ARISSat-1/KEDR at +10 Days: ON-ORBIT and OPERATIONAL August 14, 2011
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SB SAT @ AMSAT $ANS-226.01
ARISSat-1/KEDR at +10 Days: ON-ORBIT and OPERATIONAL
AMSAT News Service Bulletin 226.01
From AMSAT HQ SILVER SPRING, MD.
August 14, 2011
To All RADIO AMATEURS
BID: $ANS-226.01
Hundreds of reception reports have been received since ARISSat-1/KEDR
was deployed from the ISS. Full operational capability of the satel-
lite has been confirmed in the 10 days since the start of the mission
on August 3.
The satellite’s power system monitors the battery voltage and
switches between High power mode (continuous transmission) when
sunlight is charging the battery and Low power mode (40 seconds
transmit/2 minutes idle) when in eclipse. Telemetry data shows
that the ARISSat-1 Battery voltage is decreasing each eclipse
period. It therefore is taking longer for the battery to charge
up to 32.5V to allow the switch from Low Power to High Power when
the satellite enters an illumination period.
Kenneth Ransom, N5VHO has plotted the battery min/max for the last
8 days. The data shows that the battery voltage is decreasing at a
faster rate than expected. Kenneth’s graph can be found on the
arissat1.org site under FAQ: http://tinyurl.com/3e5c2y8 (arissat1.org)
The effect of this is that ARISSat-1/KEDR remains in Low power mode
for a period of time after exiting eclipse. The team recommend that
users take advantage of the High Power mode as much as possible over
the next few days.
435 MHz – 145 MHz Linear Transponder – OPERATIONAL
————————————————–
The linear transponder operates in Mode U/V (70 cm Up, 2m Down). It
is an 16 KHz wide inverting passband. The convention is to TX LSB on
the 435 MHz uplink and RX USB on the 145 MHz downlink. Several amateur
radio operators have been reporting successful contacts via the linear
transponder.
After the initial success with the linear transponder reported by
KO4MA, K8YSE, KD8CAO, and JN1GKZ last week news of addition contacts
have been received from amateur radio operators worldwide:
+ Henk, PA3GUO uplinked an SSTV signal to the linear transponder and
received the picture on the downlink. He posted a copy of the rec-
cecived image at:
http://www.pa3guo.com/pa3guo_arissat1_sstv_9aug2011_0258utc.jpg
His station configuration was:
Uplink HW: TS2000X, 435MHz, 5W RF power + 12 elements beam
Uplink SW: MMSSTV + HRD (doppler control)
Downlink HW: FunCubeDongle (SDR) + SP-2000 preamp + 2×6 elements
beam
Downlink SW: MMSSTV + DK3WN Satcontrol (doppler/freq control) +
HDSDR
+ Andre, ZS2BK reported a successful two-way CW contact with Pierre,
ZS6A on August 5.
+ Alex, VK5ALX reported a contact with Geoff, VK2ZAZ on August 6.
+ Bruce, VE9QRP was able to access the linear transponder with 40
watts
into a Lindenblad on TX and another omni on receive. Bruce
commented,
“It’s an amazing thrill to work our AMSAT SDX for the first time,
and
my sense is that any VO-52 class station should be able to hear its
downlink.”
+ Luciano, PY5LF had a contact with Roland, PY4ZBZ and recorded it:
145.950 MHz FM Downlink – OPERATIONAL
145.919 MHz CW Beacons – OPERATIONAL
————————————
The CW transmissions include the satellite callsign ID RS01S, select
telemetry, and callsigns of people actively involved with the ARISS
program.
145.920 MHz SSB BPSK-1000 Telemetry – OPERATIONAL
————————————————-
AMSAT needs your telemetry from ARISSat-1/KEDR. Since there are no
“Whole Orbit Data” storage mechanisms onboard ARISSat-1/KEDR, your
submissions are the only way for AMSAT to collect the spacecraft
telemetry and KURSK experiment results.
+ Recorded file ARISSat-1/KEDR and Kursk telemetry CSV files (in the
ARISSatTLM folder) can be sent as an e-mail attachment to:
telemetry@arissattlm.org
+ If you are running ARISSatTLM and receiving the signal “live”
from ARISSat-1/KEDR, please enable the telemetry forwarding option.
+ The latest telemetry can be seen LIVE on your computer or cell
phone at: http://www.arissattlm.org/mobile
Peter Miller, W1AMJ, the Hartford Hobby Radio writer published a
story about the deployment of ARISSat-1 in the Hartford Examiner
newspaper and at: http://tinyurl.com/4yo3l2m (Examiner.com)
NASA Education Office is getting the word out on ARISSat-1 in their
article, “Hammin’ It Up”:
http://www.nasa.gov/audience/foreducators/hammin-it-up_prt.htm
Also, the extensive list of ARISSat-1/KEDR media links in this week’s
ARISS Status Report, in a bulletin below.
[ANS thanks the ARISSat-1/KEDR Team for the above information]
ARISSat-1 batteries decarghing August 13, 2011
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The ARISSat-1 Battery voltage is decreasing each eclipse period. It therefore
is taking longer for the Battery to charge up to 32.5V to allow the switch from
Low Power to High Power when the satellite enters an illumination period.
Kenneth Ransom, N5VHO has plotted the battery min/max for the last 8 days. We
see that the battery voltage is decreasing at a faster rate than expected.
