Colpitts Xtal Osc / Class E Power

From 2007 Amateur Radio magazine, full article from the index in Week 3. The oscillator is a Xtal Colpitts, then two digital inverters driving a BUZ90A Mosfet in Class E (saturated and off). Note the Amplitude Modulation transformer which is only a 240:30 Volt power tranny, in series with the drain circuit of the BUZ90A.
The transmitter is designed for 1.8MHz (just above the AM broadcast band).
1.8MHz transmitter
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