Tuning HuskySat-1 telemetry signal
Last night I didn't have any success decoding HuskySat-1's telemetry even though the signal was very strong. Thought today I might try using SpecTran to help position the USB signal for decoding. What audio frequency should I use? Approx 200 Hz?
73, Ken, W7KKE
Hey Ken!
For 1k2 BPSK, the span is around 3000 Hz (USB). So, most decoders expect (or can be configured) to see the center of the audio output at 1500 Hz.
Sometimes you can improve SNR a bit by narrowing the bandwidth to cut off some at each end, but that doesn't change the center being around 1500 Hz.
Here's a screen shot that I included with a tweet that illustrates this:
https://pbs.twimg.com/media/EPqD68nXsAIXN4V?format=jpg&name=large
-Scott, K4KDR
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-----Original Message----- From: Ken Swaggart W7KKE via AMSAT-BB Sent: Saturday, February 01, 2020 3:04 PM To: AMSAT-BB Subject: [amsat-bb] Tuning HuskySat-1 telemetry signal
Last night I didn't have any success decoding HuskySat-1's telemetry even though the signal was very strong. Thought today I might try using SpecTran to help position the USB signal for decoding. What audio frequency should I use? Approx 200 Hz?
73, Ken, W7KKE
Hi Ken, I find AF audio out from rear MAIN EXT SP jack to be best with IC-9700. IQ is tough at best. Carrier at 1300-1500. I’m having to tune manually a good bit with current TLE. I find Dot Product is giving me better copy. Mark N8MH
On Sat, Feb 1, 2020 at 3:10 PM Ken Swaggart W7KKE via AMSAT-BB < amsat-bb@amsat.org> wrote:
Last night I didn't have any success decoding HuskySat-1's telemetry even though the signal was very strong. Thought today I might try using SpecTran to help position the USB signal for decoding. What audio frequency should I use? Approx 200 Hz?
73, Ken, W7KKE
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participants (3)
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k.swaggart＠charter.net -
Mark L. Hammond -
Scott