AO-07, Lazarus since 1974!
(21 Jun 2002) Lazarus?
(22 Jun 2002) AO-7 info from Jan
(22 Jun 2002) AO7??
(23 Jun 2002) Re: Oscar 7
(23 Jun 2002) AO-7 telemetry format
(23 Jun 2002) AO 7 Technical data
(23 Jun 2002) OSCAR 7 Telemetry decoding info
(23 Jun 2002) Re: AO7 telemetry today
(23 Jun 2002) AO-7 history and info
(24 Jun 2002) Re: AO-07 PARADOX?
(24 Jun 2002) Oscar-7 and the ITU
(27 Jun 2002) AO-7 Telemetry (from 1975)
(02 Jul 2002) AO-7 telemetry analysis
(03 Jul 2002) OSCAR 7 Orbit Number, Add 100,000
(04 Jul 2002) AO-7 CW beacon wave file
(13 Jul 2002) AO-7 just 100000 on 22 Sep 1996
(22 Jul 2002) AO-7 telemetry analysis #2
(08 Oct 2003) AO-7 CW beacon
(07 Sep 2005) AO-07 recorded
(27 Nov 2005) AO-07 CW carrier FFT image
(05 Jan 2006) AO-07 CW telemetry
(15 Nov 2006) AO-07 healthy CW
(02 Mar 2009) AO-7 RTTY beacon
--------------------------------------------------------------------------
Subject: [amsat-bb:59478] Re: Lazarus?
From: "pat gowen"
To: amsat-bb
Date: Fri, 21 Jun 2002 22:30:54 +0100
I have just come across something most remarkable this Friday 21st June
evening. Checking out interlopers in our 145.800 - 146.000 MHz space
band with a new vertical now atop my 60' tower and working like magic,
at 1728 UTC I came across a beacon at S.7 sending slow 8 -10 wpm CW on
145.973.8 MHz. It slowly Dopplered down to 145.970 MHz before going out
at 1739 UTC. A full run of TLM went: -
Hi Hi
100 176 164 178
280 262 200 254
375 358 331 354
453 454 461 459
541 501 552 529
600 600 601 651
Hi Hi
It sounded VERY familiar, but, I'm dammned if I can recall which one it
was. Obviously an OSCAR, but which had the callsign W3OHI? Oscar-6, 7,
or 8 ? I think it was OSCAR-6. If so, we have a new longevity record,
even beating RS-1 !
The beacon peaked S9 and there were S7 burbles some 10 - 20 KHz below
the beacon, FSK'ing slightly as the beacon keyed. At times the beacon
took on a rough quality, wobbling in frequency, then coming back strong
and quite stable again. Going by the QSB rate it had about a 1 minute
spin.
Could any veteran keen observers (who might look for it) please tell me
what it was, as I feel sure that any old time AMSAT OSCAR devotee may
have a far better memory than I !
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Subject: [amsat-bb:59513] AO-7 info from Jan
From: Jim White
To: amsat-bb
Date: Sat, 22 Jun 2002 16:00:08 -0600
Folks,
Following are two messages from Jan King regarding the signal Pat heard
the other night on 145.975. It clearly was OSCAR-7. Jan's messages
pretty much speak for themselves. Pretty amazing story.
Jim
My God, I can't believe what Pat was hearing. It has to be AMSAT-OSCAR-7
according to the frequency. AO-6 had a 70 cm beacon, which failed fairly
quickly after launch, and a 2m up/10m down transponder (the original Mode A
transponder). AO-8 had another Mode A transponder and the first Mode J
transponder built by the Japanese. That was, of course, backwards
from Mode B or 2m up/70 cm down. But, AO-7 had both a Mode A and a MODE B
transponder. Mode B had a downlink on 2m. So, of those three satellites,
AO-7 is the only one that had a downlink on 2m. Let me go out to the garage
and check the frequency.
--------- Time Passed Here.---------
Well, the garage files aren't what they once were. Most of the original
files were there but, the Karl Meizer - Mode B file is missing! Damn. Also
missing are the log books, which are historically valuable. The logs aren't
lost. I packed them away with my office stuff somewhere in my garage boxes
which second as a warehouse - so I wouldn't lose them. :-( But, I knew I
had lots of stuff that would tell the frequency plan. The first thing I
found as I was looking was an old ARRL booklet called, "Getting to Know
OSCAR from the Ground Up." I seem to have been a co-author. Hmmm. Don't
even remember it. The transponder had an uplink at 432.125 MHz to 432.175
MHz. The passband was inverting and a little less than 50 kHz wide. The
downlink passband was from 145.925 to 145.975 MHz. THE BEACON WAS AT
145.975 MHz. If I can find the log books I can tell you how far off the
nominal frequency the beacon was as measured back in November 1974 just
before launch. So Pat was hearing AO-7, 24 years after it died! Whew!!
Here's probably what's happening. That thing has a good set of arrays and
the first BCR (battery charge regulator) we ever flew. It's the first
spacecraft we ever had that was capable of overcharging the battery. When
the battery failed the cells began to fail short. One cell after another
failed and the voltage measured on telemetry began to drop. So, the cells
were clearly failing SHORT. Now, after all these years, what happens if any
one of the cells loses the short and becomes open? Then, the entire power
bus becomes unclamped from ground and the spacecraft loads begin to again be
powered but, this time only from the arrays. Now you have a daytime only
satellite but, each time the sun rises at the spacecraft you have a random
generator that either turns on Mode A or Mode B or whatever it wants. So,
occasionally that 70cm/2m transponder transmitter and beacon must least
work. From what you have told me (and without going back and decoding the
old telemetry equations) I can tell you that the following things work in
that spacecraft: The arrays, the BCR, the ISR (instrumentation switching
regulator), the Mode B transmitter and beacon injection circuitry, the Morse
Code telemetry encoder, and the voltage reference circuitry. The latter I
know is working because the last telemetry value is 651. The "6" is just the
row number of the telemetry value but the 51 means that the 1/2 volt
reference is measuring 0.51 volts. I know that telemetry equation by heart
since it was used as the calibration value for the rest of the telemetry
system. So the telemetry has a fair chance of being decoded and making some
sense!!! How about that, man?
Jim that's all amazing for someone who was as close to that thing as I was.
You must remember, that spacecraft was built in my house (in a basement
laboratory) in Lanham, Maryland. Werner and Karl were putting the finishing
touches on that transponder when Ian, my son was being born in the upstairs
bedroom. That afternoon Donna and I went to the hospital to have the baby
while Karl and Werner continued final debugging! So, it doesn't get much
more personal than that.
As the man said, "It's most remarkable." You can post this to the AMSAT-bb
if you want.
73's,
Jan W3GEY
AMSAT-OSCAR-7 Project Manager :-)
Well Jim,
G3IOR's telemetry frame is interesting. Apparently he did hear the AO-7 Mode
B beacon tonight.
I got out my December 1974 and looked up the telemetry equations for the
Morse Code Telemetry Encoder and what I found is in the attached
spreadsheet.
I'm blown away. Most of this stuff makes pretty good sense. In particular,
the temperatures make sense and I would have guessed that they would be the
most sold IF the reference voltage held (which it did). Interpreting some of
this for those who may not understand or don't remember, the telemetry says
the spacecraft was in Mode B; all the other beacons and Mode A were off. It
is possible that the thing had just turned on because the old 24 hour timer
just reset it to Mode B. The damn thing may think it is still on an every
other day cycle. The power output of the transponder is 1.16 watts which
may mean it is transmitting white noise plus beacon power. That seems about
right, but a little low as I recall. The instrumentation switching regulator
is in the middle of it's normal range and seems to be working fine. The
internal temperatures are around 15 deg. C; the external temperatures are
around 5 C and the transponder PA temp, which should be the warmest - IS -
it's 35.1 deg. C. The array current value is bust. I think maybe it always
was. Need to look for some old telemetry to confirm that. The array
current calibrations looks off. The array currents are in the normal range
but all four show current. This can't be. Only two at a time should show
current. Without a battery on line, this is entirely possible. The big
find is that the battery voltage telemetry shows a voltage of 13.9 volts.
Normal is 13.6 to 15.1 volts. So that would suggest the battery was normal
BUT, the 1/2 battery voltage is measuring only 5.8 volts. That can't be.
