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Software Vault: The Diamond Collection
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The Diamond Collection (Software Vault)(Digital Impact).ISO
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spc0220.zip
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SPC0220.TXT
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1995-02-25
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SB NEWS @ AMSAT $SPC0220
* SpaceNews 20-Feb-95 *
BID: $SPC0220
=========
SpaceNews
=========
MONDAY FEBRUARY 20, 1995
SpaceNews originates at KD2BD in Wall Township, New Jersey, USA. It is
published every week and is made available for unlimited free distribution.
* PHASE 3-D NEWS *
==================
On February 13, 1995, the AMST Phase 3D integration facility in Orlando,
Florida was visited by the USA NETWORK television show, "INSIDE SPACE".
Among those interviewed were Keith Baker, KB1SF, Executive Vice President
of AMSAT-NA, Dick Jansson, WD4FAB, Vice President of Engineering for
AMSAT-NA, and Chuck Hennessey, W4AT, Integration Team Member. Also
included were Philip Chien, KC4YER, and David Jordon, AA4KN.
The interviews discussed the AMSAT organization as a whole, its past
accomplishments, and future endeavors in addition to a detailed tour of
the Phase 3D satellite under assembly. This program segment should air
in two to three months on the SCI-FI channel.
[Info via David Jordon, AA4KN]
* RS-15 NEWS *
==============
RS-15 telemetry study indicates that the intermittent on-off transponder
and beacon switching is due to insufficient battery holding capacity when
the solar cells are in eclipse conditions.
While Channels 3 and 4, the IFA power supplies remain at 9v and the
Channel 5 stabiliser voltage maintains 5v, other parameters fall.
Channel 1, the RS-15 onboard power supply normally reads around 16 - 17v
in sunlight. When the satellite was in darkness on 10th February at 2236
it had dropped to 14.4v. By 2237:30 it was 14v, by 2239 13.2 v and by
2240:30 only 12.4v. At 2241:00 both transponder and TLM became
intermittent preventing further readings until 2255:30 UTC when it rose
to 15.5v and both beacon and transponder became full time operational
again.
Channel 6, the solar battery voltage, normally some 18.4v, was 17.6v at
2236, 13.2v at 2237:30, and down to 12v by 2239. It came up to 18v at
2255:30 and 18.4v from 2257 UTC.
Channel 7, the solar cell battery current normally some 880mA had dropped
to 400mA at 2236 UTC and then on 0mA from 2237:30 until full operation
started again at 2255:30 UTC by which time it was 880mA.
Users are recommended not to uplink to RS-15 when Channel 1 reads less
than 15v, when Channel 6 is below 17v or when Channel 7 reads no charge.
As the RS-15 path changes and the dusk to dawn line approaches 90 degrees
to the equator as we approach the equinox full time operation should come
about once more. In the meantime, if users will keep their uplinks down
to 100w ERP or less, the battery charge will last longer and possibly
permit continuous nighttime operations.
GM4IHJ's eclipse software shows that RS-15's path is now taking it to an
orbit of increasing sunlight to darkness ratio. By 17th February the
satellite was seeing only 15.3 minutes (12%) of eclipse per orbit which
should return the system to full time operation once more. On 18th
February the eclipse period drops to 11.2 minutes (9%) and then to only
6.4 minutes (5%) on 19th February. From 20th February to 11 March
inclusive it is in full orbit sunlight.
The bad news is that we return to 6.4 minutes of eclipse on 12th March,
increasing to 15.6 minutes on 14th March from when the intermittence will
most likely return. By 5th April we are back to a 36 minute period of
eclipse, this time then decreasing again to just 12.8 minutes again on 7th
May 1995.
On the assumption that the battery is in good condition, we may continue
to expect regular and similar eclipse events in the future.
[Info via G3IOR]
* STATE VECTOR INFO *
=====================
NASA OIG RAID RBBS at Goddard Space Flight Center (GSFC) is now posting
state vectors for the Space Shuttle around the clock, 7 days a week when
the Shuttle is on-orbit. The vectors are posted every hour and are
typically 1-2 hours old. This is therefore (generally) the most current
orbital information available to the general public for the Space Shuttle.
NASA OIG RAID RBBS may be accessed via the Internet or at (301) 262-6784.
A new (freeware) program called VEC2VIF was written by Curtis Haase that
extracts the most current state vector from the file posted on NASA OIG
RAID RBBS and formats it for direct read by VEC2TLE, which converts the
vector data to NASA 2-line style Keplerian elements. Curtis includes a
batch file that calls the command-line/batch version of VEC2TLE (i.e.,
V2KEP) that makes the whole operation pretty much "plug and play."
The most current versions of VEC2TLE and VEC2VIF are available from
CompuServe, and Ham-It-Up BBS (516) 878-4906 or (516) 878-3638. VEC2TLE
is available from AMSAT-NA and NASA Spacelink BBS as well. Future
releases of VEC2TLE will have VEC2VIF bundled in the distribution files.
[Info via Ken Ernandes]
* APT SATELLITE NEWS *
======================
The following was observed 50.61 deg NLat, 7.55 deg ELon; FEB 12, 1995:
Following the satellite-name is the approximate hour (local=sun-time) and
motion-direction of the pass (N=northbound, S=southbound).
NOAA-9 11:S APT 137.62 MHz On
NOAA-10 17:N APT 137.50 MHz On
NOAA-12 19:N APT 137.50 MHz On
NOAA-14 13:N APT 137.62 MHz On
Meteor 3-5 12:N APT 137.85 MHz On
Not active: Meteor 2-21 and OKEAN 1-7. Leo Wikholm from Finland has
reported that he was able to copy APT of OKEAN 1-7 from passes over
northern Russia from time to time.
[Info via Peter Henne @ German Nat.Research Center.f.Comp.Science]
* THANKS! *
===========
Thanks to all those who sent messages of appreciation to SpaceNews,
especially:
F5DGQ KG5OA YV5AMW
* FEEDBACK/INPUT WELCOMED *
===========================
Mail to SpaceNews should be directed to the editor (John, KD2BD) via any
of the following paths:
FAX : 1-908-747-7107
PACKET : KD2BD @ KS4HR.NJ.USA.NA
INTERNET : kd2bd@amsat.org -or- magliaco@pilot.njin.net
SATELLITE : AMSAT-OSCAR-16, LUSAT-OSCAR-19
MAIL : John A. Magliacane, KD2BD
Department of Engineering and Technology
Advanced Technology Center
Brookdale Community College
Lincroft, New Jersey 07738
U.S.A.
<<=- SpaceNews: The first amateur newsletter read in space! -=>>
/EX