Kenneth’s graph can be found on the arissat1.org site under FAQ
http://www.arissat1.org/v3/index.php?option=com_content&view=section&layout=blog&id=13&Itemid=134
Take advantage of the High Power mode as much as possible over the next few
days.
Virtual Audio Cable software August 11, 2011
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Virtual Audio Cable
Latest version: 4.10
Description
Virtual Audio Cable software allows you to transfer audio (wave) streams between applications and/or devices.
It creates a set of virtual audio devices named “Virtual Cables”, each of them consists of a pair of the waveform input/output devices. Any application can send audio stream to an output side of a cable, and any other application can receive this stream from an input side. All transfers are made digitally, providing NO sound quality loss (a bitperfect streaming).
VAC behavior is similar to “What You Hear” (or “What U Hear”, “Stereo Mix”) feature of Sound Blaster Live! and Audigy cards. But it is only similar, not equivalent. If you simply need a function like “Stereo Mix” under Vista/Win7, there could be better to try to enable it in your audio adapter.
If more than one applications are sending audio to Virtual Cable device, VAC mixes all streams together. If more than one applications are receiving audio from Virtual Cable device, VAC distributes the same audio data among all targets.
VAC is useful to record application’s audio output in real time (audio player, instant messenger or software synthesizer), or transfer a sound stream to another application processing it. You can, for example, use two or more software audio players/generators/synthesizers/sequencers to produce audio streams, sending them to Virtual Cablet device and record a mixed stream from the same Virtual Cable device, using any recording software – Windows Sound Recorder, Audacity, Sound Forge, WaveLab, Adobe Audition (formerly Cool Edit Pro), Gold Wave, Cakewalk/Sonar, Cubase/Nuendo etc.
With an ASIO wrapper like ASIO4ALL from Michael Tippach, you can use VAC in ASIO supporting applications.
If you use an audio encoder application that encodes a stream coming from a sound card, you can use VAC to supply such encoder with a stream produced by other application.
You can use VAC to capture an output sound stream from the application that doesn’t allow to write it into WAV file directly. Unlike Total Recorder allowing you to simply save audio stream, VAC allows to route it in real time.
If you are using some Voice Over IP (VoIP) and/or Internet Telephony applications like Skype, you can use VAC to record your calls and conversations.
VAC needs no hardware audio card; it is a “virtual audio card” itself.
A detailed description is included into a free trial package.
Since VAC 4 is a WDM driver, there are some benefits but some (generally older) applications that use MME (waveIn/waveOut) interface can work better with the older VAC 3 version. This version also supports Windows 98/ME.
If you need to simply share your In/Out wave ports among several applications under Windows 2000 and earlier Windows versions, take a look to the Wave Clone software.
Features
Trial version limitations
Download and purchase
How to install
How to upgrade/downgrade
Support
Release history
Become an affiliate
Source code and other options
Other software from me
Features
Windows XP/2003/Vista/Win7 platforms (32-bit and 64-bit)
Local session only (not available from Remote Desktop).
Native WDM/KS audio technology.
Up 256 Virtual Cables (Windows limits number of MME devices to 32. Number of DirectSound devices is not limited).
1..20 milliseconds per interrupt.
1..100 pin instances.
Almost any of fixed point PCM audio formats (200..1000000 samples per second, 8..32 bits per sample, 1..8 channels). Floating point formats are not supported.
Almost no sound latency with maximal interrupt frequency.
Unlimited number of clients connected to each port.
Signal mixing (with saturation) between output port clients.
PCM format conversion.
Volume control features.
Control Panel application to dynamically configure cables.
Audio Repeater application that transfers from any Wave In to any Wave Out port.
Practical Rotor system August 10, 2011
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A PRACTICAL ROTATOR SYSTEM (APRS)®
APRS SUMMARY: This project is s simple 2 wire interface between the ubiquitous Radio Shack antenna rotator and 2 bits on a parallel port. APRStk.EXE (a version of APRSdos) supports it. I hope other APRS programs might consider it as well. Any rotator which operates on about 30 volts AC and rotates at 1.0 RPM should work as well. Read these instructions ENTIRELY before you start working on your rotator to be sure you understand which rotator you have and which wire is which…
WHY THIS WORKS: For almost all of the Low Earth Orbiting (LEO) amateur satellites a modest beam antenna is more than adequate to bring in signals from the digital packet and voice FM downlinks to your dual band FM radio. This Practical Rotator System can add full automatic antenna control to your PC for under $90. This is a bargain compared to the $750 required for a Kansas City Tracker and Yeasu AZ/EL Rotator system.
The APRS rotator takes advantage of the geometry of low earth orbiting satellites which are within view of a 10 degree fixed elevation beam over 96% of all pass times. In this region, using a short 4 to 6 element beam, your station will be able to maintain over 10 dB of relative gain on the bird whenever it is in view. Low Earth orbits are unique because:
· 4-6 elements are enough gain to be above digital and FM voice thresholds
· Most LEO birds are mostly vertical polarization most of the time.
· LEO satellites are below 45 deg 95% of the time and 6 to 10 dB closer when above it as shown below:
The drawing below shows the Earth and the typical LEO orbit to scale. It is clearly seen, that satellites are rarely “overhead” and spend most of their in-view times well below 30 degrees. Another revealing observation is that when satellites are higher in elevation, they are also 6 to 10 dB closer. This means that for operating LEO satellites, you need maximum gain on the horizon and can get by with minimial gain at high elevations. Angles are shown on the left and percents and path loss are shown on the right.
