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CX2SA > SATDIG 29.12.09 17:58l 902 Lines 30337 Bytes #999 (0) @ WW
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Sent: 091229/1552Z @:CX2SA.LAV.URY.SA #:28824 [Minas] FBB7.00e $:AMSATBB4688
From: CX2SA@CX2SA.LAV.URY.SA
To : SATDIG@WW
Today's Topics:
1. Re: HELP WITH YAESU FT 847 CAT CONTROL SETUP (Erich Eichmann)
2. Re: AO-51 mode change and recommendation (Mateusz)
3. Back on the birds after 15-year absence (Bato, Andras)
4. Re: Back on the birds after 15-year absence (Peter)
5. Re: Back on the birds after 15-year absence (Mike Rupprecht)
6. Re: Back on the birds after 15-year absence (Andrew Glasbrenner)
7. AO-51 end of the aftenoon pass (Mateusz)
8. Re: AO-51 mode change and recommendation (jp-byj-free)
9. Re: AO-51 mode change and recommendation (OZ1MY)
10. Re: Back on the birds after 15-year absence (Robert Bruninga)
11. Re: back on the birds after 15-year absence - want tips on
antenna system (Roger Kolakowski)
12. Re: AO-51 mode change and recommendation (Luc Leblanc)
13. AO-51 USB/FM mode (Matt)
14. HD TV Noise (H. Vordenbaum)
15. Re: Question about vacuum and power module for
lineartransponder (Robert Bruninga)
16. GO-32 over North America? (Mark L. Hammond)
17. Re: AO-51 mode change and recommendation (Idle-Tyme)
18. Re: GO-32 over North America? (Mike Rupprecht)
----------------------------------------------------------------------
Message: 1
Date: Tue, 29 Dec 2009 12:49:01 +0100
From: "Erich Eichmann" <erich.eichmann@xxxxxxxx.xx>
Subject: [amsat-bb] Re: HELP WITH YAESU FT 847 CAT CONTROL SETUP
To: "David Wing" <david@xxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <FA4D3E4BAAE34476AB9B2AE97600BD3E@xxxxxxxxxxxxxx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
David,
to set the CAT baud rate open menu "Radio Setup" and in the upper left
section click on the control of the upper combo box (right hand of the word
"Model"). In the list that opens select "Baudrate". Click on the control of
the combo box below and select 57600.
There is a detailed description in the "Hints(Radio) for .....Yaesu users".
The file can be opened from the SatPC32 menu "?".
73s, Erich, DK1TB
----- Original Message -----
From: "David Wing" <david@xxxxxx.xxx>
To: "'Albert Onley'" <k4vhv@xxxx.xxx>; "'Amsat -bb'" <amsat-bb@xxxxx.xxx>
Sent: Tuesday, December 29, 2009 4:48 AM
Subject: [amsat-bb] Re: HELP WITH YAESU FT 847 CAT CONTROL SETUP
> Al, I find that I need to toggle from C+ to C- and back to C+ in order to
> get things to work on my FT-847. I usually select the satellite, turn on
> the rotator, turn on the radio and then toggle the CAT control...see if
> this
> helps.
>
> FYI, I also have my CAT rate at 57600...can't seem to find that setting in
> SatPC32 anywhere though. I'm using an ACER Netbook running XP, com4 for
> radio, com6 for rotator and using RT Systems serial to USB
> converters...and
> a real null modem cable on the CAT (not all cables are null modem).
>
> 73
> David
> K6CDW
>
>
> -----Original Message-----
> From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
> Behalf Of Albert Onley
> Sent: Monday, December 28, 2009 4:48 PM
> To: Amsat -bb
> Subject: [amsat-bb] HELP WITH YAESU FT 847 CAT CONTROL SETUP
>
> I am trying to get my ft 847 to work in CAD mode . I have the C+ on,
> using NULL MODEM
> CABLE ,baud set to 57600 BOTH IN RADIO AND PROGRAM , using COM 1.
