a ?Bring Your Own Board? (BYOB) workshop being held at the Surrey Space
Centre, Guildford, UK on Friday, July 19. Admittance to the Workshop is
free, see
http://amsat-uk.org/2013/04/21/bring-your-own-board-cubesat-workshop/
The AMSAT-UK International Space Colloquium takes place Saturday/Sunday July
20/21 at the Holiday Inn Hotel, Guildford, further details at
http://amsat-uk.org/colloquium/colloquium-2013/
73 Trevor M5AKA
AMSAT-UK website http://amsat-uk.org/
Facebook https://www.facebook.com/pages/AMSAT-UK/208113275898396
Twitter https://twitter.com/AMSAT_UK
----
------------------------------
_______________________________________________
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 8, Issue 124
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