This imbalance probably means that the 5.8 volts is the correct value for
the lower half of the battery (which is a low value for that half, if the
cells were normal - they are probably not) and there is a break somewhere in
the upper 1/2 of the battery string. My guess is the indicated voltage is
really what the BCR is putting out with only the spacecraft load as a real
load and the battery string has an effective break (or a pretty high
resistance) somewhere in the upper half.
So, this old war horse of a spacecraft seems to have come back from the dead
if only for a few moments. And it is telling us, that even in a 1460 km
high orbit a cheap spacecraft built by a bunch of hams, without very many
high rel parts and without designing for a radiation dose like this, can
last for 27+ years in space as far as a majority of it's electronics is
concerned. Even the damn precision reference voltage regulator is still in
calibration! Pitty Pat did not recognize his old friend when he saw him
again.
Well Jim, you made my day!
73's,
Jan bottom top
Subject: [amsat-bb:59517] AO7??
From: Perry Yantis
To: amsat-bb
Date: Sat, 22 Jun 2002 20:35:40 -0400
I put the newer keps in my Nova program that was posted on the Amsat
BBs for AO-7. Then tonight I listened for AO-7. At 2359 gmt on June 22,
2002 I started hearing a beacon at 145.97550 here in em89 south of
Columbus, Ohio.
It started with HI HI then send a bunch of 3 digit numbers, but no
satellite ID. I then went to 145.953 and input a signal at 432.143
and I heard myself very loud.
It was so loud that I was sure it was a harmonic in my TS2000x.
But when Nova said the satellite was getting to a lower elevation my
signals started getting weaker.
Then just about the time Nova said AO-7 was gone it was !!!!
I then tried again to input on 432.143 and tuned around not hearing
a sound on 145.953 (I tuned the general area of that frequency).
So I don't think it was a harmonic in my TS2000x after all.
But it sure was a strong signal I heard !!!!!!!!
But was it really AO-7, or another satellite with a similar orbit ????
It will be interesting to find out, ha, ha.
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Subject: Re: Oscar 7
From: Mineo Wakita
To: amsat-bb
Date: Sun, 23 Jun 2002 11:22:40 +0900
I heard CW from AO-7 in Japan.
AO-7, 145.973 MHz +/- doppler
00:26-00:47 UTC, June 23, 2002
> 455 460 459 541 501 552 530 600 601 601 604 HI HI
> 180 182 106 141 281 201 270 239 ... ...
>
> http://www.ne.jp/asahi/hamradio/je9pel/20623a07.wav
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
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Subject: AO-7 telemetry format
From: Mineo Wakita
To: amsat-bb
Date: Sun, 23 Jun 2002 16:19:31 +0900
AO-7 telemetry format:
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
then these data are validly when Ch6D is one of 649,
650 or 651.
G3IOR/Pat Gowen wrote at 22:30:54 +0100, 21 Jun 2002,
100 176 164 178
280 262 200 254
375 358 331 354
453 454 461 459
541 501 552 529
600 600 601 651
Hi Hi
So these data are validly. And,
Ch3A indicate 10 NiCd Vol = 0.1*75 + 6.4 = 13.9 [V]
Ch3B indicate 5 Nicd Vol = 0.1*58 = 5.8 [V]
http://www.amsat.org/amsat/sats/n7hpr/ao7_tlm.html
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Subject: [amsat-bb:59579] AO 7 Technical data
From: "Davidoff, Martin", K2UBC
To: AMSAT-BB
Date: Sun, 23 Jun 2002 14:16:09 -0400
AMSAT-OSCAR 7
Beacons
29.502 MHz (200 mw) Used in conjunction with Mode A
145.972 MHz (200 mw) Used in conjunction with Mode B and C
[low power Mode B]
435.100 MHz (intermittent problem -- switches between 400 mw and 10mw)
2304.1 MHz (40 mw) Must be commanded on. Auto off after 15 minutes.
Requires STA to operate.
Transponder I: Mode A (2m/10m)
type: linear, non-inverting
uplink passband: 145.850 - 145.950 MHz
downlink passband: 29.400 - 29.500 MHz
translation equation:
downlink (MHz) = uplink (MHz) - 116.450 MHz +/- Doppler
output power: 1.3 watts PEP (start of life)
Transponder II: Mode B (70cm/2m) and Mode C (low power)
type; linear, inverting
uplink passband: 432.125 - 432.175 MHz *See Note
downlink passband: 145.975 - 145.925 MHz
translation equation:
downlink (MHz) = 578.100 - uplink (MHz) +/- Doppler
output power: 8 watts PEP Mode B(start of life!), 2.5 watts PEP Mode C
*Note: Due to changes in Radio Amateur Service and Radio
Amateur Satellite Service there are questions as to
legality of US Amateurs transmitting to AO-7 on this frequency.
bottom top
Subject: [amsat-bb:59580] OSCAR 7 Telemetry decoding info
From: "Davidoff, Martin", K2UBC
To: Amsat-BB
Date: Sun, 23 Jun 2002 13:27:03 -0400
AMSAT BB Readers may be interested in the decoding equations which
follow. [Please post any updates or corrections]
Also,
IF 1. Speculation that long term chemical changes in one
or more battery cells have led to increased cell
resistance enabling the spacecraft to operate while
in sunlight are correct and
2. Reports indicating that beacons, telemetry systems,
and possibly transponders are operating
THEN The prognosis for long term spacecraft operation are excellent.
If any of the old command stations are reading this I suggest that
they step in and test the command system!
Finally, the orbit is very circular and very stable but some good
orbital elements would help.
CHNL Parameter Measurement Range Calibration Equation
---- --------- ----------------- --------------------
1A Total Solar Array Current 0 to 3000 ma I = 29.5 N (ma)
1B +X Solar Panel Current 0 to 2000 ma I = 1970 - 20N (ma)
1C -X Solar Panel Current 0 to 2000 ma I = 1970 - 20N (ma)
1D +Y Solar Panel Current 0 to 2000 ma I = 1970 - 20N (ma)
2A -Y Solar Panel Current 0 to 2000 ma I = 1970 - 20N (ma)
2B RF Power Out 70cm/2m 0 to 8 watts P = 8(1 - 0.01N)^2 (watts)
2C 24 Hour Clock Time 0 to 1440 min. t = 15.16N (min)
2D Battery Charge/Discharge -2000 to 2000 ma I = 40(N - 50) (ma)
3A Battery Voltage 6.4 to 16.4 V V = 0.1N + 6.4 (volts)
3B Half-Battery Voltage 0 to 10 V V = 0.10N (volts)
3C Bat. Chg. Reg. #1 0 to 15 V V = 0.15N (volts)
3D Battery Temperature -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
4A Baseplate Temperature -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
4B PA Temp. 2m/10m -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
4C +X Facet Temp. -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
4D +Z Facet Temp. -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
5A PA Temp. 70cm/2m -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
5B PA Emit. Current 2m/10m 0 to 1167 ma I = 11.67N (ma)
5C Module Temp. 70cm/2m -30 to +50 deg. C T = 95.8 - 1.48N (deg.C)
5D Instrument Sw. Regulator
Input Current 0 to 93 ma I = 11 + 0.82N (ma)
6A RF Power Out 2m/10m 0 to 10,000 mw P = (N^2)/1.56 (mw)
6B RF Power Out 70 cm 0 to 1,000 mw P = 0.1(N^2) + 35 (mw)
6C RF Power Out 13 cm 0 to 100 mw P = 0.041(N^2) (mw)