> RUNNING
> XP HOME WITH SP 2. AL K4VHV
> _______________________________________________
> 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: 2
Date: Tue, 29 Dec 2009 13:08:06 +0100
From: "Mateusz" <sq7dqx@xxxxxx.xxxx.xx>
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
To: <amsat-bb@xxxxx.xxx>
Message-ID: <4DF694DEF8E44687B877C5ED680A3C1D@xx>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
> Attempted to use this mode on 2 passes but was not successful.
> Several stations tried to work on the first pass over Australia
> (07:51 UTC 29 Dec) but audio was very weak and there was a lot of
> interference on the signal.
> Some stations had difficulty netting onto frequency, probably because
> they could not hear themselves clearly.
> On the second pass I could hear no other stations attempting to access
> and while the downlink signal was strong there were all manner of
> noises present and only once or twice could I actually hear my voice
> among the noises.
> I'm sure that last time AO-51 was in this mode it worked reasonably
> well.
> Will be interested to hear reports from other continents to see if the
> interference was specific to this region.
>
> 73
> Alex / VK5ALX
Hallo
I tried at today morning and at the noon.
At the morning i heard SQ1 station but I did not finish qso.
At the noon I was copied by UA9UIZ and OZ1MY but I am not sure raport from
Ib (57 I can hear on record) and locator given by UA9UIZ is not NO46 but
NV46 (distortion?).
Signal is realy week from USB/FM transponder probably due to latest magnetic
torque experiment and changed antenna orientation on norhern hemisphere. It
sounds like fraction of one watt, not like almost 2W transmitter.
Here is a record (cut, too much noise):
http://www.enduro.idl.pl/audio_sat/ao51_ssb_fm.mp3 and sorry for too low
quality of sound.
Signal is low (I know, 53 is a little too optimistic) but I did it :)
Matt SQ7DQX
------------------------------
Message: 3
Date: Tue, 29 Dec 2009 12:14:46 +0000
From: "Bato, Andras" <bato@xxxxxxx.xx>
Subject: [amsat-bb] Back on the birds after 15-year absence
To: amsat-bb@xxxxx.xxx
Message-ID: <4B39F2B6.1000805@xxxxxxx.xx>
Content-Type: text/plain; charset=ISO-8859-2; format=flowed
Hello all,
Seems this list is moderated and does not allow any kind of criticism!
I shoulds say, I am a regular on usable satellites but I can not
understand how a strong organization like AMSAT is not able to keep its
webpage fresh?!
UWE-2 has died long ago but is is still in the the list, etc.
Many of us know this but those who come back after years really not know
when and which sat to use or listen to!
gl de ha6nn
Andras
------------------------------
Message: 4
Date: Tue, 29 Dec 2009 07:29:53 -0500
From: Peter <roi@xxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Back on the birds after 15-year absence
To: AMSAT-BB@xxxxx.xxx
Message-ID: <001b01ca8882$bd7703a0$6901a8c0@xxxxx>
Content-Type: text/plain; charset=Windows-1252
Andras,
I have not listened for UWE-2, however their web site indicates that the
beacon is working in "housekeeping mode", if that is correct the AMSAT site
is accurate, Happy Holidays,
73,
Pete, WB2OQQ
------------------------------
Message: 5
Date: Tue, 29 Dec 2009 13:46:48 +0100
From: "Mike Rupprecht" <mail@xxxxxxxxxxxxxx.xx>
Subject: [amsat-bb] Re: Back on the birds after 15-year absence
To: "'Peter'" <roi@xxxxxxxxx.xxx>, <AMSAT-BB@xxxxx.xxx>
Message-ID: <004501ca8884$fca39500$f5eabf00$@xx>
Content-Type: text/plain; charset="iso-8859-1"
Pete,
I could not hear any signals from UWE-2 over Europe since end of September.
The last packet I heard was from Sep 25th. ->
http://www.dk3wn.info/p/?p=8447
There is no activity from the ground station on 2m/70cm.
