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Author Topic: NOAA-15 APT anomaly  (Read 4276 times)

Offline Pope Jim

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NOAA-15 APT anomaly
« on: December 07, 2013, 2309 UTC »
Seems like every time I'm receiving NOAA-15 lately, about halfway through the pass the visible sensor will change gain (or something), going from a normal image to either almost all black or almost all white.  The infrared image is unaffected, and NOAA-18 and NOAA-19 don't behave like this.  I assumed that something was broken on the satellite, but the POES status page doesn't say anything about it.  What's going on?
MF/HF: LF Engineering H-800 active antenna into SDRPlay RSP1 with HDSDR software
VHF/UHF: 2m/70cm groundplane antenna into R820T2/RTL2832U dongle with SDR# software
Ku: GeoSatPro 90cm dish on PowerTech DG-280 motor into Freesat V8 Super receiver

Offline n6spp

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Re: NOAA-15 APT anomaly
« Reply #1 on: December 10, 2013, 0521 UTC »
Pope Jim-

What is your 137mhz setup rcvr/ant/decoder etc?

thanks, Eric
(I use to run the poes-wx apt decoder here..but its been a year now)
Weak Signal and multi-modes, LF-VHF
 ~Alaska

Offline Pope Jim

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Re: NOAA-15 APT anomaly
« Reply #2 on: December 11, 2013, 0113 UTC »
Homemade QFH antenna, RTL dongle, SDR#, WXtoIMG.
MF/HF: LF Engineering H-800 active antenna into SDRPlay RSP1 with HDSDR software
VHF/UHF: 2m/70cm groundplane antenna into R820T2/RTL2832U dongle with SDR# software
Ku: GeoSatPro 90cm dish on PowerTech DG-280 motor into Freesat V8 Super receiver

Offline Pope Jim

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Re: NOAA-15 APT anomaly
« Reply #3 on: December 26, 2013, 1827 UTC »
After much searching (no thanks to Yahoo's USELESS new forum system), I found the answer on the WXSat mailing list.  Apparently, as the satellite crosses from day to night it switches the visual channel to a near-infrared channel. 
MF/HF: LF Engineering H-800 active antenna into SDRPlay RSP1 with HDSDR software
VHF/UHF: 2m/70cm groundplane antenna into R820T2/RTL2832U dongle with SDR# software
Ku: GeoSatPro 90cm dish on PowerTech DG-280 motor into Freesat V8 Super receiver