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CX2SA > SATDIG 12.04.09 20:10l 909 Lines 29446 Bytes #999 (0) @ WW
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Today's Topics:
1. predict -s starts then immediately crashes (Eric Fort)
2. Re: predict -s starts then immediately crashes (Joe Veldhuis)
3. Re: predict -s starts then immediately crashes (Iain Young, G7III)
4. Rotator Yaesu G-5400B (Vincenzo Mone)
5. Frequency advice requested (Graham Shirville)
6. Re: predict -s starts then immediately crashes (Eric Fort)
7. Preamps?? (Jerry Felts)
8. Re: NO-44 and ISS (Bob Bruninga )
9. Pre Amps (Cotejaune2@xxx.xxxx
10. Re: Frequency advice requested (Steve Meuse)
11. FT-736R SERVICE MANUAL (books47925@xxxxxxx.xxxx
12. Re: FT-736R SERVICE MANUAL (Nigel Gunn G8IFF/W8IFF)
13. Re: Preamps?? (James Duffey)
14. Re: Preamps?? (Gary "Joe" Mayfield)
15. Fargo Hamfest (Gary "Joe" Mayfield)
16. Re: Frequency advice requested (Stan W1LE)
17. rss feed (Joseph Armbruster)
----------------------------------------------------------------------
Message: 1
Date: Sun, 12 Apr 2009 03:01:52 -0700
From: Eric Fort <eric.fort@xxxxx.xxx>
Subject: [amsat-bb] predict -s starts then immediately crashes
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Message-ID:
<2ad2af430904120301r40bdca28v4de1b92fd12a7e3b@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
predict -s (pedict invoked as a server) immediately crashes (terminates)
after startup. anyone have an idea why it would do this? (works fine when
not invoked as a server)
Thanks,
Eric
AF6EP
------------------------------
Message: 2
Date: Sun, 12 Apr 2009 06:16:59 -0400
From: Joe Veldhuis <jvn8fq@xxxxx.xxx>
Subject: [amsat-bb] Re: predict -s starts then immediately crashes
To: amsat-bb@xxxxx.xxx
Message-ID: <20090412061659.abba367d.jvn8fq@xxxxx.xxx>
Content-Type: text/plain; charset=US-ASCII
Does GDB give any useful information?
-Joe, N8FQ
On Sun, 12 Apr 2009 03:01:52 -0700
Eric Fort <eric.fort@xxxxx.xxx> wrote:
> predict -s (pedict invoked as a server) immediately crashes (terminates)
> after startup. anyone have an idea why it would do this? (works fine when
> not invoked as a server)
>
> Thanks,
>
> Eric
> AF6EP
------------------------------
Message: 3
Date: Sun, 12 Apr 2009 11:25:54 +0100
From: "Iain Young, G7III" <g7iii@xxxxx.xxx>
Subject: [amsat-bb] Re: predict -s starts then immediately crashes
To: amsat-bb@xxxxx.xxx
Message-ID: <49E1C1B2.7090707@xxxxx.xxx>
Content-Type: text/plain; charset=windows-1250; format=flowed
> On Sun, 12 Apr 2009 03:01:52 -0700
> Eric Fort <eric.fort@xxxxx.xxx> wrote:
>
>> predict -s (pedict invoked as a server) immediately crashes (terminates)
>> after startup. anyone have an idea why it would do this? (works fine when
>> not invoked as a server)
Do you have predict listed as a service in /etc/services ? Should be a
line like this:
predict 1210/udp # predict -- satellite tracking
Is something else using UDP Port 1210 ? That might cause it.Check with
netstat -an | grep 1210
73s
Iain
------------------------------
Message: 4
Date: Sun, 12 Apr 2009 13:02:10 +0200
From: "Vincenzo Mone" <vimone@xxxxx.xx>
Subject: [amsat-bb] Rotator Yaesu G-5400B
To: "Amsat - BBs" <amsat-bb@xxxxx.xxx>
Message-ID:
<!&!AAAAAAAAAAAYAAAAAAAAALgqrd2N1rRAiaQvRd7pgRDCgAAAEAAAADYfylNYPIdCjvPg
GWOwWfkBAAAAAA==@xxxxx.xx>
Content-Type: text/plain; charset="US-ASCII"
Hi Folks,
sorry for the OT message.