73, Mike
DK3WN
-----Urspr?ngliche Nachricht-----
Von: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx Im
Auftrag von Peter
Gesendet: Dienstag, 29. Dezember 2009 13:30
An: AMSAT-BB@xxxxx.xxx
Betreff: [amsat-bb] Re: Back on the birds after 15-year absence
Andras,
I have not listened for UWE-2, however their web site indicates that the
beacon is working in "housekeeping mode", if that is correct the AMSAT site
is accurate, Happy Holidays,
73,
Pete, WB2OQQ
_______________________________________________
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: 6
Date: Tue, 29 Dec 2009 08:28:30 -0500
From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
Subject: [amsat-bb] Re: Back on the birds after 15-year absence
To: "Bato, Andras" <bato@xxxxxxx.xx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4B3A03FE.2060509@xxxxxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> I shoulds say, I am a regular on usable satellites but I can not
> understand how a strong organization like AMSAT is not able to keep its
> webpage fresh?!
>
> UWE-2 has died long ago but is is still in the the list, etc.
>
> Many of us know this but those who come back after years really not know
> when and which sat to use or listen to!
>
> gl de ha6nn
> Andras
>
>
So how about using the little link at the bottom of the page and letting
us know that it is off the air? Wouldn't that be the more productive
thing to do than complain about it to the whole world? There is one
person that maintains the status indicators on that page, and I'm sure
he would not mind the help.
73, Drew KO4MA
------------------------------
Message: 7
Date: Tue, 29 Dec 2009 14:42:43 +0100
From: "Mateusz" <sq7dqx@xxxxxx.xxxx.xx>
Subject: [amsat-bb] AO-51 end of the aftenoon pass
To: <amsat-bb@xxxxx.xxx>
Message-ID: <1B32B82D719345A58CCF6683755FDBDF@xx>
Content-Type: text/plain; format=flowed; charset="iso-8859-2";
reply-type=original
Here is a record from last seconds of aftenoon pass of AO-51 over Russia and
East Europe, there was something unusual:
http://www.enduro.idl.pl/audio_sat/ao51ssb_fm_end.mp3
I swithed receiver to USB and tuned to that signal (Doppler correction ON),
it was not local, it was dissapear as AO-51 went under horizon.
Matt SQ7DQX
------------------------------
Message: 8
Date: Tue, 29 Dec 2009 14:51:54 +0100
From: jp-byj-free <jp.f6byj@xxxx.xx>
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Message-ID: <4B3A097A.1080308@xxxx.xx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi All.
Here, listens 2 Europe pass (08h00 and 09h40)
and only 1 qso to every pass
I think that a lot of OM Uplink in FM !
Of more a lot of QRM on the entry VHF when the SAT is at the SOUTH
I have tested also the CW for the 1st January... that seems good.
Best 73 Jep F6BYJ
vk5alx@xxxxx.xxx a ?crit :
> Attempted to use this mode on 2 passes but was not successful.
> Several stations tried to work on the first pass over Australia
> (07:51 UTC 29 Dec) but audio was very weak and there was a lot of
> interference on the signal.
> Some stations had difficulty netting onto frequency, probably because
> they could not hear themselves clearly.
> On the second pass I could hear no other stations attempting to access
> and while the downlink signal was strong there were all manner of
> noises present and only once or twice could I actually hear my voice
> among the noises.
> I'm sure that last time AO-51 was in this mode it worked reasonably
> well.
> Will be interested to hear reports from other continents to see if the
> interference was specific to this region.
>
> 73
> Alex / VK5ALX
>
>
>
>
> _______________________________________________
> 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: 9
Date: Tue, 29 Dec 2009 14:54:32 +0100
From: "OZ1MY" <oz1my@xxxxxx.xx>
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
To: "Mateusz" <sq7dqx@xxxxxx.xxxx.xx>, <amsat-bb@xxxxx.xxx>,
<ao51-modes@xxxxx.xxx>
Message-ID: <001501ca888e$72e7ae00$6401a8c0@xxxxxx.xx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Alex and Mateusz,
As you write it behaves strange ?
At the pass with AOS here in Copenhagen at 1318 UTC
it seems like some stations are using very HIGH power and
that may be the problem.I could hear Mateusz and UA9UIZ
- but as you said the audio was very low.
Another thing I experienced was a complete cut of of the
downlink ??
I thought it was local QRM at first - but may be it was the
satellite.
Did you hear the same ??
Last time it was in this mode it worked OK.
