04-18-2013, 08:39 AM
Are you sure they are birdies? I've never actually heard those on an analog single reduction receiver. They're generally caused by spurious signals originating in a phase locked loop system. Much more common in analog receivers are images (and there generally are only two per frequency, 910 or whatever KHz apart. Can you describe what you are hearing? The bands are so cluttered with garbage signals from things like light dimmers, cable modems, etc., that it can be difficult to sort out the real stations from the garbage.