I own the rotator Yaesu G-5400B which are a Azimuth and elevation rotators.
I had enclosed with the pack when I bought it an "L" bracket.
Unfortunately due to maintenance I have lost the Bracket.
Please is there anybody which own one and can pass me all the measures So I
can build a new one? I need the measures of the "L" bracket and the right
Positions of the holes to fix the two rotators.
Any help will be really appreciated.
Thanks in advance
I want to thanks to Jim K6CCC and Stan W1Le for their replies but the
problem is that They have the "U" bracket while I need the measurements for
the "L" Bracket.
The rotator was bought in the far 1990 and it was received with the "L"
bracket and The Elevation rotator has just 4 holes on one side while the new
one has 2 holes on On the bottom of the two sides.
73 de Enzo IK8OZV
EasyLog 5 BetaTester
EasyLog PDA BetaTester
WinBollet BetaTester
D.C.I. CheckPoint Regione Campania
Skype: ik8ozv8520
***************************************
***** GSM +39 338 9749786 *****
***** SMS +39 338 9749786 *****
***** FAX +39 328 7244294 *****
*** 2nd e-mail: vimone@xxx.xx ***
***************************************
------------------------------
Message: 5
Date: Sun, 12 Apr 2009 12:54:35 +0100
From: "Graham Shirville" <g.shirville@xxxxxxxxxx.xxx>
Subject: [amsat-bb] Frequency advice requested
To: <amsat-bb@xxxxx.xxx>
Message-ID: <2DA26D92F3FB47EC8B983E324197D707@xxxxxxx.xxxxx>
Content-Type: text/plain; charset="iso-8859-1"
Hi all,
AMSAT-UK is involved with the development of a "C Band" beacon to be deployed
on a satellite in low earth orbit sometime during 2012. The satellite is ESEO
- The European Student Earth Orbiter and the beacon will be part of an amateur
package which will also include U/S and U/V linear transponders.
The beacon has to be somewhere in the 5830-5850MHz part of the band as this is
the allocation that is available for space to earth transmissions. So the
question is - what would be the best part of the band to use - taking into
account existing ground equipment and antennas (if any) and potential QRM from
other terrestrial systems.
Any ideas or suggestions will be most welcome!
thanks
Graham
G3VZV
------------------------------
Message: 6
Date: Sun, 12 Apr 2009 05:08:12 -0700
From: Eric Fort <eric.fort@xxxxx.xxx>
Subject: [amsat-bb] Re: predict -s starts then immediately crashes
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Message-ID:
<2ad2af430904120508h37b5e4a9x45213c080043625b@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1
under debian predict runs setup like it should then terminates never getting
to the multi satelite screen. on running it again it starts over in setting
up the qth, even though ~/.predict/predict.qth is present.
just fixed the problem:
the following 3 files seem to need to be present for predict to run:
~/.predict/predict.qth
~/.predict/predict.db
_/.predict/predict.tle
to run as a server /etc/ services must have port 1210/udp assigned to
predict.
my osx install also now runs the predict server. osx assigns aborher
service to port 1210 by default.
noww both work.
Eric
AF6EP
On Sun, Apr 12, 2009 at 3:01 AM, Eric Fort <eric.fort@xxxxx.xxx> wrote:
> predict -s (pedict invoked as a server) immediately crashes (terminates)
> after startup. anyone have an idea why it would do this? (works fine when
> not invoked as a server)
>
> Thanks,
>
> Eric
> AF6EP
>
>
>
------------------------------
Message: 7
Date: Sun, 12 Apr 2009 06:22:40 -0600
From: Jerry Felts <nr5ajerry@xxxxx.xxx>
Subject: [amsat-bb] Preamps??
To: amsat-bb@xxxxx.xxx
Message-ID:
<21baf9ff0904120522q71e2819dod1e30f4a1fcf97bc@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
I've seen Preamps mentioned several times now so Who? What? Where? I have
not seen them in the AES catalog I got the other day. Can you build one?
Need info on them!!