73 OZ1MY
Ib
----- Original Message -----
From: "Mateusz" <sq7dqx@xxxxxx.xxxx.xx>
To: <amsat-bb@xxxxx.xxx>
Sent: Tuesday, December 29, 2009 1:08 PM
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
> > Attempted to use this mode on 2 passes but was not successful.
> > Several stations tried to work on the first pass over Australia
> > (07:51 UTC 29 Dec) but audio was very weak and there was a lot of
> > interference on the signal.
> > Some stations had difficulty netting onto frequency, probably because
> > they could not hear themselves clearly.
> > On the second pass I could hear no other stations attempting to access
> > and while the downlink signal was strong there were all manner of
> > noises present and only once or twice could I actually hear my voice
> > among the noises.
> > I'm sure that last time AO-51 was in this mode it worked reasonably
> > well.
> > Will be interested to hear reports from other continents to see if the
> > interference was specific to this region.
> >
> > 73
> > Alex / VK5ALX
>
>
> Hallo
>
> I tried at today morning and at the noon.
> At the morning i heard SQ1 station but I did not finish qso.
> At the noon I was copied by UA9UIZ and OZ1MY but I am not sure raport from
> Ib (57 I can hear on record) and locator given by UA9UIZ is not NO46 but
> NV46 (distortion?).
> Signal is realy week from USB/FM transponder probably due to latest
magnetic
> torque experiment and changed antenna orientation on norhern hemisphere.
It
> sounds like fraction of one watt, not like almost 2W transmitter.
>
> Here is a record (cut, too much noise):
>
> http://www.enduro.idl.pl/audio_sat/ao51_ssb_fm.mp3 and sorry for too low
> quality of sound.
>
> Signal is low (I know, 53 is a little too optimistic) but I did it :)
>
> Matt SQ7DQX
>
> _______________________________________________
> 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: 10
Date: Tue, 29 Dec 2009 09:50:06 -0500
From: "Robert Bruninga" <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: Back on the birds after 15-year absence
To: <amsat-bb@xxxxx.xxx>
Message-ID: <56C784A6B113423597FA512827F5E4C2@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset="US-ASCII"
> Seems this list is moderated and does not allow any kind of
criticism!
As in any volunteer organization, criticism accomplishes
practically nothing towards forward progress.
Anytime you feel compelled to "criticize" consider replacing
that effort with "contribution".
Contribution and moving forward is what makes volunteer
organizations work, criticism, and kibitzing and grumbling is
what retards them.
Bob, WB4aPR
------------------------------
Message: 11
Date: Tue, 29 Dec 2009 09:49:59 -0500
From: "Roger Kolakowski" <rogerkola@xxx.xxx>
Subject: [amsat-bb] Re: back on the birds after 15-year absence - want
tips on antenna system
To: <amsat-bb@xxxxx.xxx>
Message-ID: <009e01ca8896$3279de80$0300a8c0@xxxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Nice, informative response Drew...I'm keeping this one on the wall!
Roger
WA1KAT
----- Original Message -----
From: "Andrew Glasbrenner" <glasbrenner@xxxxxxxxxx.xxx>
To: "William Hein" <bill.aa4xt@xxxxx.xxx>
Cc: <amsat-bb@xxxxx.xxx>
Sent: Monday, December 28, 2009 9:27 PM
Subject: [amsat-bb] Re: back on the birds after 15-year absence - want
tipson antenna system
> Welcome back! I'll try to answer what I can.
> > Questions:
> >
> > (1) RHCP for the V and U Yagis? Any reason to have switchable
polarity?
> >
> Some LEOs have different circularities for different transmitters. For
> example, AO-51 has both LHCP and RHCP on 70cm. The sense can also change
> during a pass depending on spacecraft orientation and squint. Switchable
> polarity is well worth it in my opinion.
> > (3) Will next gen ham satellites have S-Band downlinks?
> >
> Yes, and AO-51 has an S downlink now, usually about 1 week a month. P3E
> and others will have S.
>
> > (4) Will next gen ham satellites have L-Band uplinks and/or downlinks?
> >
> Yes, and AO-51 and CO-65 use L now also. Kiwisat and P3E will have L also.
>
> > (6) Are these the satellites currently available for 2-way QSOs? AO-7,
AO-27, AO-51, SO-67 & HO-68. Did I miss any?