6D Midrange Telemetry Calib. 0.500 V V = 0.01N(0.50 +/- 0.01) (V)
bottom top
Subject: [amsat-bb:59591] Re: AO7 telemetry today
From: Gilbert Mackall gmackall, N3RZN
To: Robert Turlington, G8ATE
Cc: amsat-bb
Date: Sun, 23 Jun 2002 18:14:13 -0400
Here is a decode:
1A: Total Solar Array Cur 0.00 ma
1B: +X Solar Panel Cur 430.00 ma
1C: -X Solar Panel Cur 390.00 ma
1D: +Y Solar Panel Cur 1030.00 ma
2A: -Y Solar Panel Cur 1810.00 ma
2B: RF Pwr. out 70/2 0.77 watts
2C: 24-Hr Clock Time 30.32 min
2D: Batt Chg/Dischg Cur 160.00 ma
3A: Battery Voltage 13.90 volts
3B: High-Batt Voltae 6.40 volts
3C: Bat. Chg. Reg. #1 4.65 volts
3D: Battery Temp. 15.88 c
4A: Baseplate Temp. 30.68 c
4B: PA emp. -2/10 Rptr 14.40 c
4C: +X Facet Temp. 23.28 c
4D: +Z Facet Temp. 17.36 c
5A: PA emp. -70/2 Rptr 35.12 c
5B: PA Emit. Cur. 2/10 11.67 ma
5C: Modul Temp 70/2 18.84 c
5D: Instr SW. reg. Input Cur. 34.78 ma
6A: RF Pwr out-2/10 0.00 mw
6B: RF Pwr Out-435 35.10 mw
6C: RF Pwr Out-2304 0.04 mw
6D: Midrange TLM Calibration 0.51 v
1A: Total Solar Array Cur 0.00 ma
1B: +X Solar Panel Cur 290.00 ma
1C: -X Solar Panel Cur 150.00 ma
1D: +Y Solar Panel Cur 610.00 ma
2A: -Y Solar Panel Cur 1170.00 ma
2B: RF Pwr. out 70/2 6.48 watts
2C: 24-Hr Clock Time 1000.56 min
2D: Batt Chg/Dischg Cur -1880.00 ma
3A: Battery Voltage 6.60 volts
3B: High-Batt Voltae 0.20 volts
3C: Bat. Chg. Reg. #1 3.30 volts
3D: Battery Temp. 17.36 c
4A: Baseplate Temp. 91.36 c
4B: PA emp. -2/10 Rptr 41.04 c
4C: +X Facet Temp. -41.84 c
4D: +Z Facet Temp. 4.04 c
5A: PA emp. -70/2 Rptr -3.36 c
5B: PA Emit. Cur. 2/10 81.69 ma
5C: Modul Temp 70/2 7.00 c
5D: Instr SW. reg. Input Cur. 61.02 ma
6A: RF Pwr out-2/10 830.77 mw
6B: RF Pwr Out-435 612.60 mw
6C: RF Pwr Out-2304 13.28 mw
6D: Midrange TLM Calibration 0.62 v
1A: Total Solar Array Cur 0.00 ma
1B: +X Solar Panel Cur 750.00 ma
1C: -X Solar Panel Cur 150.00 ma
1D: +Y Solar Panel Cur 830.00 ma
2A: -Y Solar Panel Cur 1870.00 ma
2B: RF Pwr. out 70/2 1.34 watts
2C: 24-Hr Clock Time 591.24 min
2D: Batt Chg/Dischg Cur -1200.00 ma
3A: Battery Voltage 12.70 volts
3B: High-Batt Voltae 5.30 volts
3C: Bat. Chg. Reg. #1 3.90 volts
3D: Battery Temp. 17.36 c
4A: Baseplate Temp. 51.40 c
4B: PA emp. -2/10 Rptr 94.32 c
4C: +X Facet Temp. 21.80 c
4D: +Z Facet Temp. 17.36 c
5A: PA emp. -70/2 Rptr 26.24 c
5B: PA Emit. Cur. 2/10 0.00 ma
5C: Modul Temp 70/2 20.32 c
5D: Instr SW. reg. Input Cur. 33.14 ma
6A: RF Pwr out-2/10 2.56 mw
6B: RF Pwr Out-435 35.00 mw
6C: RF Pwr Out-2304 0.04 mw
6D: Midrange TLM Calibration 0.51 v
1A: Total Solar Array Cur 0.00 ma
1B: +X Solar Panel Cur 1410.00 ma
1C: -X Solar Panel Cur 170.00 ma
1D: +Y Solar Panel Cur 510.00 ma
2A: -Y Solar Panel Cur 1190.00 ma
2B: RF Pwr. out 70/2 1.10 watts
2C: 24-Hr Clock Time 15.16 min
2D: Batt Chg/Dischg Cur 160.00 ma
3A: Battery Voltage 13.30 volts
3B: High-Batt Voltae 2.70 volts
3C: Bat. Chg. Reg. #1 3.75 volts
3D: Battery Temp. 15.88 c
4A: Baseplate Temp. 24.76 c
4B: PA emp. -2/10 Rptr 14.40 c
4C: +X Facet Temp. 20.32 c
4D: +Z Facet Temp. 17.36 c
5A: PA emp. -70/2 Rptr 26.24 c
5B: PA Emit. Cur. 2/10 11.67 ma
5C: Modul Temp 70/2 18.84 c
5D: Instr SW. reg. Input Cur. 33.96 ma
6A: RF Pwr out-2/10 0.00 mw
6B: RF Pwr Out-435 35.10 mw
6C: RF Pwr Out-2304 0.00 mw
6D: Midrange TLM Calibration 0.50 v
On Sunday, June 23, 2002, at 12:15 PM, Robert Turlington wrote:
> Hi all
> took the following Oscar7 CW telemetry on the 2mtr downlink today at
> about 1535 utc using Hamscope. I also managed momentarilr to hear my
> own downlink before taking the Tlm
>
> hi hi
> 100 177 179 147
> 208 269 202 254
> 375 364 331 354
> 444 455 449 453
> 541 501 552 529
> 600 601 601 651
> hi hi
> 100 184 191 168
> 240 210 266 203
> 302 302 322 353
> 403 437 493 462
> 567 507 560 561
> 636 676 618 662
> hi hi
> 100 161 191 157
> 205 259 239 220
> 363 353 326 353
> 430 401 450 453
> 547 500 551 527
> 602 600 601 651
> hi hi
> 100 128 190 173
> 239 263 201 254
> 369 327 325 354
> 448 455 451 453
> 547 501 552 528
> 600 601 600 650
Cf.
http://www.amsat.org/amsat/ftpsoft.html#ss
http://www.amsat.org/amsat/ftp/software/spreadsheet/AO7tlmSS.zip
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Subject: [amsat-bb:59609] AO-7 history and info
From: Keith N6ORS
To: amsat
Date: Sun, 23 Jun 2002 18:53:04 -0700
AMSAT-OSCAR 7 REFERENCE DATA:
Frequencies:
Two to ten meter translator.
Input 145.850 to 145.950 mHz
Output 29.40 to 29.50 mHz
70 cm to two meter translator.
Input 432-125 to 432-175 offs
Output 145.975 to 145.925 mHz
Output passband is INVERTED.
Beacon output at 145.975 mHz
Additional beacons at 435.1 mHz and 2304.1 mHz (The FCC has notified AMSAT
that the 2304 mHz beacon should be "prevented from transmitting" until
further notice.)
Operating Modes:
Mode A. 2 to 10 motor translator ON. 29.502 mHz beacon 02
(transmitting 20 wpm Mores code telemetry or codestore info). 435.1
mHz beacon operable (normally ON. transmitting 850 Hz FSK teletype
telemetry).
Mode B. 70 cm to 2 meter translator ON (high power nods). 145.975
mHz beacon ON (modulated as per 29*502 beacon).
Mode C. 70 cm to 2 meter translator ON (quarter power mode). 145.975
mHz beacon ON per mode B.
Mode D. Recharge mode. Both translators OFF. 435 mHz beacon operable
(Commanded on for telemetry readout)
Operating Schedule: (Planned after initial spacecraft checkout)
Mode A. Sunday, Tuesday and Friday
Mode B. Monday, Thursday and Saturday
Mode D or special experiments on Wednesday
Planned Orbit:
Similar to that of OSCAR 6; 1460 km altitude circular orbit, 102
degree inclination (retrograde, sun-synchronous orbit), period or
115 minutes, about 1/2 orbit (1 hour) out of phase with the OSCAR 6
orbit.
For additional info, see Feb 1974 QST. The following information Is from
AMSAT NEWSLETTER for Sept 1974:
SPACECRAFT DESCRIPTION
AMSAT-OSCAR 7 contains two basic experimental repeater packages, redundant
command systems, two experimental telemetry systems, and a store-and-forward
message storage unit. The spacecraft in solar powered, weighs 65 pounds, and
has a three-year anticipated lifetime. It contains beacons on 29.50, 145.98,
435.10 and 2304.1 MHz.
Communications Repeaters
Two types of communications repeaters are aboard the spacecraft, only one of
which operates at a time. The first repeater is a higher power, two-watt
version of the one-watt two-to-ten motor linear repeater that flow on the
OSCAR 6 mission. This nit receives uplink signals between 145.85 and 145.95
MHz, and retransmits them between 29.4 mid 29.5 MHz an the downlink. A 200
milliwatt telemetry beacon provides telemetry data on 29.502 MHz.*
Approximately -100 dBm is required at the repeater input terminals for an
output of 1 watt. This corresponds to an eirp from the ground of 90 watts
for a distance to the satellite of 2,000 miles and a polarization mismatch
of 3 dB.