Jerry - NR5A
--
Jerry - NR5A - South Dakota
www.freewebs.com/nr5a
http://groups.yahoo.com/group/Minimalist_QRP_Transceivers/
http://www.cakewalkblogs.com/nr5asminimalradio/index.aspx
http://nr5abeaconblog.blogspot.com/
------------------------------
Message: 8
Date: Sun, 12 Apr 2009 08:25:53 -0400 (EDT)
From: "Bob Bruninga " <bruninga@xxxx.xxx>
Subject: [amsat-bb] Re: NO-44 and ISS
To: Mike Rupprecht <mail@xxxxxxxxxxxxxx.xx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <20090412082553.AJL45573@xxx.xxxxxxx.xxxx.xxx>
Content-Type: text/plain; charset=iso-8859-1
> I remember that you asked us NOT to
> digipeat via W3ADO-1. From time to time
> I listen to NO-44 and note that the
> batteries pretty weak. Only some
> packets (from always the same European
> station) come through...
Good question. We ask people to never use automatic unattended beacons via
W3ADO-1.
Especially when we are trying to recover PCSAT (3 times a year in the winter
time), then we need every possible mA of current to try to get command link.
Then we make many postings asking users to not digipeat via W3ADO-1.
But when PCSAT is mostly dead, the command station does not try to recover, so
human attended users may use it if they want. But everyone must remember
that PCSAT is a PACKET digipeaterr and it needs TEN times the current during
TX than it does for the receiver and CPU. This is why you can hear PCSAT
attempt to TX a packet, but it cannot even maintain that current for even 1
second, so the packets die before the end of the second and it cannot be
decoded.
AND that packet attempt has consumed TEN times the current it needs to
operate. So the only successful packets will be AFTER a long period of
silence. That is why we ask that ONLY human operators MANUALLY transmit a
packet ONLY when they think they have a chance at a digipeat. It is a game of
skill with one bullet. Not a game of shotguns...
EACH attempt at a packet kills the spacecraft for 10 times longer and prevents
others from using it. So we do not want any unattended periodic beacons from
users that KILL the satellite when they are not even there to listen.
The problem is, that there is only enough solar energy on a good noon-time
pass for maybe 2 or 3 packets TOTAL during the pass. And that is only if they
get lucky and transmit after a long period of silence when no one else
attempts it.
Of course, asking everyone to share (not transmit) so that one person can get
lucky (and transmit) is a hard problem in human nature. And especially over
densly populated areas like Europe. See the "tragedy of the commons".
http://en.wikipedia.org/wiki/Tragedy_of_the_commons
So, yes it is ok. But no one will be successful if everyone tries.
Hope that helps.
Bob, Wb4APR
>-----Urspr?ngliche Nachricht-----
>Auftrag von Bob Bruninga
>
> It is easy to see. Each of these two satellites
> have an automated APRS web page where you
> can literally *see* the activity up to date.
> You can see the last packet heard by anyone,
> and you can see who heard it. And you can see
> whree they are.
>
> For ISS, see www.ariss.net
> For NO-44 see http://pcsat.aprs.org
>
> Each packet heard is shown, sorted by how
> long ago it was heard. If you click on
> the station, you can see what sat-gate heard
> it an injected it into the system. The SATgate
> is the callsign immediately after the QAO or
> QAR or QAS construct. You can then see where
> they are by entering their call into the
> http://map.findu.com/CALL
>
>Looking at the ARISS page right now at 9:27 PM Mountain time, you can see
>that about 8 stations have been heard today (about 5 or 6 hours ago) and
>that those are the only ones that have been heard then since 9 days ago. So
>it looks like you might be lucky. This tells us that the crew on ISS did
>turn on packet mode about 6 hours ago, and 10 people got through. ANd this
>is the first time it has been on in 9 days.
>
>Now, click on KN6NS-1 for example, and you can see in his packet:
>
>KN6NS-1>S3PQSX,RS0ISS-4*,WIDE3-3,qAS,KD8CAO-6:'-_-l -/]ok
>
>That he was digipeated by RS0ISS-4* (the ISS callsign) and his packet was
>heard by KD8CAO-6 and injected into the APRS internet where this web page
>then saw it and put it on this web page. The ISS signal is strong. It is
>black and white. If it is ON, then you will hear it on ANY base station
>antenna. When it is off, no one will hear it.
