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Author Topic: Some adventures with Carrier Sleuth and thermal effects on SDR clock stability  (Read 1509 times)

Offline ChrisSmolinski

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Some adventures with Carrier Sleuth and thermal effects on SDR clock stability
« on: October 23, 2020, 1412 UTC »
Apparently I need to relocate the AFE822x SDR, right now it is near one of the HVAC air vents. You can see the systematic drift of carrier frequencies from an overnight recording, most likely due to temperature changes affecting the ADC clock frequency.

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Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 400 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree

Offline ChrisSmolinski

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Re: Some adventures with Carrier Sleuth and thermal effects on SDR clock stability
« Reply #1 on: October 23, 2020, 1414 UTC »
I moved the AFE822x SDR as far from the HVAC duct as I could, and ran a circa 24 hour recording again. Much better results!
You can see stations fade in and out around sunset and sunrise, and the overall noise level go up.

BTW, these extended waterfalls are generated with my Carrier Sleuth program for Windows and macOS, and work with SDR I/Q recording files from most popular SDR programs.
If you are a serious MW DXer, you need Carrier Sleuth  :)  Download a copy here https://www.blackcatsystems.com/software/medium_wave_carrier_display_app.html

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Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 900 ft Horz skyloop / 500 ft NE beverage / 250 ft V Beam / 58 ft T2FD / 120 ft T2FD / 400 ft south beverage / 43m, 20m, 10m  dipoles / Crossed Parallel Loop / Discone in a tree
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