The second repeater, constructed by AMSAT Deutschland e.V., AMSAT's
affiliate in Marbach, West Germany, is a 40-kHz* bandwidth linear repeater.
It employs an 8-watt PEP power amplifier using the envelope elimination and
restoration technique to maintain linear operation over a wide dynamic range
with high efficiency. This repeater has an uplink from 432.125 to 432.175
MHz, and a downlink from 145.925 to 145.975 MHz. Since the uplink band in
shared with the radiolocation service, an experimental pulse suppression
circuit is incorporated in the repeater to reduce the effects of wideband
pulsed radar interference in the uplink. Developmental versions of this
repeater have flown in high-altitude balloon experiments in Germany, and
aircraft flight tests of the repeater prototype unit. A 200 milliwatt
telemetry beacon on 145.975' provides telemetry data. Approximately So
W.*eirp is required to produce 3 watts of repeater output at a range of
2,000 miles assuming.& polarization mismatch of 3 db.
The two repeaters are operated alternately by means of a timer arrangement,
but repeater selection and output power control can also be accomplished by
ground command. Each of the repeaters includes a keyed telemetry beacon at
the upper edge of the downlink passband to provide housekeeping data and to
provide a frequency and amplitude reference marker to assist the amateur in
antenna pointing, Doppler frequency compensation, and setting uplink power
level. The cross-band 146-to-29.5 and 432-to-146 KNO design of the two
repeaters will permit the amateur to monitor his own downlink signal easily,
and consequently, he can adjust his power and frequency to continually
compensate for changing path loss, repeater loading and Doppler shift.
Command System
Redundant command decoders of a design similar to the unit proven highly
successful in OSCAR 6 will be flown. The decoder has provisions for 35
separate functions, and is designed to provide a reliable means of
controlling the emissions of the repeaters, beacons and other experiments
aboard the spacecraft.
Telemetry and Message Storage Systems
AMSAT-OSCAR 7 contains two experimental telemetry systems designed for use
with simple ground terminal equipment. The first system, developed by the
WIA-Project Australis group in Australia, telemeters 60 parameters in 850-Hz
shift, 60 WPM five-level Baudot teletype code to permit printout on standard
teletype equipment in a format readily convertible for direct processing by
small digital computer. The second system telemeters 24 parameters as
numbers in standard Morse code and can be received with pencil and paper.
This system was used on OSCAR 6 and proved highly successful as a reliable
means of obtaining real-time telemetry data.
An experimental Morse code message storage unit, Codestore, capable of
storing and repeatedly retransmitting 18-word More& code messages loaded by
ground stations in also aboard AMSAT-OSCAR 7. This unit was first flown on
OSCAR 6.
The teletype telemetry encoder amplitude-modulates telemetry beacons on
29.50 MHz (200 mw), 145.98 MHz (200 mw) and frequency-shift keys the beacon
on 435.10 MHz (300-400 mw), as selected by ground command. The Morse code
telemetry encoder and Codestore message storage unit directly key these
beacons as selected by ground command.
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Subject: [amsat-bb:59614] Re: AO-07 PARADOX?
From: "Tom Clark (W3IWI)"
To: amsat-bb
Date: Mon, 24 Jun 2002 00:15:31 -0400
> The last news on AO-07 was that the solar cell come shorted
> due to battery weekness, How is it possible
> to solar cell to unshorted themself and let battery recharged
> after so many years?
A standard mode for a NiCd battery to fail is for a cell to become short
circuited. When AO-7 died years ago, the telemetry showed that several cells
became shorted, and then the satellite went silent. At the time the
spacecraft was running hot (about 40 C) and we felt that the cells failed in
the "cooked" mode.
Now we speculate that (at least) one of the shorted cells has acted like a
fuse, becoming an open circuit. If this is the case, then the satellite is
running only on solar power, and then only in sunlight.
If this is true, then the satellite turns itself on/off each orbit as it
enters sunlight. The mode it chooses to select is probably random.
It would be interesting if the folks on AMSAT-BB would confirm that the
satellite only operates in sunlight. Here is a simple way to know if the
satellite is in sunlight: Look at a graphical view of the visibility circle
on a map that also includes the sunrise/sunset line. If any part of the
coverage circle lies inside the daylight area, then the satellite sees the
sun.
Here I used IT and loaded the KEPS that have appeared on AMSAT-BB. I select
[2] Map View and the AO-7 satellite. To see the satellite move rapidly hit
[F] and then use the [space bar] to toggle fast time on/off. Then you can
read the time that the satellite sees the sun or is eclipsed.
For any of the AMSAT-BB folks: do you have ANY instance of being able to
hear/work AO-7 when it is dark?
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Subject: [amsat-bb:59680] Oscar-7 and the ITU
From: "Tom Clark (W3IWI)"
To: "AMSAT BB (E-mail)"
Date: Mon, 24 Jun 2002 16:20:41 -0400
The question about Oscar-7:
> Aren't the Satellite Sub-Bands a "Gentleman's Agreement" like
> the FM vs SSB 'agreement'? I don't understand why I couldn't
> use the AO-7 70cm uplink frequency as long as my class of license
> allows me to transmit there. What am I missing here?
The basic is answer is a qualified YES & NO. The reason for the yes/no
ambiguity is that there are two sets of issues involved.
Please -- DON'T SHOOT THE MESSENGER!
-...-
Internationally, all frequencies are allocated by the ITU (International
Telecommunications Union) at a WRC (World Radio Conference). Each nation
then ratifies these allocations as an international treaty. Because of its
unique status, and to keep us on a parallel with all the other services, the
ITU has chosen to define TWO separate relevant services: The AMATEUR RADIO
SERVICE and the AMATEUR SATELLITE SERVICE (I'll call these the ARS and ASS).
Allocations to the ARS are the ones relevant for 99% of all of amateur
radio. Some frequencies are set up on a regional basis (Europe + Africa are
Region 1, the Americas are Region 2, and Asia + Oceania are Region 3). As an
example 2 meters is 144-148 in R2 but is only 144-146 MHz in R1. The 144-146
band is uniform world-wide. In some areas, especially in the VHF-UHF
spectrum, some allocations are not even region-wide; the UK has a 70 MHz 4M
band, the US has the 222-225 MHz band.
When the ITU established the ASS in the 1970's, they allocated to amateur
satellites all the exclusive world-wide amateur bands, including 21-21.45,
28-29.7 and 144-146 MHz (no, neither 50 nor 222 MHz is on the list!). But
the 70 cm band is not EXCLUSIVE to amateur radio and, after much dickering
at WRCs in the '70s, the 435-438 MHz band was set aside for the ASS even
though it is shared (with radiolocation services).
When the 435-438 MHz ITU allocation was hatched, AMSAT was already pregnant
with AO-7 "in the basket" using 432.125-.175 MHz, and we were given a "wink
wink" "OK" along with a strong message "but don't ever do it again!". In
some countries (like the UK) there were even more stringent objections and
some countries never permitted to operate.
But you ask "The satellite only listens on 432.15. Why is all this ASS
allocation crap even relevant?". Unfortunately the ITU's ARS vs ASS
distinction applies to BOTH the satellite and the user on the ground.
Therefore when you have a QSO with another amateur on a tropo (or even EME),
you are operating the ARS. As soon as you point your antenna at a satellite,
you are operating in the ASS and are, in principle, subject to different
rules. [Don't yell at me -- I'm only the messenger!]
-...-
I started off by saying that the answer to your question was yes/no, so let
me explain that bipolar bit of thinking. After the ITU allocates a frequency
to the ASS or ARS, then the FCC can give you the right to use it. But the
FCC want Amateur Radio to be self-policing and they don't want to hear of
"turf battles". The FCC refuses to enter the fray on 10 vs 15 kHz frequency
assignments on 2M FM.
With self-policing in mind, amateur radio societies around the world
established the IARU (International Amateur Radio Union). One of the IARU's
functions is to attempt to establish band plans suitable for different
areas. Clearly the band plan need by amateurs in Alaska (thousands of km in
size, with a total population ~500,000) is very different from the
coordination needed in Europe where some countries are only a few hundred km
in size.