>
>Now, it has been 5 hours since the last station heard, but this does not
>mean it is back off. Just look at the orbit. Where is ISS now and where
>has it been for the last 5 hours. Maybe it has not been over any active ham
>country. So it -could- still be on.
>
>BUT on the other hand. If you can -see- on your tracking program that the
>ISS has passed over the USA or Europe in the last few hours, and you do
>-not- see any packets on the web page, then it is safe to conclude that the
>system is presently off.
>
>Similarly, you can look at http://pcsat.aprs.org
>
>and see that about 8 statiosn were heard today,
>7 a day ago and so on, on down. But PCSAT (NO44) is not black and white:
>
>1) it is totally dead in the dark
>2) it is barely alive in the light
>3) it is ONLY strong enough to complete a 1 second user packet relay
>usually when it passes right under the sun.
>4) and only in the northern hemisphere where the best solar panels face
>"up".
>5) and it is 10 times weaker than ISS so you will only hear it if it is high
>in the sky at your location.
>6) therefore the only successful stations are usually under the satellite
>about mid-day. And there is a two month or so cycle as to where that is
>occuring on any given day...
>7) and these will not get to the web page, unless there is also a satgate in
>the footprint to relay it to the APRS internet and hence to that web page.
>
>SO, those two web pages give you the global bird's eye view live as to what
>is happening with those birds. sleuthing out this info can give you a good
>feel what is going on.
>
>Good luck.
>'At least now you know the ISS does work. Or at least it did 5 hours ago
>today...
>
>Bob, Wb4APR
------------------------------
Message: 9
Date: Sun, 12 Apr 2009 10:01:03 EDT
From: Cotejaune2@xxx.xxx
Subject: [amsat-bb] Pre Amps
To: amsat-bb@xxxxx.xxx
Message-ID: <d1a.3ec77303.37134e1f@xxx.xxx>
Content-Type: text/plain; charset="US-ASCII"
Jerry check out _www.advancedreceiver.com_
(http://www.advancedreceiver.com) Great pre amps and great people to deal
with.
**************Feeling the pinch at the grocery store? Make dinner for $10
or less. (http://food.aol.com/frugal-feasts?ncid=emlcntusfood00000001)
------------------------------
Message: 10
Date: Sun, 12 Apr 2009 10:12:26 -0400
From: Steve Meuse <smeuse@xxxx.xxx>
Subject: [amsat-bb] Re: Frequency advice requested
To: Graham Shirville <g.shirville@xxxxxxxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <20090412141226.GC11541@xxxx.xxx>
Content-Type: text/plain; charset=us-ascii
Graham Shirville expunged (g.shirville@xxxxxxxxxx.xxxxx
> Any ideas or suggestions will be most welcome!
Not taking into account other users of that band, my initial reaction was "A
convenient multiple of the LO you are selecting".
But that's obvious....
-Steve
N1JFU
------------------------------
Message: 11
Date: Sun, 12 Apr 2009 10:13:07 -0400 (EDT)
From: books47925@xxxxxxx.xxx
Subject: [amsat-bb] FT-736R SERVICE MANUAL
To: amsat-bb@xxxxx.xxx
Message-ID:
<30142499.1239545587038.JavaMail.root@xxxxxxxxxxxxxxxx.xxx.xx.xxxxxxxxx.
xxx>
Content-Type: text/plain; charset=UTF-8
Hello All,
Does anyone know of a source for a Yaesu FT-736R
Service Manual? My old rig still works great, but
I would like to try to find a copy of the service
manual. I recently read a post about stabilizing
the frequency of the FT-847, and I thought that
maybe I can make my old FT-736R even better.
Thank You for any information on a source.
73 & Happy Easter!
Steve KB8VAO
------------------------------
Message: 12
Date: Sun, 12 Apr 2009 14:19:50 +0000
From: Nigel Gunn G8IFF/W8IFF <nigel@xxxxx.xxx>
Subject: [amsat-bb] Re: FT-736R SERVICE MANUAL
To: books47925@xxxxxxx.xxx
Cc: amsat-bb@xxxxx.xxx
Message-ID: <49E1F886.8000902@xxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
I've got one if you need to know anything specific.