Now lest superimpose a typical 6 element beam antenna pattern pointed at the horizon on the range and angle plot above. The 6 element beam shows about 10.5 dBi gain towards distant satellites on the horizon which falls off by 3 dB at 30 degrees and by about 7 dB at 45 degrees. This antenna would perform EXCELLENTLY as both a terrestrial and satellite antenna, since almost 85% of all satellite pass times are within the 3 dB beamwidth of the antenna. And the other 15% above 30 degrees are easily 10 dB closer as shown above!
The savy operator will note that still fully half of all satellite passes are below 15 degrees, and this horizontal beam is giving up about 1 dB at 15 degrees. And since ground reflection and usual obstructions block the 0 to 5 degree horizon for most people, then th e best all around fixed elevation antenna should be elevated NO MORE than 15 degrees. As shown below, this results in additional gain for the small time the satellite is above 30 degrees with no sacrifice below 30 degrees. But in no case should the antenna be elevated any further because the loss of gain in the 0 to 15 degree range where satellites spend fully 50% of their time should not be compromised.
The following table is a plot of overall gain for the elevation angles shown. Notice the cumulative percent column showing 96% of all pass times are below 50 degrees. This shows how a beam aimed about 10 to 15 degrees above the horizon will give you maximum gain on the horizon where you need it most, and yet still give you a good signal all the way in closer and higher to overhead. As the gain of the beam drops off at high elevation, that gain is made up by the satellite being much closer. Tilting an antenna any higher than about 15 degrees will sacrifice gain where you need it most, and give you gain where you need it least. Of course, if you cannot see the horizon from your location, then a higher up-tilt makes sense, but then, a smaller antenna probably 3 or 4 elements will do.
EL PCT CUM-% RANGE RNG-GAIN ANT-GAIN OVERALL-GAIN
— — —– —– ——– ——– ————
10 32 32 3030 0 10 10
20 35 67 2440 2 10 12
30 17 84 1827 5 9 14
40 8 92 1460 6 7 13
50 4 96 1190 7 6 13
60 2 98 1020 9 3 12
* Data for an 800 km orbit. For the ISS at 370 km, the times below 30 degrees are 6% higher.
* If your horizon is blocked below 5 degrees anyway, elevate the beam to 20 deg to improve gain (+2 dB)
CONSTRUCTION: The interface is built on a small perf board and placed inside the rotator and accomplishes the following objectives:
1) Adding an ON/OFF switch to select manual or PC controlled operation.
2) Adding ventilation holes to keep the transformer cool. After this mod, the primary of the transformer is always on, so the transformer runs somewhat warmer than normal.
3) Adding the TRIAC’s and optoisolators to interface the PC to the ARCHEROTOR wiring. This circuit uses a special balanced optoisolator design so that there is no chance that the bits on the parallel port can cause both TRIAC’s to switch on at the same time. The rotator goes left or right depending on the polarity of the logic level applied to the two wires.
MODIFICATION PROCEDURES:
The day I finished this set of procedures for the ARCHEROTOR model 15-1225 I went to buy another and now it is a new 15-1245 model. Fortunately electrically they are the same. The 1245 does have better ventilation, but the cover is harder to get off. Differences are noted where they apply.
1) OPEN: Remove the controller top plastic cover by inserting a thin screwdriver in the four slots around the edge and pressing the lower halfshell outward. (New model, remove the screw in the bottom and then insert a knife in either side 1” in from the front or back. When it pops open slightly, work the knife around to the other 4 snaps and it should come off easily).
2) ADD VENTILLATION, BOTTOM: Remove the two screws holding the transformer in place and any tiewraps and lift it out of the way. Using a 1/4″ drill bit or larger, drill 14 holes in obvious places. There would be 4 rows of 4 holes but you do not drill out the mounting posts for the 2 screws you just removed. Also drill a 1/4″ hole in extreme lower right front of the base for our new ON/OFF switch. (New one: drill 4 rows of 4 holes in the transforemer area).
3) ADD VENTILLATION, TOP: In the back and left sides of the top, drill 5 or 6 evenly spaced holes near the transformer. Do NOT louse up the appearance of the top by drilling through the top top.
4) JUMPER AC, ALWAYS ON: There are two black wires to the controller’s switch. One goes to a transformer lug and the other to a wire nut. Jumper between the transformer lug and the wire nut so the AC is always on to the transformer primary. (New model, the wires are black and white. Clip off the crimp-on wire nuts on these TWO wire junctions, tape off the B&W wires (now unused) and join the AC line and other black wire under a new screw-on wire nut. The crimp nut with the surge protector grounded to the Transformer remains untouched.)
5) MOUNT SWITCH:
· Slide back heatshrink covering the connection of the two yellow motor wires and the transformer wire and separate them. Thread the two motor wires over to the top of the left side of our switch. Solder a jumper to extend the yellow transformer wire over to the middle post of the same switch side. (New model. Cut lose the tie-wrap holding all the wires in place. You will find a sleeve over a junction between a RED from the transformer to the two wires (now black and clear) going to the indicator motor.)
· Unsolder the brown wire (which goes to the controller’s manual switch knob) from the transformer and feed it under and around to the top post of the right side of our new ON/OFF switch. Take a new 10″ wire from the middle post of our new switch back to this same post on the transformer. (New model. Its still a brown wire but spliced to a black transformer wire instead of a transformer post )
· Add a new 8″ wire to jumper from the bottom post of our new switch and run it to the “common” connection on the TRIAC board.