In the VHF/UHF range, most problems are pretty local. The main exceptions
are weak signal DX (meteors, tropo, EME etc) and Amateur Satellites. Both of
these have received unique slots in the international bandplans. On 2M,
although the satellites are legally permitted to use the entire 144-146
range, but the IARU bandplans show the 145.8 - 146.0 sub-bands.
-...-
Now back to Oscar-7. When you attempt to use this "Phoenix from the Ashes"
resource in Mode-A there is nothing to worry about. Both legally (in the ITU
context) and morally (in the IARU context), the use of the 2M -> 10
transponder is 100% "clean".
The Mode-B situation is a different matter. You are making use of the
antique AO-7 hardware and are not operating on a legal ITU frequency; and
the frequency is not listed in the IARU bandplans. Whether the FCC (in USA)
or Home Office (UK) or other national authorities will say "wink wink" and
ignore the "accident of history" transgression is uncertain. My gut feeling
is that it will not rise to visibility on their radar screens, and nothing
unpleasant will happen. In terms of "What to do?", I'm reluctant to see the
issue brought up to the FCC; there is a chance their answer would be NO!.
I'm adopting the attitude
"'Tis far better to beg forgiveness rather than asking for permission".
73 de Tom, W3IWI
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Subject: [amsat-bb:59939] AO-7 Telemetry (from 1975)
From: "Davidoff, Martin"
To: AMSAT-bb
Date: Thu, 27 Jun 2002 09:44:22 -0400
To: Anyone following AO-7 Telemetry
The following baseline data may be helpful when interpreting current
AO-7 Telemetry.
Spacecraft: AMSAT-OSCAR 7
Contents: 12 continuous frames of CW telemetry
Date: 27 April 1975 (about 5 months after launch)
Orbit: 2041
Data submitted by: John Fox W0LER
Format (Frame numbers added for reference)
1A 1B 1C 1D
2A 2B 2C 2D
3A 3B 3C 3D
4A 4B 4C 4D
5A 5B 5C 5D
6A 6B 6C 6D
Frame 1
00 86 57 80
56 00 57 52
80 71 34 52
53 33 57 56
54 11 55 49
38 07 01 49
Frame 2
00 70 64 75
41 00 57 51
76 69 33 53
52 32 56 56
53 13 54 51
40 05 00 50
Frame 3
00 57 65 71
36 00 61 51
79 70 31 51
52 32 57 56
51 13 54 50
37 05 00 51
Frame 4
00 52 76 68
49 00 59 51
75 66 31 52
52 32 56 57
52 14 54 50
43 05 01 50
Frame 5
00 38 73 82
72 00 59 49
72 67 30 52
53 32 55 50
53 12 54 50
43 10 00 49
Frame 6
00 32 75 71
82 01 59 50
72 66 31 54
54 32 54 54
56 11 54 49
38 12 00 49
Frame 7
00 41 70 75
92 00 59 52
73 67 30 52
51 34 55 54
55 12 54 51
38 12 00 50
Frame 8
00 52 87 54
90 00 59 50
74 67 30 52
52 33 52 53
50 14 54 50
38 11 01 51
Frame 9
00 73 79 54
94 00 59 49
71 66 31 52
49 34 53 54
54 11 54 50
38 12 01 49
Frame 10
00 84 69 37
92 00 59 52
70 68 33 52
49 32 54 54
52 12 55 50
40 12 00 51
Frame 11
00 87 65 42
93 00 59 55
78 68 34 52
52 32 55 54
53 12 54 52
40 11 00 51
Frame 12
00 89 63 65
90 00 59 54
74 70 34 52
55 32 54 55
51 12 54 50
40 12 00 50
The above telemetry were provided by Martin Davidoff, K2UBC.
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Subject: AO-7 telemetry analysis
From: Mineo Wakita
To: amsat-bb
Date: Tue, 02 Jul 2002 21:03:16 +0900
I calculated and compared 2002's data with 1975's data of AO-7 telemetry
using with 'AO7tlmSS.xls' which is available at
http://www.amsat.org/amsat/ftpsoft.html#ss
http://www.amsat.org/amsat/ftp/software/spreadsheet/AO7tlmSS.zip
http://www.amsat.org/amsat/sats/n7hpr/ao7_tlm.html
AMSAT-OSCAR 7
Format:
1A 1B 1C 1D
2A 2B 2C 2D
3A 3B 3C 3D
4A 4B 4C 4D
5A 5B 5C 5D
6A 6B 6C 6D
The following frame numbers added for reference.
Frame1-4 were received on 27 Apr 1975.
Frame5-8 were received on 30 Jun 2002.
Date: 27 April 1975 Date: 30 Jun 2002 22:20:02 +0200
Provided: Martin Davidoff, K2UBC AOS : 19:39 UTC
Submitted: John Fox, W0LER Submitted: Jean-L. RAULT, F6AGR
About 5 months after launch 435,1 MHz beacon active (fast CW)
Orbit: 2041 Orbit: 26402
Frame1 Frame5
00 86 57 80 00 75 80 70
56 00 57 52 99 01 01 55
80 71 34 52 78 82 32 54
53 33 57 56 45 55 48 51
54 11 55 49 42 01 53 52
38 07 01 49 00 11 01 51
Frame2 Frame6
00 70 64 75 00 73 80 72
41 00 57 51 99 01 01 55
76 69 33 53 78 80 32 54
52 32 56 56 45 55 47 51
53 13 54 51 42 01 53 52
40 05 00 50 00 12 01 51
Frame3 Frame7
00 57 65 71 00 71 80 74
36 00 61 51 99 01 02 55
79 70 31 51 77 79 32 54
52 32 57 56 43 55 46 50
51 13 54 50 42 01 54 52
37 05 00 51 00 12 01 51
Frame4 Frame8
00 52 76 68 00 71 80 74
49 00 59 51 99 01 02 55
75 66 31 52 77 79 32 54
52 32 56 57 43 55 45 50
52 14 54 50 42 01 54 52
43 05 01 50 00 12 01 51
1A Total Array Current I = 29.5N ma
1B +X Quad. Array I I = 1970 - 20N ma
1C -X Quad. Array I I = 1970 - 20N ma
1D +Y Quad. Array I I = 1970 - 20N ma
2A -Y Quad. Array I I = 1970 - 20N ma
2B 70/2 Rptr RF Power Output P = 8(1 - 0.01N)^2 watts
2C 24 Timer Value t = 15.16N hours
2D Battery Charge/Discharge I I = 40(N - 50) ma
3A Battery Voltage V = 0.1N + 6.4 V
3B 1/2 Battery Voltage V = 0.10N V
3C Battery Ch.Regulator #1 Voltage V = 0.15N V
3D Battery Temperature T = 95.8 - 1.48N C
4A Baseplate Temp. T = 95.8 - 1.48N C
4B 2/10 Rptr PA Temp. T = 95.8 - 1.48N C
4C +X Quad. Array Temp. T = 95.8 - 1.48N C
4D +Z (S/C Top Plate) Temp. T = 95.8 - 1.48N C
5A 70/2 Rptr PA Temp. T = 95.8 - 1.48N C
5B 2/10 PA Emitter Current I = 11.67N ma
5C 70/2 Modulator Temp. T = 95.8 - 1.48N C
5D Inst. Swithing Regulator Input I I = 11 + 0.82N ma
6A 2/10 Rptr RF Power Output P = (N^2)/1.56 watts
6B 435MHz Beacon RF Power Out. P = 0.1(N^2) + 35 watts
6C 2304 MHz Beacon RF Pwr. Out. P = 0.041(N^2) watts
6D Midrange TLM Calibration Value V = 0.01N V
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
1A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ma
1B 250.00 570.00 830.00 930.00 470.00 510.00 550.00 550.00 ma
1C 830.00 690.00 670.00 450.00 370.00 370.00 370.00 370.00 ma
1D 370.00 470.00 550.00 610.00 570.00 530.00 490.00 490.00 ma
2A 850.00 1150.00 1250.00 990.00 -10.00 -10.00 -10.00 -10.00 ma
2B 8.00 8.00 8.00 8.00 7.84 7.84 7.84 7.84 w
2C 864.12 864.12 924.76 894.44 15.16 15.16 30.32 30.32 h
2D 80.00 40.00 40.00 40.00 200.00 200.00 200.00 200.00 ma
3A 14.40 14.00 14.30 13.90 14.20 14.20 14.10 14.10 V
3B 7.10 6.90 7.00 6.60 8.20 8.00 7.90 7.90 V
3C 5.10 4.954 4.65 4.65 4.80 4.80 4.80 4.80 V
3D 18.84 17.36 20.32 18.84 15.88 15.88 15.88 15.88 C
