Author Archives: trango

AERO-I 600 Baud GMSK

Currently there are 9 AERO-I 600 Baud GMSK channels on POR. Quite a bit of ACARS and CPDLC traffic along with the usual Call Management signaling units. These signals are huge as you can see from the “tightness” of the … Continue reading

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Aero Crypto Calls

Finally found an Aero H/H+ call that was encrypted. Supported crypto services on Aero are US-STU-III (Secure Telephone Unit), STE (Secure Terminal Equipment), FNBDT (Future Narrow Band Digital Terminal). Not clear which service this actually is but I suspect it’s … Continue reading

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Fleet Tracking on Inmarsat 4F3

Most of the popular Inmarsat activity is associated with ships and planes in AOR-E, AOR-W, POR and IOR. There is an Inmarsat satellite called 4F3 parked at 98W that gives CONUS coverage. This satellite is inclined and so does move … Continue reading

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Control Software for AOR AR2300

The AOR AR2300 is a PC Controlled All-Mode Communications Receiver that spans 40kHz to 3.15GHz. Since the radio is simply a black box with no front panel one must either use the software that comes with it or roll your … Continue reading

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SP5T Microwave Switch

Too many signals on different bands and tired of manually changing feed lines? Mini-circuits has a nice line of RF Matrix Switches that are USB controlled. I recently acquired a USB-4SPDR-A18 and have now finally gotten around to mounting and … Continue reading

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New Inmarsat Aero-H and H+ Decoder in Development

Another new decoder project is in the works. This is another Multi-Channel decoder for Aero but instead of just ACARS and CPDLC it does AMBE and LPC voice decode. The screenshot below shows call logging status output from the prototype … Continue reading

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ISEE-3 Frequency Drift Measured

Based on the latest Horizons update by JPL (based on Arecibo observations) I have measured the frequency drift of the spacecraft TX frequency (transponder A RHCP). It appears to be drifting upward at a rate of 3.3 Hz per hour. … Continue reading

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JPL Updates ISEE3 Horizon Data

Updated my Horizons data for ISEE-3 today and found this nice note: UPDATE (2014-Jun-23): Trajectory updated to JPL solution #32 (s32), based on 42 coarse Arecibo plane-of-sky angular measurements spanning May 22 – Jun 23 … Upon updating things and … Continue reading

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ISEE-3 Signal Getting Stronger

Each day the signal from the old but reliable ISEE-3 spacecraft gets stronger and stronger. I have updated the tracking software to log the signal strength over time. It’s also very easy to see the signal without averaging as shown … Continue reading

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Antenna Tracking Software Updated

I developed this little application a couple years ago to manage shuttle passes for automated s-band reception/recording. I have started using it more for DSN now and so have updated it with some new features. The tracker gets it’s Ephemeris … Continue reading

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