6) BUILD TRIAC BOARD according to the sketch and mount under the upper right screw that holds the transformer in place. Solder two short jumpers from the Triac outputs down to the screw terminals #1 and #2 going to the external rotator. Left or right, 1 or 2 doesn’t matter. The circuit is symetrical.)
· Insert the Triacs from the bottom and let pins protrude about 3/16ths inch on the top. Bolt the two Triacs together to let them heatsink each other. Bend the two center pins over each other. This is the TRIAC COMMON point. Insert the two optoisolators taking care to bend out pins#4 so that they can plug into the same perf-board hole as the pin’s #2 on the Triacs. Solder.
· Cut one lead on each resistor to about 3/4″ and bend it over in the shape of a horseshoe. Insert the other end wire through the board such that the horseshoe can be soldered to the gate of the Triac. Route the other lead under the board to the optoisolator’s pin 6 and solder.
· Install the diodes so that the cathodes go off the edge of the board to form a connection loop and then route to the optoisolator pin #1. The anode goes under the board to the pin#2 on the opposite opto-isolator.
7) PC CABLE: Solder the 2 pin connector onto the end of the zip cord and add strength and protection with the two pre-cut pieces of heat shrink tubing. Sorry the first batch are right angle. You may want to flatten a little with a pair of pliers. At least they are gold plated. Thread it through the back of the rotator housing, put the two leads through the ferrite bead and solder to the TRIAC board as bit inputs for right and left. Obviously, you may want to replace my two pins with a real DB-25, but I find the two pins far easier to take in and out of my laptop every morning and evening than fighting all 25 pins of a DB25 when only 2 are used.
8) TESTING: Before replacing the cover, take a 9 volt battery in series with a 560 ohm resistor to test your circuit. Momentarilly connect it one way to the PC leads and then the other. The rotator should rotate one way and then the other.
9) FINISH: Replace top cover. Insert the two-pin plug into the pins 2 and 3 of your parallel printer port LPT-1. Sending a 1 to the port 888 will cause the rotator to go LEFT. Sending a 2 to the port will cause the rotator to go RIGHT. Pins 2 ans 3 are the 2nd and 3rd ones in from the upper right on the top row (the longer row) . If it goes the wrong way, just plug the two pins in the other way.
WARNINGS AND CAUTIONS:
1) Any antenna and rotator system is a natural lightening rod which will attract lightening. Connecting any such device to your computer is risky in the case of a near or direct lightening hit. This circuit has been designed with optoisolators for over 5000 volts of protection of the PC circuit from the AC and antenna circuits; but this will not protect your station or computer from a direct hit. USE AT YOUR OWN RISK.
2) The APRS modifications to this ARCHEROTATOR will keep the transformer primary circuit always connected to 115 volt power no matter what the position of the ON/OFF – AUTO/MANUAL switch. There will be some heat build up in the plastic housing and this must be allowed to escape through the ventilation holes provided in the instructions above. Whenever the rotator is not to be used for an extended period of time, it should be unplugged.
If your rotator is different than 1 RPM, change the constant in the APRStk config file to match your speed. See CFIGK20.APR in your root directory. The value “6” near the end is for 6.0 degrees per sec.
NOTE! The NEW ROTATOR model 15-1245 appears to move at 5.6 deg / sec. Measure yours. You may need to change your CFIG file.
Cosmonauts conclude eventful Russian Stage spacewalk on ISS August 7, 2011
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Cosmonauts conclude eventful Russian Stage spacewalk on ISS
August 3rd, 2011 by Pete Harding
Two Russian cosmonauts have conducted what turned out to be an eventful EVA outside of the International Space Station (ISS) on Wednesday, as part of the ongoing Expedition 28. Going by the designation of RS (Russian Segment) EVA-29 (Extra Vehicular Activity-29), the excursion’s timeline had to be reorganized, resulting in the loss of a major three hour Strela task, now moved to a future EVA.
Expedition 28 EVA:
Russian cosmonauts Sergei Volkov and Alexander Samokutyaev are the crewmembers who conducted the spacewalk. Volkov, completed the third spacewalk of his career having previously conducted two spacewalks in 2008, was designated EV-1, and Samokutyaev, who was making his first ever spacewalk, was designated EV-2. Both Volkov and Samokutyaev sported the Russian Orlan-MK spacesuits marked with blue stripes.
Once the hatch of the Docking Compartment-1 (DC-1) “Pirs” was opened at 2:50 PM GMT, Volkov and Samokutyaev egressed the station to begin 5 hours and 57 minutes of scheduled tasks.
See Also
LIVE Stage EVA Updates
L2 ISS Section
L2 Russian Section
Click here to Join L2
The first order of business for Volkov and Samokutyaev was to deploy a free-flying satellite. Known by the names of ARISSat-1 and Radioskaf-V, the 57 pound satellite was built using off-the-shelf components by Radio Amateur Satellite Corporation (AMSAT), the NASA Office of Education ISS National Lab Project, the Amateur Radio on ISS (ARISS) working group, and RSC-Energia.
It is designed as a prototype for a series of similar satellites that will carry up to four student experiments and transmit their data back to Earth via amateur radio. ARISSat-1 only carries one student experiment however – an atmospheric pressure sensor built at Kursk University in Russia.
Additionally though, in order to mark the 50th anniversary of Yuri Gagarin’s spaceflight, it will transmit via amateur radio commemorative audio messages in 50 different languages, and still-frame Earth views from four onboard cameras.
