Hey everybody!
I had a very high pass of LilacSat-1 tonight and took the opportunity to try to see how I could improve the percentage of my transmissions that the satellite would digitize & repeat onto the downlink.
Wei from the project team at Harbin was kind enough to call to my attention that there should be a short delay ("a few hundred ms") before speaking so that the CTCSS decode could process. Following that period, the audio on the uplink would be passed on to the satellite's receiver.
As I tested various techniques while transmitting tonight, it became pretty obvious that I was getting MUCH better audio on the downlink with a full 2-second delay before speaking when I keyed the mic.
I was just wondering if anything like this had been seen on other satellites over the years. (or land-based systems, for that matter)
I realize that we're treading on new ground with this satellite processing the uplink audio with an on-board computer for transmission as a data stream on the downlink, but the front-end is still dealing with a standard FM carrier and PL, so I was curious if a longer-than-expected delay had possibly been seen elsewhere over the years.
Just trying to learn as I go. Thanks for any feedback.
Here's a sample of the quality of downlink I was seeing with that 2-second delay:
http://www.qsl.net/k4kdr/files/2017-06-07--0334--LilacSat-1--audio.mp3
-Scott, K4KDR