Author: SM0TGU

Det pgr nu tester att frska kontrollera AO-7, ls mer nedan:
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I guess it s time for me to step forward out of the shadows. The behavior you re observing is being caused by me, N1JEZ. I m the so called Covert AO-7 Command Operator .

Before everyone gets all crazy, please let me try and explain a few things.

First, I asked to remain covert for a period of time because I did not want to have to deal with the inevitable flood of email that will result from my identity being known. At the time, I was in a critical phase of trying to command the bird and needed to concentrate on that task. There were a number of technical hurdles to overcome, not the least of which is dealing with 30 year old stuff.

I know I m going to get a lot of email, so I ve put together the following FAQ. Please read through it. Hopefully it will answer some of your questions and avoid you sending them to me.

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AO-7 FAQ

Q: Tell me how the commands work.
A: Sorry, I _will not_ discuss any of the command details. Don t even ask.

Q: Tell me how the hardware works.
A: Sorry, I _will not_ discuss any of the command details. Don t even ask.

Q: What are the plans for AO-7.
A: I haven t foggiest! My job is to investigate what commands work and what commands don t after 21 years. It s really exciting, but tedious work. Imagine the thrill of seeing this antique accept your first command after all these years! For me, this is similar to the experience I had not long ago hearing the AO-40 24 GHz K Band beacon the first time. I ve gone from techno to retro in a short period of time.

Q: I m doing a satellite demo next Monday night. Can you make sure AO-7 is in Mode B?
A: Sorry, as I stated above, my only job is to test various commands.

Q: When it comes to AO-7. I m mad as hell and I m not going to take it anymore! Just leave it alone!
A: OK, take one of your little yellow pills and then send off a note to your favorite AMSAT official. Honestly, if you have concerns, voice them to Robin, VE3FRH or one of the Board of Directors. Everyone here is trying to do the right thing.

Q: How can I help?
A: Of most interest to me is how AO-7 wakes up as it enters sunlight. Also, any observations of simultaneous multiple modes would be most valuable. Yoshi Imaishi, JF6BCC is compiling an excellent list of observations. Please send him whatever you have. jf6bcc@jarl.com
You can view the list at:
http://plaza16.mbn.or.jp/~palau/temp/AO7-mode-report.xls

Q: Can you tell us _anything_ about this satellite?
A: I can tell you that command attempts are successful. I ve only tested a very limited number of functions, but it s very encouraging. I hope to be able to do a write up on all the fun I ve been having. Maybe it will be in the AMSAT Journal or perhaps a presentation at the AMSAT Symposium later this year. (get your tickets now )
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I still have a ton of work to do. So please try and keep the email to a minimum. I ll try and answer what I can.

[ANS thanks Mike Seguin, N1JEZ, for the above information.]

Klla: ANS 202

Bob Bruninga, WB4APR, har lmnat en del info om vad som hnder med PcSat just nu. Har ett utdrag:
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Bob Bruninga WB4APR announced that PCSat has turned DIGI OFF and all 1200 baud TLM off.

Although PCsat has been perfectly usable in the afternoons into early evenings, the satellite is still running the batteries down on every eclipse. So today I thought of one last low power mode I can try so we turned DIGI and TELEMETRY OFF to see if we can make it through just ONE eclipse. That s all we would need to recover PCsat back into a positive power budget.

I will try this for the daytime passes over the USA this week (which will affect the evening passes over Europe).

The lowest power mode of PCsat has been with all BULLETINS and all DIGIpeating turned off. Also we disable 9600 baud 1 minute telemetry as well. Thus the only thing remaining was the once per minute single 1200 baud telemetry packet which is required to keep the heart-beat fail-safe reset timer tickled. What s new, is that we realized that if we switched the 1/min TLM to 9600 baud instead of 1200, we would further reduce the minimum transmit duty cycle in our lowest power mode. Thus halving our transmit current drain.

Unfortunately, our TRANSMIT power is already less than 10% of the overall bus power, so this move will only gain us about 5%, but worth trying… Our minimum transmit average current drain (1 packet per minute) is only about 16 ma out of the nominal 160 ma low power mode. Dropping this in half saves us about 8 ma. Who knows, maybe it is the straw that can give new life to the camel?

Anyway, when PCsat is in this minimum mode, the ONLY thing you will hear will be a once a minute half second noise burst (9600 bd TLM) and nothing else.

Mera info p hemsidan:
http://www.ew.usna.edu/~bruninga/pcsat.html
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Klla: ANS 202

Hej! satellitvnner

Av en hndelse s snurrade jag frbi 145 830 och hrde packet trafik, snabbt p med modemet och det var PCSAT-11 som snde, jag noterade EB3GEK och W3ADO-1 i meddelandet.

Det gr ju rtt mkt packet trafik frn ISS ocks som man kan titta p, frekvens 145800. Jag satt ven och lyssnade efter AO10 i kvll nr jag tyckte det borde vara ett bra lge men det r fortfarande tyst. (jag saknar en mode B sat i DX bana!!!)