Launched to the ISS aboard Progress M-09M/41P on January 28th, ARISSat-1 was originally scheduled for deployment during RS EVA-28 on February 16th, so that it could broadcast the commemorative messages during the 50th anniversary of Yuri Gagarin’s launch on April 12th.
However, analysis showed that if it were deployed on EVA-28, then the satellite’s batteries would have depleted before April 12th, and so the decision was made not to deploy the satellite during EVA-28, but instead to briefly turn the satellite on inside the ISS on April 12th so that it could transmit its commemorative messages.
During the EVA, the satellite was manually jettisoned in a retrograde (aft) direction from the ISS, so that it will not pose a debris threat in the future. The satellite will eventually run out of power and burn up in Earth’s atmosphere.
This was supposed to be the first task of the spacewalk. However, after noticing only one – instead of two – antennas on the device, controllers asked to defer the task until later in the EVA to check the configuration.
After confirming one antenna was missing, controllers decided to press ahead and deploy the satellite, which was confirmed at 1:43pm Central time. There will be a 50 percent loss in performance due to the missing antenna.
Prior to this later-than-scheduled deploy, Volkov and Samokutyaev moved on to their second task – the installation of the BTLS-N (Onboard Laser Communications Terminal) monoblock experiment to the portable multipurpose workstation on the Starboard side (plane IV) of the Service Module (SM) Work Compartment (RO) large diameter section.
The BLTS-N will test high-speed test laser-based communications between ISS experiments and Earth at speeds of up to one-hundred megabytes per second.
The spacewalkers were also tasked with the removal of the AO-VKA antenna from the SM RO small diameter section. The AO-VKA antenna was used during the Mini Research Module-2 (MRM-2) “Poisk” docking in November 2009, but is no longer needed and so will be brought back inside the ISS.
Also completed by the spacewalkers was the photography of the WAL6 antenna of the Proximity Communications Equipment (PCE) antenna feeder unit on SM RO small diameter section.
The WAL6 antenna has been showing signs of degraded performance, and so the imagery will be used by engineers on the ground to determine the condition of the antenna and potentially determine a root cause.
Due to the problems with ARISSat-1′s delayed deployment, the major objective of the EVA – the three-hour relocation of the Strela-1 crane from DC-1 to MRM-2 – was cancelled from the EVA.
The two Strela cranes on the ISS are designed to move large components around outside the Russian Segment of the ISS. Their telescopic boom design allows them to extend, and they can be pointed toward a desired location by an astronaut controlling it from outside the station.
Both Strela cranes have been located on DC-1, with Strela-1 on the Starboard side and Strela-2 on the Port side.
The Strela relocation is required since DC-1 will need to be undocked from the ISS and disposed of in late 2012/early 2013 in order to free up the SM Nadir docking port for the arrival of the Russian Multipurpose Laboratory Module (MLM).
Since the Strela cranes will be useful throughout the lifetime of the ISS, they must find a new home before DC-1 is disposed of.
The task – which will now take place on a later stage EVA – will involve the use of the Strela-2 crane, which will remain at its current location on DC-1 for now. After a special post is installed onto the end of Strela-2 (at a 90 degree angle to the boom), Strela-2 will be pointed at Strela-1, and the post will grapple Strela-1.
Once Strela-1 is detached from DC-1, Strela-2 will maneuver Strela-1 to the Port side of MRM-2 (which is right above Strela-2) using its telescopic ability. Strela-1 will then be installed onto MRM-2 and ungrappled from Strela-2.
With this major task cancelled, Volkov and Samokutyaev briefly returned to DC-1 to retrieve the Biorisk-MSN experiment, which will then be installed onto a handrail outside DC-1.
The Biorisk experiment will investigate the effects of bacteria and fungus on materials used in spacecraft construction, and how solar activity may affect the growth of such microbes.
The final tasks of the spacewalk saw Volkov and Samokutyaev photograph the SKK #1 materials exposure container on MRM-2, and the Komplast panel #11 on the Functional Cargo Block (FGB).
Another task carried out was the photography of a set of pictures showing influential Russian space figures Yuri Gagarin, Sergei Korolev, and Konstantin Tsiolkovski floating in the vacuum of space.
Once those tasks had been completed, Volkov and Samokutyaev headed back inside DC-1 to conclude the six hours, 23 minutes EVA, with ingress and hatch closure marked at 9:19 pm GMT (4:19 pm Central).
For the duration of the EVA, ISS Commander Andrey Borisenko and Flight Engineer-3 (FE-3) Ron Garan were isolated inside MRM-2, to which their Soyuz TMA-21/26S spacecraft is docked.
FE-6 Mike Fossum and FE-5 Satoshi Furukawa had access to every part of the station that is forward of the SM, since their Soyuz TMA-02M/27S spacecraft is docked at MRM-1, which in turn is located at the FGB Nadir port.
This “lockout” was necessary since all hatches leading to the SM Transfer Compartment (PKhO), to which DC-1, MRM-2 and the FGB are docked, must remain closed so that the PKhO can be used as a back-up airlock in the event that DC-1 cannot be repressurised.
However, per ISS flight rules, all crewmembers inside the ISS must have access to their Soyuz spacecraft in case an emergency occurs, and so all crewmembers must be on the same side of the hatch as their respective Soyuz spacecraft.
The next spacewalk (RS EVA-30) is currently scheduled to be conducted sometime in February 2012 – meaning that this EVA will be the last scheduled EVA of 2011, and the last scheduled EVA for six months.