4A 17.36 18.84 18.84 18.84 29.20 29.20 32.16 32.16 C
4B 46.96 48.44 48.44 48.44 14.40 14.40 14.40 14.40 C
4C 11.44 12.92 11.44 12.92 24.76 26.24 27.72 29.20 C
4D 12.92 12.92 12.92 11.44 20.32 20.32 21.80 21.80 C
5A 15.88 17.36 20.32 18.84 33.64 33.64 33.64 33.64 C
5B 128.37 151.71 151.71 163.38 11.67 11.67 11.67 11.67 ma
5C 14.40 15.88 15.88 15.88 17.36 17.36 15.88 15.88 C
5D 51.18 52.82 52.00 52.00 53.64 53.64 53.64 53.64 ma
6A 925.64 1025.64 877.56 1185.26 0.00 0.00 0.00 0.00 w
6B 39.90 37.50 37.50 37.50 47.10 49.40 49.40 49.40 w
6C 0.04 0.00 0.00 0.04 0.04 0.04 0.04 0.04 w
6D 0.49 0.50 0.51 0.50 0.51 0.51 0.51 0.51 V
Panel Current:
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
1A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
1B 250.00 570.00 830.00 930.00 470.00 510.00 550.00 550.00
1C 830.00 690.00 670.00 450.00 370.00 370.00 370.00 370.00
1D 370.00 470.00 550.00 610.00 570.00 530.00 490.00 490.00
2A 850.00 1150.00 1250.00 990.00 -10.00 -10.00 -10.00 -10.00
Battery Voltage:
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
3A 14.40 14.00 14.30 13.90 14.20 14.20 14.10 14.10
3B 7.10 6.90 7.00 6.60 8.20 8.00 7.90 7.90
3C 5.10 4.95 4.65 4.65 4.80 4.80 4.80 4.80
6D 0.49 0.50 0.51 0.50 0.51 0.51 0.51 0.51
Temperature:
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
3D 18.84 17.36 20.32 18.84 15.88 15.88 15.88 15.88
4A 17.36 18.84 18.84 18.84 29.20 29.20 32.16 32.16
4B 46.96 48.44 48.44 48.44 14.40 14.40 14.40 14.40
4C 11.44 12.92 11.44 12.92 24.76 26.24 27.72 29.20
4D 12.92 12.92 12.92 11.44 20.32 20.32 21.80 21.80
5A 15.88 17.36 20.32 18.84 33.64 33.64 33.64 33.64
5C 14.40 15.88 15.88 15.88 17.36 17.36 15.88 15.88
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Subject: [amsat-bb:60287] OSCAR 7 Orbit Number, Add 100,000
From: "Armando Mercado"
To: amsat-bb
Date: Wed, 3 Jul 2002 05:23:33 -0400
Using NASA Element Set #97 as a reference:
OSCAR 7
1 07530U 74089B 02183.17214469 -.00000029 00000-0 10000-3 0 976
2 07530 101.7945 227.7509 0012028 163.1344 197.0130 12.53558813264195
At epoch 2002 183.17214469, Oscar 7 had a Mission Elapsed Time of
10090.45625 days. Launch was Nov. 15, 1974 at 17:11UTC.
NASA has orbit number of 26419.
10090.45625 days x 12.53558813 mean motion =
126489.8035 orbits - 100,000 = ~26490 orbits. In the ball park.
Using a mean motion of 12.52771648 (from "Getting to Know OSCAR
From the Ground Up" copyright 1977), you get
126410.375 orbits - 100,000 = ~26410 orbits. Almost in the infield.
I think this works out an average drag of ~0.000000062 rev/rev., which
seems reasonable.
So, it looks like the NASA orbit number is correct. Just add 100,000
for odometer flip.
CUL, Armando n8igj@amsat.org
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Subject: AO-7 CW beacon wave file
From: Mineo Wakita
To: jamsat-bb
Date: Thu, 04 Jul 2002 19:10:38 +0900
23 June 2002, 00:26-00:47UTC. 145.972MHz, 1720Kbytes:
http://www.ne.jp/asahi/hamradio/je9pel/20623a07.wav
04 July 2002, 00:45-01:06UTC, 435.107MHz, 1008Kbytes:
http://www.ne.jp/asahi/hamradio/je9pel/20704a07.wav
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Subject: AO-7 just 100000 on 22 Sep 1996
From: Mineo Wakita
To: amsat-bb
Date: Sat, 13 Jul 2002 07:27:02 +0900
The following is the updated kep 'orb02192.2l.amsat'.
AO-07
1 07530U 74089B 02191.71149483 -.00000029 00000-0 10000-3 0 990
2 07530 101.7958 236.2378 0011957 146.2756 213.9078 12.53558778265265
^^^^
I also calculated that the orbit number was 126526, not 26526.
126526 - 100000 = 26526 ... orbit numbers after 100000
26526/12.53558778 = 2116 ... these days (12.53558778 = mean motion)
2116/30 = 70.5 ... 70.5 months = 5 years and 10 months
Therefore I guessed that the time AO-7 passed just 100000 was about
September in 1996.
And I confirmed this exact time was Sep 22, 1996.
We know that orbit number changes from 99973 to 29 as below.
(264.55504505 is Sep 20, then 99973)
http://www.celestrak.com/NORAD/elements/
- Click 'Archives' in the bottom
- Click 'Special Data Request Form' in the bottom
- Input '07530' in the 'NORAD Catalog Numbers'
- Input 'Start Date' and 'Stop Date'
1 07530U 74089B 96260.48475394 -.00000031 00000-0 10000-3 0 6064
2 07530 102.0030 263.3017 0012229 251.9708 108.0031 12.53512155999227
^^^^
1 07530U 74089B 96264.55504505 -.00000031 00000-0 10000-3 0 6074
2 07530 102.0030 267.4157 0012225 242.6280 117.3547 12.53512083999736
^^^^
1 07530U 74089B 96269.02438360 -.00000031 00000-0 10000-3 0 6087
2 07530 102.0029 271.9329 0012216 234.7869 125.2058 12.53512204 294
^^^^
1 07530U 74089B 96273.49372225 -.00000031 00000-0 10000-3 0 6091
2 07530 102.0030 276.4498 0012219 225.3984 134.6089 12.53512303 850
^^^^
And I got the AO-7 kep of the element number 1 from NORAD web.
=====================================================================
07530 1974-089B OSCAR 7
Launched: 1974-11-15 (319) Start Date: 1974-11-15 (319)
v
1 07530U 74 89 B 74320.71941514 .00000000 00000-0 00000-0 0 15
2 07530 101.7318 5.4266 0003020 243.3410 116.7305 12.52803293 135
=====================================================================
N8IGJ / Armando Mercado wrote at 12:07:39 -0400, 15 Jul 2002:
Thank you Mineo for finding these elements of AO-7.
I loaded element set #607 for orbit 99973 in STSOrbit, and looked back
into time.
STSOrbit shows orbit #100,000 begining on:
22 September 1996 at 17:02:16 UTC crossing the equator at 12.19 East
Longitude.
(Mission Elapsed Time was then 7981 days, 23:51:16)
1996 was a leap year, 1 extra day.
73- Armando n8igj
Subject: UO-11 just 100000 on 31 Oct 2002
From: Mineo Wakita
To: amsat-bb
Date: Sun, 14 Jul 2002 18:22:51 +0900
I noticed that UO-11 might be passed over just 100000 of the orbit
number before long. UO-11 was launched on 2nd March 1984, and it's
now transmitting the beacon of 2m and 2.4GHz.
UO-11
1 14781U 84021B 02192.81508489 .00000954 00000-0 14297-3 0 8817
2 14781 98.0858 160.6605 0008946 197.2006 162.8901 14.76930622983497
^^^^
The above kep is 'orb02192.2l.asmat'. The orbit number is 98349,
so 1651 to 100000.
100000 - 98349 = 1651
1651/14.76930622 = 111.78588726
192.81508489 + 111.78588726 = 304.60097215
The epock time 304.60097215 is 14:25:24 UTC, 31 Oct 2002.
It maybe contains +/- one and a half hour's obserbational lag.