Fr vrigt s fr jag det till att man borde kunna se ISS i slutet p mnaden som afton stjrna, runt den 28/7 om mitt program stmmer.

Avslutningsvis s kan jag nmna att jag krde I2FAK via EME med 100 watt och 2 antenner i gr kvll p random, visserligen har han 24 antenner!! men i alla fall, det r ju en otroligt svag signal som kommer tillbaka till honom, testa grna ngon gng med era Oscar stationer det gr att hitta honom runt 144038 vid aktivitets helgerna.

73 Hkan SM7WSJ

Klla: Hkan SM7WSJ via mailinglistan

Info frn SM0AIG:

Vid passagen 2015z ikvll var mode A aktivt med beacon p 29502 kHz. Svrlst telemetri pga QRN. Inga stationer igng trots att passbandet fungerade med fotavtryck som mot slutet tckte bde Kanada och USA:s stkust. Kunde hra min egen CW p nedlnken trots endast 10W till gp p 145.940 vilket landade p ca 29.490 med ngot svajig tonhjd.

Annars dliga passager utom 1428z med AO-7 i hgform p mode B. Kraftig beacon och starka signaler p passbandet. Kanonbra retur p CW men bara folk igng p SSB. QSO med DD9ZO.

Det finns en utmrkt telemetridekoder fr AO-7 i form av ett Excel-ark. Man fr in de tv sista siffrorna i varje grupp i kolumnen TLM count och fr direkt det analoga vrdet p olika parametrar. Som referens r inlagd telemetrin frn den allra frsta sndningen som upptcktes av G3IOR. Eftersom denna BB inte accepterar bilagor, kan jag bara snda den direkt till den som r intresserad. Liksom telemetri frn 1428-passagen.

Ingemar / SM0AIG

Lnk till Excel-arket:
http://www.amsat.org/amsat/ftp/software/spreadsheet/AO7tlmSS.zip
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Klla: SM0AIG via mailinglistan

Frst info frn Henry/SM5BVF:

OSCAR-7 :s telemetri hrs bra p 145,975 ca fr den som r intresserad.
Kepler enl. fljande:

AO-07
1 07530U 74089B 02167.52996888 -.00000029 00000-0 10000-3 0 935
2 07530 101.7955 212.2077 0012102 193.4285 166.6467 12.53558681262239

Satellite: AO-07
Catalog number: 07530
Epoch time: 2167.52996888
Element set: 93
Inclination: 101.7955 deg
RA of node: 212.2077 deg
Eccentricity: 0.0012102
Arg of perigee: 193.4285 deg
Mean anomaly: 166.6467 deg
Mean motion: 12.53558681 rev/day
Decay rate: -2.9E-07 rev/day^2
Epoch rev: 26223

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Sedan frn Ingemar/SM0AIG:

En ganska fantastisk historia

AO-7 sndes upp 1974 och fungerade bra fram till 1981 d den avsomnade pga kortslutning i ett eller flera batterielement. Nu har tydligen batterierna torkat ut s att kortslutningen slppt och den har pltsligt brjat snda s snart den r solbelyst.

Det var Pat, G3IOR som p midsommarafton av en ren slump upptckte telemetrisignalerna p 2 meter – frst utan att ha en aning varifrn signalerna kom. Nu har man ocks upptckt att ven transpondern fungerar.

Flera stationer i USA har redan krt QSO via den teruppstndne Lazarus alias AO-7. Mode B: upp ca 432.120-180 och ned 145.920-980 inverterande. Hittills verkar ingen ha vgat sig ut p passbandet i Europa. Uppfrekvensen r kanske ngot tveksam fr knsliga naturer.

Telemetrin p 145.975 +/- doppler snds enligt fljande schema:

1aa 1bb 1cc 1dd
2aa 2bb 2cc 2dd
3aa 3bb 3cc 3dd
4aa 4bb 4cc 4dd
5aa 5bb 5cc 5dd
6aa 6bb 6cc 6dd
Hi Hi

Den som r lagd t knep och knp kan dekoda med hjlp av bifogad bmp. Nedan r ngra exempel frn passagen 15:30z idag:

> 100 145 176 156
> 297 245 200 254
> 370 34x 328 354
> 453 455 450 451
> 542 501 553 529
> 60x 601 601 651
>
> 100 166 179 156
> 297 263 201 254
> 376 368 331 354
> 448 455 449 451
> 541 501 552 529
> 60x 601 601 651

Halvskaplig mottagning p en gp. AO-7 snder s snart den lmnar jordskuggan och vxlar mellan snabb och lngsam cw vid olika pass. Ingen har hittills lyckats hra beacon p 10 meter och 70 cm. Den hade p sin tid ven en transponder i mode A: 145.850-950 upp och 29.400-500 ned.

73 de SM0AIG
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Lnk till telemetrinyckeln:
http://members.aol.com/rogerkola/chart.bmp

Klicka hr fr att se nyckeln direkt (185 kBt):
http://amsat-sm.mailsystem.net/bilder/misc/ao-7_chart.gif
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Info frn AMSAT-NA

Klla: SM5BVF och SM0AIG