Date: Thu, 7 Apr 94 04:30:14 PDT
From: Ham-Space Mailing List and Newsgroup <ham-space@ucsd.edu>
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Subject: Ham-Space Digest V94 #84
To: Ham-Space
Ham-Space Digest Thu, 7 Apr 94 Volume 94 : Issue 84
Today's Topics:
Az/El Rotator suggestions wanted
best 2m lin/circ antenna
Motorola GPS engine group purchase update
Satellite Forum Schedule at Dayton?
SPACE STATION SYSTEM DESIGN REVIEW COMPLETED
Wanted: 2m/70cm Satellite Antennas
Send Replies or notes for publication to: <Ham-Space@UCSD.Edu>
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We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: 6 Apr 94 14:28:23 CDT
From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!vixen.cso.uiuc.edu!uchinews!cdsmail!timbuk.cray.com!walter.cray.com!ned.cray.com!cbetz@network.ucsd.edu
Subject: Az/El Rotator suggestions wanted
To: ham-space@ucsd.edu
In article <2nq3uj$4rf@crchh7b0.bnr.ca>, debaker@bnr.ca (David Baker) writes:
>
> Hello,
>
> I am looking for suggestions on homebrewed or inexpensive az/el
> combos. I have looked at the kilobuck stuff from Yeasu and similiar
> makers, but am wondering if there are any kits or ideas for cheaper
> construction. I have read just about every satellite publication,
> so I have already seen a lot. I am trying to identify any designs
> that use inexpensive rotators (like the R/S TV rotator), and gear
> them down and perhaps modify them for greater than 360 degree rotation
> in order to get better weight loading and granularity in adjustment.
> If anyone knows of any ideas or plans (or knows about the R/S rotator),
> please let me know.
>
In general, the elevation mechanism is *difficult* part. If you are willing
to do some metal work, you can provide elevation with an actuator arm from
a satellite tv dish. Most of these will lift a pretty fair load, but if the
array is well balanced, it really doesn't have to lift much at all. You
can find these things brand new for as little as $59 (for an 18" arm). If
you are willing to go with used stuff, you can probably find them for alot
less. If you can find the right tvro dealer, you might be able to get an
older used model for free. (One dealer up here told me they just toss them
in the garbage. Of course when I told them I was interested they wanted $50).
If you are interested in this method, there is one such setup described in
the "SPACE COMMUNICATIONS" section of the newer ARRL handbooks (I think since
at least 1991).
The two main disadvantages of this method are you are limited to about 90
degrees or so of elevation, and you will also probably have to build your
own position readout system. This method of course will require that you
build your own mount. It's not quite as simple as sliding a mast through
the rotor, but it can be done alot cheaper.
Charlie Betz N0AKC
Cray Research, Inc. Chippewa Falls, WI
------------------------------
Date: Wed, 6 Apr 1994 14:47:14
From: ihnp4.ucsd.edu!swrinde!gatech!newsxfer.itd.umich.edu!jobone!lynx.unm.edu!dns1.NMSU.Edu!pc-thooker.psl.nmsu.edu!thooker@network.ucsd.edu
Subject: best 2m lin/circ antenna
To: ham-space@ucsd.edu
I am looking to buy a very hi quality, 2m beam antenna. I would like
something better than Cushcraft. I will be purchasing a crossed YAGI, but
desire to operate only one polarization at a time, ie horizontal (for ssb) or
vertical (for FM). Bandwidth needs to be entire 2m band.
I will need to remove the matching / phasing network and use to feedlines,
feeding one set of elements at a time to achieve linear pol.
I have got price quotes on M squared and KLM antennas, but I have never seen
the actual mechanical construction used in these brands. My QTH is in a high
wind envionment, and I desire to have the connections to the elements enclosed
(as I believe the M squared is).
Any info will be appreciated.
T. Hooker email: Thooker@PSL.NMSU.EDU
KA5ECS
------------------------------
Date: Wed, 6 Apr 94 20:33:48 -0500
From: ihnp4.ucsd.edu!swrinde!gatech!howland.reston.ans.net!noc.near.net!news.delphi.com!usenet@network.ucsd.edu
Subject: Motorola GPS engine group purchase update
To: ham-space@ucsd.edu
I just wanted to add my name to the list of people interested in the GPS
module purchase. The final price quote will determine if I am in or out, but
if the estimated per unit price for the 100 lot is correct it should not be
a problem.