> >
> Off the top of my head, add ISS, SO-50, VO-52, FO-29 (due to return
> soon), NO-44 sometimes, CO-65 for a real digital challenge. Lots of
> one-way cubesats that can be fun too.
>
> > (7) Any pattern to when AO-7 is in Mode A and Mode B?
> >
> Right now the satellite is in 24/7 illumination, and the onboard timer
> switches modes every 24 hours or thereabouts. Check
> http://oscar.dcarr.org/ as a quick way to figure out which one is on
> right now. When it returns to eclipses, it generally favors B and only
> works while illuminated.
>
> I hope that helps. Joining AMSAT if you're not already a member is a
> good way to support the program, and there is always something
> interesting in the AMSAT Journal. There are several active ops in your
> immediate area, including a BOD member; they may chime in. See ya on the
> air soon.
>
> 73, Drew KO4MA
> _______________________________________________
> 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: 12
Date: Tue, 29 Dec 2009 05:45:44 -0500
From: Luc Leblanc <lucleblanc6@xxxxxxxxx.xx>
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
To: amsat-bb@xxxxx.xxx
Message-ID: <4B399788.29557.8E6936@xxxxxxxxxxx.xxxxxxxxx.xx>
Content-Type: text/plain; charset=US-ASCII
On 28 Dec 2009 at 19:13, Andrew Glasbrenner wrote:
Date sent: Mon, 28 Dec 2009 19:13:24 -0500
From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
Subject: [amsat-bb] AO-51 mode change and recommendation
To: Amsat-BB <amsat-bb@xxxxx.xxx>
> AO-51 has been switched to the SSB/FM crossmode repeater, 145.880 USB
> up, 435.150 FM down. Power output is 1.93 watts. The downlink modulation
> is set very high, so that even very weak signals will be audible. The
> downside to this is that someone running excessive power will cause the
> downlink to distort.If this happens I'll be forced to adjust the
> modulation level down, or possibly end the mode early. For a "normal"
> station, 5 watts on the uplink to a modest gain antenna is entirely
> sufficient. Please use the minimum power necessary. This mode -requires-
> tuning the SSB uplink precisely for Doppler, and to effectively do that
> you will need full duplex.
>
> Please use this for voice communications only, until Straight Key Night,
> when CW will be the designated mode.
>
> Thanks, and enjoy this unusual mode.
>
> 73, Drew KO4MA
> AMSAT-NA VP Operations
> _______________________________________________
On the first 3.9 deg morning pass i was able to hear F6BYJ and an ON station
my own downlink was quite distorted even with any
signal/modulation level.
On the second pass signal peak at S9 plus 20 but my downlink aidio was
rather weak. Signal from the satellite was breaking up but i was
able to hear my downlink with 5 watts for most of the past but as probably a
commanding station was adjusting the levels the near end of
the pass my audio became extremely weak and seems to never getting back at
the AOS to TCA level.
The first morning low pass audio adjustment produce a very good and clean
signal but on the second one audio appears to be muted at AOS to
TCA and became extremely muted on the second half on the pass to a point
where no communication was possible. It is not a signal problem
but just the audio who seems to be adjusted at the right level.
No distortion has been noted too.
The only one problem i was alone for the whole pass speaking to myself...
"-"
Luc Leblanc VE2DWE
Skype VE2DWE
www.qsl.net/ve2dwe
DSTAR urcall VE2DWE
WAC BASIC CW PHONE SATELLITE
------------------------------
Message: 13
Date: Tue, 29 Dec 2009 13:11:34 +0100
From: "Matt" <mateuszpigon@xxxxxx.xxxx.xx>
Subject: [amsat-bb] AO-51 USB/FM mode
To: <amsat-bb@xxxxx.xxx>
Message-ID: <6FA79DCB307B499D9ED50BB589BAB00D@xx>
Content-Type: text/plain; format=flowed; charset="iso-8859-2";
reply-type=original
I forgot to add that elevation was lower than 0.9 degree.
My antennas are pointed to horizon.