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Subject: AO-7 telemetry analysis #2
From: Mineo Wakita
To: amsat-bb
Date: Sun, 22 Jul 2002 +0900
The below telemetry data were received at 10:45-11:07UTC, 20 July 2002,
145.972 MHz by JH4DHX, Mr. Ohtani, and these all data were analized by
JE9PEL, Mineo Wakita, using with the following spreadsheet.
http://www.amsat.org/amsat/ftp/software/spreadsheet/AO7tlmSS.zip
http://www.amsat.org/amsat/sats/n7hpr/ao7_tlm.html
10:45-11:07UTC, 20 July 2002
All raw data
Frame1 Frame2 Frame3 Frame4
100 165 176 157 100 188 170 142 100 179 161 185 101 187 130 188
289 240 200 286 210 257 200 254 216 261 201 253 262 217 201 254
324 324 387 336 367 394 327 352 373 324 328 352 378 331 341 353
452 423 456 417 448 453 455 455 453 400 456 456 403 454 457 456
524 501 540 529 539 501 550 528 543 501 541 528 539 501 550 529
602 602 601 651 600 601 600 651 600 601 600 651 600 601 601 651
Frame5 Frame6 Frame7 Frame8
100 178 144 170 100 178 133 169 100 174 148 178 100 178 165 178
294 263 201 254 287 269 201 254 281 241 201 254 279 267 201 254
372 354 330 352 377 352 330 353 375 359 332 353 375 370 332 353
450 454 458 456 451 454 458 456 451 454 459 457 451 454 460 458
539 501 550 529 539 501 549 528 539 501 549 529 540 501 549 529
600 601 601 651 600 601 601 651 600 601 601 651 600 601 601 651
All analized data
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
1A 0 0 0 30 0 0 0 0 MA
1B 670 210 390 230 410 410 490 410 MA
1C 450 570 750 1370 1090 1310 1010 670 MA
1D 830 1130 270 210 570 590 410 410 MA
2A 190 1770 1650 730 90 230 350 390 MA
2B 2.88 1.48 1.22 5.51 1.1 0.77 2.78 0.87 W
2C 0 0 15 15 15 15 15 15 H
2D 1440 160 120 160 160 160 160 160 MA
3A 8.8 13.1 13.7 14.2 13.6 14.1 13.9 13.9 V
3B 2.4 9.4 2.4 3.1 5.4 5.2 5.9 7.0 V
3C 13.05 4.05 4.2 6.15 4.5 4.5 4.8 4.8 V
3D 42.5 18.8 18.8 17.4 18.8 17.4 17.4 17.4 C
4A 18.8 24.8 17.4 91.4 21.8 20.3 20.3 20.3 C
4B 61.8 17.4 95.8 15.9 15.9 15.9 15.9 15.9 C
4C 12.9 14.4 12.9 11.4 10.0 10.0 8.5 7.0 C
4D 70.6 14.4 12.9 12.9 12.9 12.9 11.4 10.0 C
5A 60.3 38.1 32.2 38.1 38.1 38.1 38.1 36.6 C
5B 11.7 11.7 11.7 11.7 11.7 11.7 11.7 11.7 MA
5C 36.6 21.8 35.1 21.8 21.8 23.3 23.3 23.3 C
5D 35.0 34.0 34.0 35.0 35.0 34.0 35.0 35.0 MA
6A 3 0 0 0 0 0 0 0 W
6B 35.0 35.0 35.0 35.0 35.0 35.0 35.0 35.0 W
6C 0 0 0 0 0 0 0 0 W
6D 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 V
Current
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
1A 0 0 0 30 0 0 0 0 MA
1B 670 210 390 230 410 410 490 410 MA
1C 450 570 750 1370 1090 1310 1010 670 MA
1D 830 1130 270 210 570 590 410 410 MA
2A 190 1770 1650 730 90 230 350 390 MA
2D 1440 160 120 160 160 160 160 160 MA
5B 11.7 11.7 11.7 11.7 11.7 11.7 11.7 11.7 MA
5D 35.0 34.0 34.0 35.0 35.0 34.0 35.0 35.0 MA
Voltage
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
3A 8.8 13.1 13.7 14.2 13.6 14.1 13.9 13.9 V
3B 2.4 9.4 2.4 3.1 5.4 5.2 5.9 7.0 V
3C 13.05 4.05 4.2 6.15 4.5 4.5 4.8 4.8 V
6D 0.51 0.51 0.51 0.51 0.51 0.51 0.51 0.51 V
Temperature
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
3D 42.5 18.8 18.8 17.4 18.8 17.4 17.4 17.4 C
4A 18.8 24.8 17.4 91.4 21.8 20.3 20.3 20.3 C
4B 61.8 17.4 95.8 15.9 15.9 15.9 15.9 15.9 C
4C 12.9 14.4 12.9 11.4 10.0 10.0 8.5 7.0 C
4D 70.6 14.4 12.9 12.9 12.9 12.9 11.4 10.0 C
5A 60.3 38.1 32.2 38.1 38.1 38.1 38.1 36.6 C
5C 36.6 21.8 35.1 21.8 21.8 23.3 23.3 23.3 C
Power
Frame1 Frame2 Frame3 Frame4 Frame5 Frame6 Frame7 Frame8
2B 2.88 1.48 1.22 5.51 1.1 0.77 2.78 0.87 W
6A 3 0 0 0 0 0 0 0 W
6B 35.0 35.0 35.0 35.0 35.0 35.0 35.0 35.0 W
6C 0 0 0 0 0 0 0 0 W
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Subject: AO-7 CW beacon
From: Mineo Wakita
To: amsat-bb
Date: Wed, 08 Oct 2003 10:50:37 +0900
AO-07, 145.972MHz, UTC 08:54 Oct.7 - 09:15 Oct.8, 2003
Anten. ZQ-81 (Qubical Quad, 8 ele)
Cf. http://www.ne.jp/asahi/hamradio/je9pel/ao7cwtlm.htm
UTC MHz Dop
23:54:00 145.9758 +4 AOS
55:00 145.9757 +4
56:00 145.9756 +4
57:00 145.9755 +4
58:00 145.9754 +3
59:00 145.9753 +3
00:00:00 145.9751 +3
01:00 145.9748 +3
02:00 145.9744 +2
03:00 145.9737 +2
04:00 145.9729 +1
05:00 145.9721 0 TCA
06:00 145.9711 -1
07:00 145.9705 -1
08:00 145.9703 -2
09:00 145.9701 -2
10:00 145.9700 -2
11:00 145.9700 -2
12:00 145.9699 -2
13:00 145.9699 -2
14:00 145.9698 -2
15:00 145.9698 -2 LOS
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Subject: AO-07 recorded
From: Mineo Wakita
Date: 2005 Sep 7, 20:08
I heard today AO-07 mode B with a broken CW carrier.
And I recorded it as a MP3 file.
http://www.ne.jp/asahi/hamradio/je9pel/50907a07.mp3
AO-07
Sep 7, 2005
10:23-10:45 UTC
19:23-19:45 JST
145.972 MHz CW
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Subject: AO-07 CW carrier FFT image
From: Mineo Wakita
Date: 2005 Nov 27, 10:28
Now AO-07 is sending only VERY weak CW continuous carrier.
I saved today it as a jpg image using by FFT program.
AO-07
Nov 26, 2005
23:33-23:55 UTC
Nov 27, 2005
08:33-08:55 JST
145.972 MHz
CW carrier
87 max elevation
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Subject: AO-07 CW telemetry
From: Mineo Wakita
Date: 2006 Jan 5, 21:07
I copied again AO-07 CW and saved them as a MP3 audio file.
The log were the same numerals on each channel.
One cycle was approximately 80 seconds.
AO-07
Jan 5, 2006
11:04-11:26 UTC
20:04-20:26 JST
145.972 MHz CW
54 max elevation
> HI HI
> 180 180 180 180
> 252 252 252 252
> 324 324 324 324
> 496 496 496 496
> 568 568 568 568
> 696 696 696 696
> HI HI
MP3, 403 Kbytes, 80 seconds:
http://www.ne.jp/asahi/hamradio/je9pel/60105a07.mp3
Cf.
http://www.emilyshouse.com/experthams/ao7/index.html
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Subject: [amsat-bb:95510] Re: AO-07 healthy CW
From: "Garie Halstead K8KFJ"
Date: 1:09, 15 Nov 2006
--- Mineo Wakita wrote:
> I heard today CW (145.972MHz) from AO-07.