Click here for ISS news articles: http://www.nasaspaceflight.com/tag/iss/
With the Space Shuttle now retired, the tempo of spacewalk activity is expected to decrease markedly, with two or three Russian spacewalks, and only one US spacewalk being conducted annually.
Tasks previously conducted by US spacewalkers will now be conducted robotically by the Special Purpose Dextrous Manipulator (SPDM) “Dextre” – which itself is set to conduct a series of complex tasks in the coming weeks, which will be covered in a future article here on NASASpaceflight.com.
(Images: Via L2 presentations and NASA.gov. As with all recent missions, L2 is providing full exclusive level mission coverage, available no where else on the internet.
(To join L2, click here: http://www.nasaspaceflight.com/l2/)
Tags: EVA, ISS, Russian
This article was published on Wednesday, August 3rd, 2011 at 8:35 am and is filed under Featured, Other, Russian.
August 7, 2011
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http://www.youtube.com/user/NASAtelevision
How to receive ARISSat-1 August 7, 2011
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Following the successful tests last weekend, the latest Amateur Radio satellite ARISSat-1 will be deployed from the ISS today, August 3, during a space walk that commences at 1400 GMT.
AMSAT-NA have created a special page with information on how to receive the satellite.
ARISSat-1 can transmit Slow Scan TV pictures from its 4 onboard cameras and it is hoped a picture of the actual deployment wil be transmitted. The SSTV FM signal should be receivable using simple equipment such as a 2m FM handheld with a quater wave whip. ARISSat-1 also has CW and BPSK beacons and a cross band 435/145 MHz linear transponder for SSB/CW working.
Read the new AMSAT-NA guide – ARISSat How To: Operating Tips, Pointers, Downloads
http://www.amsat.org/amsat-new/ARISSat/ARISSatHowTo.php
You can watch the deployment of ARISSat-1 live on NASA TV, coverage starts at 1400 GMT (1500 BST)
http://www.nasa.gov/ntv
It is believed the first pass receivable in the British Isles will be
23:46:34 GMT on August 3.
Online Satellite Pass Predictions, select ARISSat-1
http://www.amsat.org/amsat-new/tools/predict/
Read the ARISSat-1 article from QST at
http://web.me.com/clintbradford/Work-Sat/
ARISSat-1_files/QST-ARISSat1.pdf
Follow ARISSat-1 on Twitter:
http://twitter.com/#!/arissat1
In USA you can also text ‘follow Arissat1′ to 40404 with your cell phone. (leave off the quotes).
Free Slow Scan TV Software MMSSTV uses your PCs Soundcard
http://mmhamsoft.amateur-radio.ca/
IZ8BLY Vox Recoder, enables you to record the signals from the
ARISSat-1 on 145.950 MHz FM while you’re at work
http://antoninoporcino.xoom.it/VoxRecorder/
The latest telemetry can be seen live on your computer or cell phone at http://www.arissattlm.org/mobile
Download the Windows and Mac versions of the ARISSatTLM free ground station soundcard demodulator and display software:
http://www.arissattlm.org/
The ARISSatTLM software user guide is available:
http://tinyurl.com/42uhtyf (amsat.org)
Get your color ARISSat-1 Frequency Guide:
http://tinyurl.com/4t497t2 (amsat.org)
AMSAT-UK publishes a colour A4 newsletter, OSCAR News, which is full of Amateur Satellite information.
Join online at http://tinyurl.com/JoinAMSAT-UK
A sample edition of the newsletter can be seen at
http://www.uk.amsat.org/on_193_final.pdf
Life Expectancy ARISSat-1 August 7, 2011
Posted by iz4fvw in Uncategorized.add a comment
from From: Phil Karn
Well, an educated guess can be made by looking at a plot of ISS altitude
vs time:
http://www.heavens-above.com/IssHeight.aspx
The ISS is periodically reboosted, accounting for the sudden jumps in
this sawtooth-like graph. Obviously ARISSat-1 won’t be reboosted, so if
you extrapolate the downward-sloping parts of the graph you can get a
rough idea of what will happen.
The ISS orbital decay rate varies with changes in upper atmospheric
density with solar activity, but also because of changes in its attitude
and the operation of the solar panels.
The orbital decay rate also depends on qthe ballistic coefficient of the
object. This has units of mass divided by area — the mass of the object
divided by the cross-sectional area it presents in its direction of
flight. The larger the ballistic coefficient, the less its deceleration
from drag as it flies through the thin upper atmosphere.
The ISS probably has a larger ballistic coefficient than any other
satellite simply because it’s so huge. The volume of most objects
increases as the cube of the size while the cross-sectional area
increases with the square. Since mass is usually a function of volume, a
large object will generally have a higher ballistic coefficient and last
longer in a given orbit than a small object.
Obviously there are exceptions to the “large lives longer” rule such as
the “Echo” balloons. The actual ballistic coefficient for any given
satellite has to be computed from its actual mass and dimensions and its
orientation relative to its velocity vector. The ISS is a huge
satellite, but it also has lightweight solar wings that greatly increase
its cross-sectional area without increasing its mass very much, so they
decrease its ballistic coefficient somewhat.
ARISSat-1 is far smaller than the ISS, but it is fairly heavy for its
size and it lacks large solar wings that create a lot of drag. This will
reduce its decay rate, but it will still probably decay more quickly
than the ISS.