Thanks, Dave WA3YDZ
hartrum@delphi.com
------------------------------
Date: Thu, 7 Apr 1994 02:17:16 GMT
From: ihnp4.ucsd.edu!galaxy.ucr.edu!library.ucla.edu!europa.eng.gtefsd.com!news.umbc.edu!eff!news.kei.com!world!eac@network.ucsd.edu
Subject: Satellite Forum Schedule at Dayton?
To: ham-space@ucsd.edu
Hello All,
Does anyone know when the satellite forum(s) will be at Dayton?
73 Eric eac@world.std.com
------------------------------
Date: 6 Apr 94 16:17:59 GMT
From: news-mail-gateway@ucsd.edu
Subject: SPACE STATION SYSTEM DESIGN REVIEW COMPLETED
To: ham-space@ucsd.edu
SPACE STATION SYSTEM DESIGN REVIEW COMPLETED
Mark Hess
Headquarters, Washington, D.C.
March 24, 1994
Kari Fluegel
Johnson Space Center, Houston
RELEASE: 94-53
Plans for the International Space Station are maturing rapidly and the
orbiting research facility is on track for assembly to begin in 1997 as
scheduled, program managers said today after completion of the system design
review.
"This was a major milestone for the International Space Station," said
Space Station Director Wilbur Trafton. "The space station team has just
conducted a comprehensive review of the requirements, configuration and the
maturity of the station's technical definition. We now have a solid baseline
for the program. We have an executable schedule with costs that maintain
acceptable reserves within our budget cap."
A major milestone in the space station program, the system design
review (SDR), included participants from NASA, the Canadian Space Agency, the
European Space Agency, the Italian Space Agency, the Japanese Space Agency, the
Russian Space Agency, the prime contractor Boeing and Tier I subcontractors
Rocketdyne and McDonnell Douglas.
Managers reviewed and evaluated the overall configuration, technical
requirements and detailed specifications for the space station during the
meeting which concluded Wednesday at the Johnson Space Center.
"I'm extremely pleased with the results of this program review," said
Program Manager Randy Brinkley. "The results of the SDR demonstrate that the
International Space Station has a high degree of design maturity. This program
is right on track to providing the science community with a world class
orbiting laboratory."
The SDR resulted in a consensus among program managers on the technical
validity of the design and completeness of the station's system specifications,
the operations concept and requirements for interfaces with the Space Shuttle
and Russian launch vehicles. Refinements to cost and program schedules also
were presented.
Baseline Configuration
Using approximately 75 percent of Space Station Freedom hardware, the
completed International Space Station consists of U.S. elements including the
integrated truss, habitation module and laboratory module; the Russian science
power platform, service module and functional cargo block vehicle (FGB); the
ESA laboratory module; Japanese experiment module and exposed facility and the
Canadian remote manipulator system.
The station will operate at an altitude of approximately 240 n.m. (444
km) and will orbit in a 51.6 degree inclination which will offer better Earth
observation opportunities. The International Space Station increases crew size
from four to six. It will have 33 standard user racks for science operations.
Schedule
The planned assembly of the station will begin with launch of the
Russian "FGB" vehicle in November 1997. A docking compartment will be added
before the first American launch in December 1997. The Russian service module
will be added to the station in January 1998 followed by the universal docking
module and the science power platform. The U.S. laboratory module will be
launched on the third U.S. flight in May 1998 and will signal the beginning of
human-tended science operations.
The Canadian-built robotic arm will be launched on the next flight in
June 1998 and the addition of the Soyuz transfer vehicle in August 1998 will
provide capabilities for extended on-orbit operations. The Japanese experiment
module will be launched in early 2000 and the ESA laboratory module will be
added in June 2001. Assembly will be complete in June 2002. In total, the
sequence provides for 13 Russian assembly flights and 16 U.S. assembly flights.
Use of the Ariane V launcher to lift the European module to the station also
has been added to the technical baseline.
Cost
The U.S. contribution to the station is estimated to cost $17.4 billion
from Fiscal Year 1994 until assembly is complete in 2002. This includes annual
budget appropriations of about $2.1 billion and consists of development,
vehicle and ground operations costs and utilization support during the assembly
period.
International Partner Status
Canada completed the critical design review for the Space Station
remote manipulator system in 1993. Changes in the subsystem design requirement
and assembly sequence currently are being addressed.
