WBAA went to 20k! No more,they offer HD crap. You could hear a mile away station weakly in the speaker at ear height front and center that was 30 kHz away from their frequency. Speakers on the ceiling are for Muzak only. It made the thing so much easier to show-and-tell that my son actually showed a little interest. I recently used a powered speaker on a crystal set instead of the high Z earphone. Great job Chris Love the rig you built up the sound quality is impressive. But a lot more people than you might suspect take crystal radio development pretty seriously. The filter is just a Litz coil and a capacitor, but it adds selectivity to the system. You can also rotate the antenna coil to affect the coupling. One novel feature of the bandpass filter is that to use it, you slide the coil between the antenna tuner coil and the detector coil. The radio has four subsystems: an antenna tuner, a bandpass filter, a detector, and a powered audio output system. With no amplifier, a strong signal input is crucial.
He recently posted a video see below of his high-performance crystal set.
When you think of a crystal radio, you probably think of something simple maybe built out of household scraps.