It was tossed out the back of the ISS against the velocity vector, and
that immediately put it in a lower energy orbit with a higher mean
motion. But any further increase in mean motion will be due to orbital
decay, and from that we should be able to estimate its ballistic
coefficient and how it will likely behave in the future. Determining an
exact lifetime would be difficult because of the difficulty of
predicting solar activity, but a good estimate can probably be made.
How to receive ARISSat-1 August 7, 2011
Posted by iz4fvw in Uncategorized.add a comment
Certificates are available to anyone that receives the voice, digital or Morse code signals signals from ARISSat-1.
Voice and SSTV signals can be heard using just a 2m FM amateur radio receiver tuned to 145.950 MHz.
These are transmitted continuously in a round robin format:
Voice ID
Greeting
Voice Telemetry
Voice ID
SSTV image
A Secret word/password is included in most greetings.
Email the secret word/password, your name or group, date/time received,city, state, country and your email address to secretword@arissat1.org to receive a certificate.
The Voice Telemetry comprises selected telemetry channels read in a female voice.
Tone introduction – alerts you that telemetry data is to follow
MET is xxxxx – Mission Elasped Time in minutes
IHU Temp is -xxx degrees C
Control Panel Temp is -xxx degrees C
Battery Voltage is xx.x Volts
Battery Current is -xxx milliAmps
Email the voice telemetry data, your name or group, date/time received,city, state, country and your email address to
tlmreport@arissat1.org to receive a certificate.
The Slow Scan TV (SSTV) images are sent in Robot-36 format. Email a description of the SSTV image received, your name or group, date/time received,city, state, country and your email address to sstvreport@arissat1.org to receive a certificate.
Further information on the transmissions and certificate is available at
http://www.arissat1.org/v3/index.php?option=com_content
&view=category&layout=blog&id=61&Itemid=137
How to receive ARISSat-1
http://www.southgatearc.org/news/august2011/
how_to_receive_arissat1.htm
ARISSat How To: Operating Tips, Pointers, Downloads August 2, 2011
Posted by iz4fvw in Uncategorized.add a comment
From AMSAT-NA website:
ARISSat How To: Operating Tips, Pointers, Downloads
Radio-to-Soundcard Interface For Access to ARISSat-1/KEDR Bandwidth
(Thank you to Christophe Mercier, ARISS-Europe for the French translation of the ARISSat-1/KEDR description, ARISSatTLM Software Guide, Color Frequency Guide.)
The ARISSat-1/KEDR FM downlink on 145.950 MHz will be audible on all common 2 meter amateur radio receivers with no modification needed to your equipment. A CW/SSB receiver will also receive the CW beacons on 145.919 MHz or 145.939 MHz and the signals on the linear transponder passband between 145.922 to 145.938 MHz.
You can see the relationship of all of the ARISSat-1/KEDR frequencies with this color frequency guide.
To take advantage of the full bandwidth of the downlink for SSTV, CW Decoding, BPSK Decoding you’ll need to add a few things:
You’ll need an audio patch cable from your receiver to your computer soundcard audio input. If you are already on the air with other amateur radio soundcard applications then you are ready with the hardware to receive, decode, and display the SSTV, BPSK-1000 or BPSK-400 downlinks.
You’ll need SSTV software (refer to the SSTV news item)
You’ll need the ARISSatTLM software to decode the BPSK telemetry.
The key difference is that the SSTV signal is transmitted on the FM downlink on 145.950 MHz. The BPSK-1000 downlink is transmitted in SSB mode on 145.920 MHz. Depending on your equipment you may need to fabricate an audio patch to the computer soundcard input from both your 2 meter FM radio and 2 meter SSB radio.
An initial RECEIVE ONLY configuration is easily done consisting of an audio patch cable between your radio and the soundcard. The ARISSat-1/KEDR team testing the software noted that a minimal set up consisting of an audio cable from the speaker or headphone output from the radio to the line (or mic) input on your PC sound card was successful. If your rig has a ‘Line Out’ audio connection this can be run to the soundcard ‘Line In’ connection.
Many amateur radio “digital modes” articles, web pages, and books also discuss the more complex requirements to interface your transmitter to the soundcard and to control the push-to-talk functions. This is NOT required for you to successfully receive, decode, and display the signals you receive from ARISSat-1/KEDR. To join into the all the fun your RECEIVE ONLY configuration will just need the audio cable!
How To Receive the ARISSat-1/KEDR BPSK-1000 Telemetry
The BPSK transmission from ARISSat-1/KEDR will feature a new 1kBPSK protocol developed by Phil Karn, KA9Q to be readable in low signal level conditions. The BPSK data will transmit satellite telemetry and data from the Kursk experiment.
You’ll need to take a few steps to get your station set up to receive, decode, and display the BPSK-1000 telemetry data:
You need a 2 meter SSB receiver.
An audio patch cable between your receiver and computer’s soundcard is required.
Download the ARISSatTLM ground station soundcard demodulator and display software. Windows and Mac versions are available.
Follow the instructions in the ARISSatTLM Software Quick Start Guide to install the software.
The ARISSatTLM software can decode BPSK signals in two modes:
Playback and decode a recorded file (even if you do not have a 2 meter SSB receiver you can experiment with the software and test file to learn about telemetry decoding and display!)
Live, off-the-air capture
Playback and Decode a Recorded File
ARISSatTLM requires the recorded data to be in the WAV format. Compression formats such as MP3 are not suitable and will not decode and display correctly. Although .WAV files are notably
large, usually several megabytes, they capture all of the bits of the signal. Compressed file formats sound OK to the human ear but save file space by eliminating bits from the recorded
stream. You need to capture and record as many of the downlink bits as possible. An occasional noise burst or momentary fade is handled by the Forward Error Correction capability of the ARISSatTLM software.