Got it fom Yaesu UK.
books47925@xxxxxxx.xxx wrote:
> Hello All,
> Does anyone know of a source for a Yaesu FT-736R
> Service Manual? My old rig still works great, but
> I would like to try to find a copy of the service
> manual. I recently read a post about stabilizing
> the frequency of the FT-847, and I thought that
> maybe I can make my old FT-736R even better.
> Thank You for any information on a source.
>
> 73 & Happy Easter!
> Steve KB8VAO
>
> _______________________________________________
> 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
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10:51:00
>
--
Nigel A. Gunn, 1865 El Camino Drive, Xenia, OH 45385-1115, USA. tel +1 937
825 5032
Amateur Radio G8IFF W8IFF (was KC8NHF), e-mail nigel@xxxxx.xxx www
http://www.ngunn.net
Member of ARRL, GQRP #11396, QRPARCI #11644, SOC #548, Flying Pigs QRP Club
International #385,
Dayton ARA #2128, AMSAT-NA LM-1691, AMSAT-UK, MKARS, ALC,
GCARES, XWARN
------------------------------
Message: 13
Date: Sun, 12 Apr 2009 08:24:45 -0600
From: James Duffey <JamesDuffey@xxxxxxx.xxx>
Subject: [amsat-bb] Re: Preamps??
To: Jerry Felts <nr5ajerry@xxxxx.xxx>
Cc: amsat-bb@xxxxx.xxx
Message-ID: <2465497E-48D5-4B8D-989A-4AF9D4DC188D@xxxxxxx.xxx>
Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
Jerry - Preamps at the antenna help. They help a lot if you have a
setup that is limited by receiver performance and/or feedline loss.
They won't help if you are limited by the noise environment. They
usually help a lot for satellite operation as there is usually not
much external noise when the antenna is pointed to empty space rather
than to your neighbor's lamp dimmer.
For two meters a grounded gate preamplifier based on the U310 is a
good choice:
< http://www.ham-radio.com/n6ca/50MHz/50appnotes/U310.html >
Unfortunately, the TO-52 style U310 has gotten pretty expensive; I
think they are $11 a piece from Mouser! Still this is a tried and true
design that is stable and easy to build. You might try the more widely
available and cheaper J310, which is the same part in a plastic package.
MOSFETs also make a good preamp. Here are a couple using the BF981:
< http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=9247 >
< http://www.geocities.com/icdx_australia/bf981preamp.html >
There are lots of other designs out there. The old ARRL handbooks from
the 90s had some nice designs for both dual gate MOSFETs and GaAs
FETs. If you use the same feed line and antenna for transmit, you will
need to add relays to switch around the preamp when you transmit.
Advanced Receiver Research, ARR, is a source of commercial
preamplifiers, and there are some models that have built in RF
switching.
There are other vendors, with higher prices.
A preamp is a good investment to upgrade your station, but it is not a
cure all, particularly if you are dominated by terrestrial noise
source. - DUffey
On Apr 12, 2009, at 6:22 AM, Jerry Felts wrote:
> I've seen Preamps mentioned several times now so Who? What? Where? I
> have
> not seen them in the AES catalog I got the other day. Can you build
> one?
> Need info on them!!
>
> Jerry - NR5A
>
> --
> Jerry - NR5A - South Dakota
> www.freewebs.com/nr5a
> http://groups.yahoo.com/group/Minimalist_QRP_Transceivers/
> http://www.cakewalkblogs.com/nr5asminimalradio/index.aspx
> http://nr5abeaconblog.blogspot.com/
> _______________________________________________
> 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
--
KK6MC
James Duffey
Cedar Crest NM
------------------------------
Message: 14
Date: Sun, 12 Apr 2009 09:34:17 -0500
From: "Gary \"Joe\" Mayfield" <gary_mayfield@xxxxxxx.xxx>
Subject: [amsat-bb] Re: Preamps??
