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trk results uo11 and ao40 Re: AO-40 S-Band Test



 >
 > Tried some more experiments with the S2 beacon on AO-40 today with mixed
 > results.  Pass was not nearly as good as last Sunday.  I acquired the
Almost undetected at sqint>115 here 1/13; then not too bad when looping back
to perigee. Seems
to be a high squint angle around the back with a slight whisper of a signal
on it, then when it gets
closer there's almost enough to do garbled data. A wrong setting prevented
recording.
AO40 was Pretty good at squint > 50 on 1/14/2001. Tried feeding the telem
server that Ron Parise set up,
did anyone see text come through that? 128.183.143.104 port 2121.
I have yet to catch it at a very good squint like Dave Guimont did this
morning.

Question 1 for the group:   How is 2line set number calculated.
Question 2 What is the insulator Made of on the 2m omni antenna, ao40
Question 3 Are VHF UHF transmitters pressurized and hermetic?
Question 4 Are the antenna elements insulated with a dielectric material,
paint, teflon, ceramic?
The implication here is that arcing or corona occured in the antenna
insulator, connectors or transmitters,
a slight amount of gas would make it worse such as when burning the engine,
and at this higher
power level something melted or burned open.

Using AO40 set24 the doppler curve didnt match the satellite very well at
the end of the 1/13/pass over USA
since I started using doppler freq to control the radio I could find the
satellite more often. At very high squints
off the back s beacon could be heard a few times thru the pass but was
impossible a few times too.
As it comes down close <15000 km it can be heard most of the time but the
doppler really walks a few
khz per minute.

rotation timing from audio recordings
0103001645z 17.7672rpm
0114011658z 17.7672rpm
timedate s(noise) sAO40min/max/comment
0114000930cst s3.1 s5-s9pk 10%garble no crc valid
0114001019cst s3.1 s7 pk squint 60 tlm 30%garble no crc valid rng
0114001117cst s2.9 s3.2-s5.0 squint70 tlm syncs rng 80%garble 44142 starting
to get too noisy
file t010114.raw 49blks
0114001132cst s2.5 s3.3-s4.5 squint71 tlm sync each 2 minutes afc bandwidth
set to .5hz

webpage updated:
http://members.home.com/nn0v/ao40report.htm

wav files
http://members.home.com/nn0v/40-011400165223.wav ao40 file time zulu 8 mins
uo11 switching between ssb and nbfm after it aquires then try to track the
doppler
http://members.home.com/nn0v/uo11az90el20_0113001930N42W91.4.wav
can hear the internal electrical signals modulating the s band slightly on
nbfm carrier...
The SETI League, Inc.   Link Analysis
User specifies variables shown in  Bold

Transmitter:
Frequency  = 2401.5 MHz;   l  =   12.5 cm
Transmit Power  = 5.8E-05 W   = -42.4 dBW  =   -12.4 dBm
Eff. antenna diam.  = 0.06 meters   = 0   ft
Illum. Efficiency  = 85 %
  Computed Antenna Gain = 1.9E+00 Ap  = 2.9 dBi
  Antenna Half Power Beamwidth = 2.1E+00 radian  =   1.2E+02 degrees
pretty weak number here>>>>>>>>>>> Effective Isotropic Radiated Pwr  =
1.1E-04 W  =   -9.5 dBm

Path:
Range  = 5.10E-11 parsecs = 1.6626E-10 LY  =   1.6E+06 m
  Free Space Isotropic Path Loss  =   164.0 dB
  Incident Isotropic Power =  EIRP -  path loss  =  -173.5 dBm

Receiver:
Eff. antenna diam.  = 2.76 meters   = 9.0551 ft
Illum. Efficiency  = 75 %
  Computed Antenna Gain = 3.6E+03 Ap  = 35.6 dBi
  Antenna Half Power Beamwidth = 4.7E-02 radian  =   2.7E+00 degrees
  Drift Scan time (zero declination) = 1.1E+01 min  =   640.4 sec
  Recovered Power =   P inc + G ant  =   -137.9 dBm
  System Noise Temperature = 50 K   =   -7.6 dB/To
  Detector Noise Bandwidth = 164 Hz  =   22.1 dB/Hz      << post process
spectrum fft size bandwidth
  Receiver Noise Threshold  =   kTB  = 1.1316E-19 J/S  =   -159.5 dBm
  Integration Time = 2.50E-04 sec  =   -6.9 dB/cy

SIGNAL TO NOISE RATIO     14.6 dB         < measured from the audio file





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