Matt
SQ7DQX
------------------------------
Message: 14
Date: Tue, 29 Dec 2009 08:34:19 -0600
From: "H. Vordenbaum" <tower2@xxx.xx.xxx>
Subject: [amsat-bb] HD TV Noise
To: "AmsatBB" <amsat-bb@xxxxx.xxx>
Message-ID: <3584CBBFFF45478E82030D9087413015@xxxxxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Are there any ideas on which HD TV systems generate the least R.F. noise;
Plasma vs. LCD vs LCD/LED ?
I am interested since I am contemplating getting a fairly large screen HD TV
in the near future and am wondering if it will raise the RF noise floor
significantly around the house. The input would be from Time-Warner cable.
There's already some noise birdies from various computers and internet in my
scanners, etc.
73, Harvey
K5HV
------------------------------
Message: 15
Date: Tue, 29 Dec 2009 10:13:25 -0500
From: "Robert Bruninga" <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: Question about vacuum and power module for
lineartransponder
To: <amsat-bb@xxxxx.xxx>
Message-ID: <1AA5464E87484F579E75AD9F825EC51D@xxxxx.xxxx.xxx>
Content-Type: text/plain; charset="US-ASCII"
>>>> My question is how deep the vacuum has to
>>>> be to be able to do a valid test on (space)
>>>> electronics working under space vacuum conditions ?
It depends. We finally got a space vacuum chamber that can pump
down to .00001 Torr. Beginning at atmospheric 760 Torr. So it
can pump to nearly one-hundred-millionth of atmospheric
pressure.
The roughing pump (typical lab pump) can probably get it down to
.01 which I always thought would be plenty good for space
testing.... A high-cost turbine pump runnning at 27,000 RPM
takes it the rest of the way down. I had always figured that
.01 Torr (one one-hundred thousandth of atmospheric woiuld
surely be good enough for most putposes.. Until this year, when
we did a thermal lab and forgot to turn on the turbine pump.
We were demonstrating the properties of radiative heat transfer
(the only way to get rid of heat from components under a vacuum
after you remove all the convection cooling by air. Turns out,
not until we got that final factor of 1000 by turning on the
turbo pump, did we actually get the resluts we expected.
Remember, I posted that here back in late November or so. That
is, the inability of aluminum to radiate away any heat (it is
only 3% as effective as Black). At that time, the point of my
posting, was that of-course, the aluminum has to be CLEAN! Just
the surface oil from handling completely masked the effect. But
it was during this test that we also found that convection
cooling still existed even at .01 Torr. Though we did not
document it... We simply turned on the turbinge pump.
Notice, we were looking for a 3% value compared to a 90% value
of heat transfer. When even that 90% is completely masked by
convection cooling which is orders of magnitude still higher.
So that is why the closer to pure vaccum the better.
But almost all ectronics that are going to get hot are going to
be colored BLACK or other high emissive coating, and so the
radiative cooling will probably be effective at higher
pressures.
So. The answer is, what are you testing for?
Any component that has entraped air or volatiles inside
shouldn't be flown anyway (electrolytic caps). Anything else
that might have entrapped air would change its characteristics
under a vacuum... But with most modern electronics, I woiuld
guess that it is the cooling effects you are most interested
in... But then anything that should get hot, you are going to
use a conductive heat sink on it, and so again, vacuum wont make
much difference.. Etc..
I don't know the right answer, but those are our experiences...
Good luck.
Bob, Wb4aPR
------------------------------
Message: 16
Date: Tue, 29 Dec 2009 10:31:08 -0500
From: "Mark L. Hammond" <marklhammond@xxxxx.xxx>
Subject: [amsat-bb] GO-32 over North America?
To: amsat-bb@xxxxx.xxx
Message-ID:
<5d8cecfe0912290731q1db8774bt533a6705f35ed394@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
Has anybody heard GO-32 over North America in recent weeks?
I've seen good reports from DK3WN, but haven't heard a packet from
GO-32 the last few times I've tried to listen to it...
--
Mark L. Hammond [N8MH]
------------------------------
Message: 17
Date: Tue, 29 Dec 2009 09:46:37 -0600
From: Idle-Tyme <nss@xxx.xxx>
Subject: [amsat-bb] Re: AO-51 mode change and recommendation
To: Luc Leblanc <lucleblanc6@xxxxxxxxx.xx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <4B3A245D.1090708@xxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Just curious, Why voice only?