To: "'Jerry Felts'" <nr5ajerry@xxxxx.xxx>, <amsat-bb@xxxxx.xxx>
Message-ID: <COL0-DAV19AC034F9A976954FA48CC8A7E0@xxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Jerry,
Like all things in Ham Radio it boils down to how much you want or have
available to spend :-)
There are lots of folks out there
http://www.advancedreceiver.com
http://www.ssbusa.com/ham.html
http://www.downeastmicrowave.com/
http://www.hamtronics.com/
http://www.ramseyelectronics.com
are just a few.
RSGB and ARRL VHF/UHF handbooks all have designs in them as well.
73,
Joe kk0sd
-----Original Message-----
From: amsat-bb-bounces@xxxxx.xxx [mailto:amsat-bb-bounces@xxxxx.xxxx On
Behalf Of Jerry Felts
Sent: Sunday, April 12, 2009 7:23 AM
To: amsat-bb@xxxxx.xxx
Subject: [amsat-bb] Preamps??
I've seen Preamps mentioned several times now so Who? What? Where? I have
not seen them in the AES catalog I got the other day. Can you build one?
Need info on them!!
Jerry - NR5A
--
Jerry - NR5A - South Dakota
www.freewebs.com/nr5a
http://groups.yahoo.com/group/Minimalist_QRP_Transceivers/
http://www.cakewalkblogs.com/nr5asminimalradio/index.aspx
http://nr5abeaconblog.blogspot.com/
_______________________________________________
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: 15
Date: Sun, 12 Apr 2009 09:54:25 -0500
From: "Gary \"Joe\" Mayfield" <gary_mayfield@xxxxxxx.xxx>
Subject: [amsat-bb] Fargo Hamfest
To: <amsat-bb@xxxxx.xxx>
Message-ID: <COL0-DAV20FB2EA93F6325F06566558A7E0@xxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Thanks for all the help! Due to Mother Nature the Fargo Hamfest has been
postponed until August 1st.
73,
Joe kk0sd
------------------------------
Message: 16
Date: Sun, 12 Apr 2009 11:22:14 -0400
From: Stan W1LE <stanw1le@xxxxxxx.xxx>
Subject: [amsat-bb] Re: Frequency advice requested
To: Graham Shirville <g.shirville@xxxxxxxxxx.xxx>, "'AMSAT BB'"
<AMSAT-BB@xxxxx.xxx>
Message-ID: <49E20726.9070009@xxxxxxx.xxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hello Graham,
Anywhere in the 5830 to 5850 MHz band is a real "odd ball". IMHO
No commercial ham, RX only ,block down converters in that band are
available today.
So:
Pick a RF freq so the Rx LO can be phase locked (with low phase noise),
to an external reference.
If frequency stability is of concern.
Pick a RF and we shall follow. ( Thanks for the leadership.)
Pick a RF, on or about, where others are planning, so my RX
downconverter can be used for multiple sats.
I would probably start with a cost effective gridded dish, linear
polarization.
Though ideal feed may be circularly polarized.
Since the beacon will be fixed in frequency, the RX could use a low beat
(RF - LO = IF) mixer technique
or a high beat (RF + LO = IF) with only a minimum of operator
(headspace) issues.
Select a LO that will not have any spurs in any other ham band.
Select an LO that can be used for multiple microwave bands. Satellite,
terrestrial, EME, whatever....
First look: (nothing magic about 5830 MHz just a starting point)
5830 - 144 = 5686, /5 = 1137.2 MHz
5830 - 145 = 5685, /5 = 1137.00 more opportune freq to phase lock
for stability. ala N5AC LO board
5830 - 70 = 5760 MHz down convert to the 5760 terrestrial ham band,
easier to get a clean LO at 70.0 MHz
5830 + 4538 = 10,368 MHz upconvert to the 10 GHz terrestrial band
5830 + 4621 = 10,451 MHz up convert to the proposed 10 GHz sat down
link, P3E
5830 - 3526 = 2,304 MHz but not an international operating freq
5830 - 4534 = 1296 MHz down convert to the 23 cm band, 4534 /4 = 1133.5 MHz
5830 - 5394 = 436 MHz , 5394 /2, then /3 =899.0
5830 - 430 = 5400 MHz, /6 = 900.0, may be nicer to phase lock with
lower phase noise.