The critical design review for the Japanese experiment module is
scheduled for 1996. Currently all development activities are on track for
launch in early 2000. The European attached pressurized module (APM)
preliminary design review is scheduled for 1996 with the critical design review
scheduled for 1998. Program managers also are investigating the feasibility of
launching the APM on an Ariane V booster as a baseline.
The inter-government agreements for the station currently are being
amended to include Russia as a full partner. The memorandum of understanding
and joint management plan with Russia will be completed in mid-1994 and
negotiation of a fixed price contract is currently in work.
Extravehicular Activities
The amount of extravehicular activity (EVA) in the critical path for
station assembly has been significantly reduced. EVA crew hours for
maintenance during the station's 10-year operational lifetime also have been
significantly reduced.
Ground Control
The ground system for the International Space Station builds on the
interfaces for the Shuttle and Freedom programs. The design is being optimized
to reduce developmental and recurring costs. All drivers for the ground
control systems are well understood and the final specification will be
baselined for May.
Station systems
All station systems have a high degree of design maturity. For
example, the guidance, navigation and control system design is 97 percent
complete. The communications and tracking system design is very mature and
analysis and testing to date show that all station requirements will be met.
The critical design reviews for the audio, video, S-band and Ku- band systems
have been completed with more than 90 percent of the flight material on order
or available inhouse. The thermal control system has been significantly
simplified. The external active thermal control system has the most
significant changes but still retains 40-50 percent of the previous hardware
designs.
The internal active thermal control system retains 80-90 percent and
the photovoltaic active thermal control system retains 100 percent of the
existing hardware design. Also, analysis shows that designs for the life
support systems also are progressing well with development programs completed
for all major subsystems. A number of key environmental system tests have been
completed using prototype hardware and 90 percent of the hardware has passed a
critical design review.
Transition Activities
Since the transition activities began last fall, 1,050 open issues from
the Freedom program have been resolved. Another 471 new program issues also
have been closed during that time. At the close of the SDR, only 17 issues
remain open. Those issues include providing for additional on-orbit payload
storage, addressing Japanese experiment module and ESA module ventilation noise
levels and determining the location and specifications for an optical quality
window in the station design.
"We've closed nearly 100 issues for every technical issue still to be
resolved and for the few remaining open items, each has a plan on how to close
it and a timetable within which it will be closed," Trafton said. "The team is
tackling the tough issues, making decisions and moving ahead with a space
station that can be built on schedule and at the cost which the Administration
and the Congress have established for this program."
With the completion of the SDR, the space station team will refine the
design to more detailed levels. In April 1995, the program will conduct the
critical design review for the station, a milestone that means the detailed
engineering design essentially will be complete.
"We have come a long way in a short amount of time, and that is due to
an unbelievable level of professional dedication and hard work by all the
program team members," Brinkley said. "Because of these people, the
International Space Station will be on orbit and performing valuable science as
the nation and the world enters the next century."
---
73's de Ed.
@@@ @@@ @@@@@ Eduardo Sweet Biro | postmaster@asarin.org.ar
@ @ @ @ @ |
@@@@@ @@@@@ @ Informatics department director | A mind stretched by a new
@ @ @ @ @ Argentine Inventors Association | idea can never go back to
@ @ @ @ @@@@@ <aai@asarin.org.ar> | its original dimensions.
------------------------------
Date: 6 Apr 1994 16:21:16 -0500
From: ihnp4.ucsd.edu!swrinde!gatech!howland.reston.ans.net!torn!nott!bnrgate!corpgate!crchh327.bnr.ca!debaker@network.ucsd.edu
Subject: Wanted: 2m/70cm Satellite Antennas
To: ham-space@ucsd.edu
Hello,
I have been looking into satellite antennas, and it seems that KLM is
the brand of choice...I am interested in hearing from anyone who has
a KLM for sale. All four models (14C, 18C, 22C, 40CX) are of interest.
If you have another brand of satellite antenna for sale, let me know
anyway... A good value is not to be passed up.
Thanks,
______________________________________________________________________
| David E. Baker | Internet: debaker@bnr.ca (Richardson, TX, USA) |
| IP: 47.122.65.7 | UnixID: crchh7b0 | Bell-Northern Research, Inc. |
| Callsign: AB5PI | Packet: AB5PI@N5AUX.#DFW.TX.USA.NA | Smile! ;-) |
| My opinions do not necessarily reflect the opinions of my employer |
|--------------------------------------------------------------------|
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End of Ham-Space Digest V94 #84
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