Why no CW?
Joe WB9SBD
*The Original Rolling Ball Clock
Idle-Tyme.com <http://www.idle-tyme.com>*
Luc Leblanc wrote:
> On 28 Dec 2009 at 19:13, Andrew Glasbrenner wrote:
>
> Date sent: Mon, 28 Dec 2009 19:13:24 -0500
> From: Andrew Glasbrenner <glasbrenner@xxxxxxxxxx.xxx>
> Subject: [amsat-bb] AO-51 mode change and recommendation
> To: Amsat-BB <amsat-bb@xxxxx.xxx>
>
>
>> AO-51 has been switched to the SSB/FM crossmode repeater, 145.880 USB
>> up, 435.150 FM down. Power output is 1.93 watts. The downlink modulation
>> is set very high, so that even very weak signals will be audible. The
>> downside to this is that someone running excessive power will cause the
>> downlink to distort.If this happens I'll be forced to adjust the
>> modulation level down, or possibly end the mode early. For a "normal"
>> station, 5 watts on the uplink to a modest gain antenna is entirely
>> sufficient. Please use the minimum power necessary. This mode -requires-
>> tuning the SSB uplink precisely for Doppler, and to effectively do that
>> you will need full duplex.
>>
>> Please use this for voice communications only, until Straight Key Night,
>> when CW will be the designated mode.
>>
>> Thanks, and enjoy this unusual mode.
>>
>> 73, Drew KO4MA
>> AMSAT-NA VP Operations
>> _______________________________________________
>>
>
> On the first 3.9 deg morning pass i was able to hear F6BYJ and an ON
station my own downlink was quite distorted even with any
> signal/modulation level.
>
> On the second pass signal peak at S9 plus 20 but my downlink aidio was
rather weak. Signal from the satellite was breaking up but i was
> able to hear my downlink with 5 watts for most of the past but as probably
a commanding station was adjusting the levels the near end of
> the pass my audio became extremely weak and seems to never getting back at
the AOS to TCA level.
>
> The first morning low pass audio adjustment produce a very good and clean
signal but on the second one audio appears to be muted at AOS to
> TCA and became extremely muted on the second half on the pass to a point
where no communication was possible. It is not a signal problem
> but just the audio who seems to be adjusted at the right level.
>
> No distortion has been noted too.
>
> The only one problem i was alone for the whole pass speaking to myself...
>
> "-"
>
>
> Luc Leblanc VE2DWE
> Skype VE2DWE
> www.qsl.net/ve2dwe
> DSTAR urcall VE2DWE
> WAC BASIC CW PHONE SATELLITE
>
>
> _______________________________________________
> 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
>
> ------------------------------------------------------------------------
>
>
> No virus found in this incoming message.
> Checked by AVG - www.avg.com
> Version: 9.0.724 / Virus Database: 270.14.123/2592 - Release Date:
12/29/09 01:47:00
>
>
------------------------------
Message: 18
Date: Tue, 29 Dec 2009 16:49:32 +0100
From: "Mike Rupprecht" <mail@xxxxxxxxxxxxxx.xx>
Subject: [amsat-bb] Re: GO-32 over North America?
To: "'Mark L. Hammond'" <marklhammond@xxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <005001ca889e$84283bc0$8c78b340$@xx>
Content-Type: text/plain; charset="iso-8859-1"
Hi Mark,
please check both downlink frequencies - they change often:
435.225 MHz OR 435.325 MHz
73, Mike
DK3WN
-----Urspr?ngliche Nachricht-----
Von: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx Im
Auftrag von Mark L. Hammond
Gesendet: Dienstag, 29. Dezember 2009 16:31
An: amsat-bb@xxxxx.xxx
Betreff: [amsat-bb] GO-32 over North America?
Has anybody heard GO-32 over North America in recent weeks?
I've seen good reports from DK3WN, but haven't heard a packet from
GO-32 the last few times I've tried to listen to it...
--
Mark L. Hammond [N8MH]
_______________________________________________
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 member? Join now to support the amateur satellite program!
http://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 4, Issue 688
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