5836 - 436 = 5400
Forget 222 and 903 MHz as an IF, no international appeal.
Nothing yet pops out as ideal.
Why just a beacon (CW ID only) ??, Why not a fixed freq, multichannel
downlink.
Some interest in a CWID beacon, but it is like watching the grass grow.
Lot more interest in down link that folks can participate in or that
changes content, like telemetry, etc.
A U/C or S/C (more complex) transponder would be very interesting and
would spark a lot of interest.
A "bent pipe" FM (single channel like AO-27) U/C transponder may be easiest.
Initial thoughts, Stan, W1LE
Graham Shirville wrote:
>
> Hi all,
>
> AMSAT-UK is involved with the development of a "C Band" beacon to be
deployed on a satellite in low earth orbit sometime during 2012. The satellite
is ESEO - The European Student Earth Orbiter and the beacon will be part of an
amateur package which will also include U/S and U/V linear transponders.
>
> The beacon has to be somewhere in the 5830-5850MHz part of the band as this
is the allocation that is available for space to earth transmissions. So the
question is - what would be the best part of the band to use - taking into
account existing ground equipment and antennas (if any) and potential QRM from
other terrestrial systems.
>
> Any ideas or suggestions will be most welcome!
>
> thanks
>
> Graham
> G3VZV
> _______________________________________________
> Sent via AMSAT-BB@xxxxx.xxx. Opinions expressed are those of the author.
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>
>
------------------------------
Message: 17
Date: Sun, 12 Apr 2009 13:38:55 -0400
From: Joseph Armbruster <josepharmbruster@xxxxx.xxx>
Subject: [amsat-bb] rss feed
To: amsat-bb@xxxxx.xxx
Message-ID: <49E2272F.3030101@xxxxx.xxx>
Content-Type: text/plain; charset="iso-8859-1"
All,
The purpose of this email is to find out if anyone at Amsat would be
interested in a satellite status rss feed.
I am reasonably new to Amsat (and sat stuffs) and thought it would be
useful to have satellite summary and mode data available in an xml
format. I felt RSS combined with some custom amsat tags would be a good
fit. It would essentially be a regular rss feed (xml file) that will be
extended with some amsat specific tags for satellite summary and mode
data. This data could then be used by the community for obtaining
satellite status updates if they'd like. This would definitely be a
nice resource for anyone in the community, especially developers.
To date, i've mentioned the idea to Andrew G and David J and both have
seemed open to have open arms to the idea (Andrew / David, correct me if
i'm wrong :-)) I wanted to open this idea up to others at Amsat.org in
order to get more input.
There are probably quite a few challenges here, including:
A) Determining where all the sat status data originates and figuring out
how it should all be aggregated
Notes: Andrew indicated there is quite a bit of manual work that takes
place to obtain this data and make it available on amsat.org. I haven't
solved this problem, I still need to do my homework here :-)
B) Determining the format of the amsat specific tags to be used in the xml
Notes: I mentioned the idea to Andrew G. and David J briefly over email
and started proposing some ideas. I attached a sample rss xml file to
this email. This is by no means comprehensive or complete, but simply
exists to provide some insight into what the custom tags could
potentially look like. If i've left anything out that may be of
interest, please let me know.
C) Getting all the data into the RSS feed to start out
Notes: I created a python script that walks through all the amsat.org
satellite status pages and scrapes the summary and mode data. It then
aggregates it all into a text file for now. I can very easily use a
template engine to get this data into the rss xml format, once it's
agreed upon. This should drastically reduce the amount of effort to get
this feed started.
To give everyone on the list an idea of what i'm talking about here I
attached both the sample rss file and status.txt file generated by my
script. The status.txt file as I mentioned is just what the "scraped
out" data looks like. This file would then be translated into the final
rss xml format to get things started. If you have any questions or
comments, do not hesitate to contact me. The main question I would like
to have answered by the community are:
1) Is anyone in the community interested in an rss feed like this?
2) Would anyone have a use for sat summary, mode and keps data being
provided in such a way?
Let me know,
Joseph Armbruster, KJ4JIO
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End of AMSAT-BB Digest, Vol 4, Issue 170
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