Download the BPSK Test File
A link to a BPSK test file suitable for operation with the current release of ARISSatTLM software will be released soon to http://www.arissattlm.org.
NOTE: Some earlier BPSK test recordings that are on the internet will not work with the currently released software because they were created with earlier versions of the satellite’s onboard software (the satellite software and ARISSatTLM are a “matched pair”).
Start the ARISSatTLM program on your computer.
Click the start button in the lower left of the Tuning Indicator window.
In the ARISSatTLM Version 0.50 Window select: File –> Open WAVE file. Select the ARISSatTLM test file you previously downloaded.
The Tuning Indicator window will show the “CW Bump” at proper location (note the “Put CW signal here” indicator).
The Morse Code Decoder will decode and stream the CW message.
The ARISSatTLM Telemetry as Text window will decode and display data.
The ARISSatTLM window will display the received data as received.
The display will stop when the end of file is reached.
Live Off The Air Telemetry Capture and Display
The ARISSat-1 BPSK-1000 downlink is transmitted in SSB mode on 145.920 MHz. When the CW2 beacon on 145.919 MHz is active this indicates that the BPSK-1000 format is being transmitted. If the CW1 beacon on 145.939 MHz is active this indicates the backup of BPSK-400 format is being transmitted.
Transmitting at 100 mW, both BPSK rates include Forward Error Correction (FEC) and it is expected that modest quarter-wave antennas with low-loss coaxial cable will provide sufficient signal strength for decoding and display by the ARISSatTLM software.
BPSK-1000 sounds like a “shusssch” with a higher pitch than the 400 bps growl. It is difficult to tune by ear. The BPSK beacon is centered 1 kHz above the CW2 beacon so that the CW beacon sits in the lower spectral null of the BPSK signal, i.e., in a narrow spot where there’s no BPSK signal power.
If you put your receiver in USB mode and tune the CW beacon so it comes out at an audio frequency of 500 Hz, this will automatically center the BPSK signal in a conventional SSB filter extending from 300-2700 Hz. The Tuning Indicator window helps you tune the signal correctly.
Follow the recommendations in the ARISSatTLM Quick Start Guide for tuning and decoding the BPSK telemetry data. Once you are tuned in correctly (and adjust for doppler shift) you will be able to decode the BPSK-1000 signal. You will also be able to copy the CW2 beacon text in the Morse Code Decoder window.
AMSAT needs your telemetry from ARISSat-1/KEDR. Since there are no “Whole Orbit Data” storage mechanisms onboard ARISSat-1/KEDR, your submissions are the only way for AMSAT to collect the spacecraft telemetry and KURSK experiment results.
The telemetry may be recorded using the FunCube dongle or SDR-IQ receivers. After decoding the recorded file ARISSat-1/KEDR and Kursk telemetry CSV files (in the ARISSatTLM folder) can be sent as an e-mail attachment to telemetry@arissattlm.org
If you are running ARISSatTLM and receiving the signal “live” from ARISSat-1/KEDR, please enable the telemetry forwarding option.
The latest telemetry can be seen LIVE on your computer or cell phone.
How To Receive the ARISSat-1/KEDR SSTV Signal
The ARISSat-1 FM downlink on 145.950 MHz includes live SSTV images as part of the cycling voice ID, select spoken telemetry values, and the international greeting messages. Here are some pointers to help you get your station ready to receive and display the SSTV pictures transmitted by ARISSat-1.
One fun feature is that there are four SSTV cameras mounted on the spacecraft. On photos of ARISSat-1 you may have noticed black brackets on the outside of the spacecraft. These hold the mirrors that reflect the light onto the lens of the cameras. The software-defined-transponder will use the image data from the cameras to generate the SSTV downlink.
ARISSat’s software will sequentially select a new or stored image from one the four cameras. There are two pre-recorded images as part of the sequence. The camera that took the the picture can be identified by the color of the call sign in the upper left of the SSTV image. The SSTV image will be sent down as FM audio SSTV in Robot 36 format on 145.950 MHz about every 140 seconds.
The RF downlink power on the 145.950 MHz FM downlink will be 250mW which is predicted to provide a link margin around 6 dB on an HT with a ‘big whip’ when the satellite is at 15 degrees elevation. This should be sufficient to receive SSTV pictures although you may need to orient the whip to line up the antenna polarization.
ARISSat-1 is not stabilized so the antenna orientation is unpredictable and a certain amount of fading will happen. The receiving link margin may be improved with a handheld beam such as a commercially available “Arrow”, “Elk” antenna., The WA5VJB “Cheap Yagi” antenna web pages document how you can build your own.
See the news bulletin regarding tips and pointers for the audio interface between your radio and your computer’s sound card. When running your SSTV software just adjust the sound card audio gain slider and/or radio volume control so that the SSTV signal is within the center part of the bar. MMSSTV will give you an “overflow” indication if the volume is too high.
SSTV Software Download Sites
There are many amateur radio SSTV software decoding applications available. One of the easiest to use on Windows computers is the MMSSTV program.
The Ham Radio Deluxe software package also includes SSTV operation.
MultiScan SSTV software for the Mac.
If you successfully receive the SSTV transmissions, you are invited to upload your picture to to the ARISS SSTV Gallery.
