Wednesday, March 18, 2009

Space radio NR, ANL, and other updates

Here is an article I saw on the Flex reflector, which speaks about using SDR in space

one of the stalwarts on the reflector designs space radios for JPL. His radios do -157dBm MDS

Now that's what I call a radio!!

The band stunk this morning so nothing to report on that front.

Bob N4HY has migrated from his custom beta thread to the main beta thread on the SVN, the code he has been working on regarding the RX image rejection is automatically adapted to the best performance on the frequency you are operating in real time. He has also redone the Noise Reduction and Auto Notch. For the first time NR really does something. I have owned half a dozen radios that claimed NR and half a dozen external DSP filters that claim NR. Usually they just add a lot of beeps and boops to the noise. This one has no boops but there is a clear change in the amount of noise in the pass band. The ANF is great. I was listening to a S-3 SSB signal last night when a s9+10 carrier came on. The ANL took out the carrier, then another S9 carrier came on a couple hundred hz higher and both were eliminated. In the mean time the AGC was left unaffected since the ANL comes before the AGC loop in Bob's scheme. Slicker n blobs of mucopolysaccharides (aka snot)!!

TX adaptation is soon to follow