> http://www.ne.jp/asahi/hamradio/je9pel/61114a07.wav
> 80 seconds
HI HI
180 180 180 180
252 252 252 252
324 324 324 324
496 496 496 496
568 568 568 568
696 696 696 696
HI HI
//Gary -K8KFJ-
Subject: [amsat-bb:95513] Re: AO-07 healthy CW
From: "Martin Gillen"
Date: 7:54, 15 Nov 2006
I plugged that data into the AO-7 telemetry calculator and got:
CH CHANNEL NAME Value
== ============ =====
1A Total Solar Array Cur 2360 ma.
1B +X Solar Panel Cur 370 ma.
1C -X Solar Panel Cur 370 ma.
1D +Y Solar Panel Cur 370 ma.
2A -Y Solar Panel Cur 930 ma.
2B RF Pwr. Out 70/2 1.8432 watts
2C 24 Hr. Clock Time 811.2 minutes
2D Batt Chg/Dischc Cur. 80 ma.
3A Battery Voltage 8.8 volts
3B Half-Batt Voltage 2.4 volts
3C Bat. Chg. Reg. #1 3.6 volts
3D Battery Temperature 60.28 C
4A Baseplate Temp. -46.28 C
4B PA Temp 2/10 Rptr -46.28 C
4C +X Facet Temp. -46.28 C
4D +Z Facet Temp. -46.28 C
5A PA Temp. 70/2 Rptr -4.84 C
5B PA Emit. Cur. 2/10 793.56 ma.
5C Modul. Temp. 70/2 -4.84 C
5D Instr. Sw. Reg. 66.76 ma.
Input Cur.
6A RF Pwr Out 2/10 5907.69230769231 mw.
6B RF Pwr Out 435 956.6 mw.
6C RF Pwr Out 2304 377.856 mw.
6D Midrange Telemetry 0.96 V Typ.(0.50 +- 0.01)
Calibration
Subject: [amsat-bb:95520] Re: AO-07 healthy CW
From: "Sil - ZL2CIA"
Date: 18:02, 15 Nov 2006
Firstly, thanks to Mineo Wakita (JE9PEL), Gary Halstead (K8KFJ) and
Martin Gillen (VA3SIE) for the reception, copying, and decoding the data
from AO-07.
I remember some of the discussion posted here, when AO-07 started
working again. The consensus seemed to be that the satellite had failed
25 years previously because too many of the NiCd cells in the battery
had become short circuited (as NiCd do with time). This had caused the
battery voltage to fall to a level too low to operate the transponder.
Time,(and perhaps corrosion caused by the battery chemicals) had
eventually created an open circuit and the satellite was now operating
directly from the solar panels. Certainly, it goes very dead once it is
in darkness which rather supports this idea.
However, channel 2D of the telemetry shows a Battery Charge/Discharge
current of 80 ma. Since this is positive, I assume that it represents a
"charge" current. I see too that the "half battery voltage" is 2.4
volts, while the full battery voltage is 8.8 volts. So the dead battery
is behaving like a 110 ohm resistive load and consuming 0.704 watts.
This doubtless explains why the battery is at a toasty 60 C and most of
the rest of the satellite is at -46 C.
Also freezing is the 10m PA (channel 4B). This is not surprising since
it was "off" when JE9PEL recorded the CW. Yet this PA is drawing almost
0.8 amps of emitter current and producing nearly 6 watts of RF. It's
consumming 7 watts (8.8V * 0.8A)making the PA about 86% efficient). Does
this mean that the telementry is unreliable (fair enough, it a very old
satellite)?
The 2m PA (channel 5A) is a whole bunch warmer at -5 C. This makes sense
since the 2m transmitter was the one sending the data (or perhaps it's
installed next to the battery!) I presume that the 2m beacon signal is
simply injected into the 2m PA. Is this correct?
The battery voltages (and half battery voltages) give some indication of
where the remaining short circuit cells might be (in case anybody wants
to go up and fix them - actually, I will do that if someone can give me
a lift). I wondered about this in a sort of hypothetical way. I'm
curious for its own sake (and clearly have too much time on my hands).
I tried to find some details of the satellites design via google, but
didn't (I'm sure others will succeed in this).
I also looked in my own humble Ham library for details of the design,
but didn't find any.
I guess that the satellite battery consisted of cells in series and
batteries in parallel, or perhaps of cells in parallel then in series to
make a battery. Does anybody know exactly? Can anybody point me in the
right direction?
Sil - ZL2CIA
Subject: [amsat-bb:95523] Re: AO-07 healthy CW
From: "i8cvs"
Date: 21:55, 15 Nov 2006
----- Original Message -----
From: "Sil - ZL2CIA"
Sent: Wednesday, November 15, 2006 9:01 AM
Subject: Re: AO-07 healthy CW
> Hi,
>
> I guess that the satellite battery consisted of cells in series and
> batteries in parallel, or perhaps of cells in parallel then in series to
> make a battery. Does anybody know exactly? Can anybody point me in the
> right direction?
>
> Sil - ZL2CIA
Hi Sil, ZL2CIA
Unfortunately Larry Kayser VA2LK the expert of the OSCAR-7 batteries
passed away 5 october 2004
I believe that actually the right people to supply you with the informations
about the batteries and BCR are Jan King W3GEY and Dick Daniels W4PUJ
However you can get many useful informations about the batteries of
OSCAR-7 reading a lot of letters from Larry Kayser wich are available in the
Amsat-BB Archives from june 2001
Best 73" de
i8CVS Domenico
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AO-7 70cm RTTY beacon
Mode D, 435.105MHz RTTY, 45baud, 85Hz shift
Received it by myself with set USB mode
10:00 UTC, 11 Mar 2009
Latest MM software: http://mmhamsoft.amateur-radio.ca/
Subject: [amsat-bb] Re: AO-7 70-cm RTTY beacon and telemetry on!
From: "Mike Rupprecht"
Date: Sun, 1 Mar 2009 16:19:30 +0100
Hi all,
this is a part of what I could decode this morning (08:53 UTC) over europe:
-00369-01918-02892-03693-04805-05040-06912-07.06-00000-09836
-10000-11770-12338-13714-14603-15937-16422-17398-10000-19148
-20484-21913-22902-23731-24775-25040-26888-27883-20000-29801
-30000-31000-32000-334.3-34000-35222-36247-37272-30000-39258
-40501-41915-42912-43767-44755-45041-46923-47.17-40000-49788
-50000-51767-92331-53009-54000-55000-56000-57000-50000-59852
-00530-05147-00530-05147-00530-05147-00530-05147-00530-05147
-00530-05147-00530-05147-00530-05147-00530-09147-00530-05147
-00368-01917-02891-03786-04708-05041-06911-0790.-00000-09739
-10000-11738-12299-13694-14603-15935-16400-17386-10000-1114V
-30000-31000-32000-33479-34000-35222-362h6-37280-38000-39257
73, Mike
DK3WN
-----Ursprungliche Nachricht-----
Von: amsat-bb-bounces@amsat.org
Auftrag von DeYoung James
Gesendet: Sonntag, 1. Marz 2009 16:09
An: amsat-bb
Cc: Jim DeYoung
Betreff: [amsat-bb] Re: AO-7 70-cm RTTY beacon and telemetry on!
Greetings,
I only recorded 1-minute of the RTTY from last evenings pass but was able to
decode channel 11 through 16 from it to augment David's (VK5DG) decodes.
Here is what I was able to decode using reverse,45,85 parameters. I also
used the 1974 AMSAT J. final parameters and equations conversions. Great job
to David for finding the 70-cm beacon on and decoding so much!
Ch Value Ok? Description Converted Value
-------------------------------------------------------
11 734 Y Battery volts 13.74v
12 326 N Half battery volts 3.41v
13 695 Y Regulated volts 23.63v
14 602 Y 10v Reg volts 9.38v
15 937 Y 9v reg volts 9.37v
16 422 Y Ch reg1 volts 6.53v
-------------------------------------------------------
Jim, N8OQ
Ref.
AO-7 RTTY Telemetry Decoder
http://www.dk3wn.info/files/ao7_rtty.zip
AO-7 Teletype Equations Conversions table
http://www.ka9q.net/AMSAT-Newsletter-1974.pdf
Historical AMSAT Newsletters
http://www.ka9q.net/newsletters.html
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