Observation 3789787: SECOR 4 (1315)

Regarding Observation 3789787

Figured it was showing up the SatNOGS rotation for a reason so I scheduled a couple of observations.

Signal present from my station 1675 (ground plane) but is it really from SECOR 4/EGRS 4 circa 1965???

It also showed up in my other station 2051 (QFH) for the same orbital pass:


Unfortunately those are terrestrial signals @satcolintel5. You can see that they appear to move (not a straight line) thus are not following our doppler corrections.

Given your location and the FCC frequency allocation table, I am suspecting some sort of aeronautical mobile beacon.

Hi, it’s ACARS system: 136.850: SITA North American Frequency…


Thank you both for the explanations. I will re-mark those as w/o [valid] signal.



These signals (horizontal hashes) from CACTUS-1 are not a straight line either … so I have been incorrectly marking them as valid. Arghhhh. Live and learn.