Being plagued with extreme noise, ghosts, birdies, I fabricated a 4 pole Chebyshef bandpass filter.
The target CF was 150 Mhz, turned out more like 162 and 40 Mhz pass. the difference it made was mind blowing on my SmarT dongle, now I get those weak stations into usable. No more ghosts, no birdies. still has the usual spikes but stable and can discriminate really weak signals. Here is a before and after shot:
(said it before, these things need some filtering.)
The target CF was 150 Mhz, turned out more like 162 and 40 Mhz pass. the difference it made was mind blowing on my SmarT dongle, now I get those weak stations into usable. No more ghosts, no birdies. still has the usual spikes but stable and can discriminate really weak signals. Here is a before and after shot:
(said it before, these things need some filtering.)