Adding a DDS isn't all plain sailing. ?
I got a horrible whine that was coupled into the BitX via the power supply rail. ?I needed to add some caps and big RF choke to provide isolation. That removed about 95% of it so it's hardly noticeable unless the antenna is removed. ?Another choke should fix it completely.?
Also I sometimes hear a lot of carriers from SW broadcast signals when tuning 7 MHz that weren't there when using the free running VFO. My theory is that it's a harmonic of the DDS VFO but I haven't tracked it down yet.?
