One way would be to hetrodyne the DDS to higher frequency. And it is probably the best way. There are many microprocessor crystals and oscillators that can allow you to do this.
Bob Macklin K5MYJ Seattle, Wa. "Real Radios Glow In The Dark" ----- Original Message ----- From: Stephan Schaa To: [email protected] Sent: Sunday, January 24, 2010 10:04 AM Subject: AW: AW: AW: AW: [soft_radio] Re: LD-1 Discussion on Garage-shoppe.com Blog Thanks for your explanations, Bob! I understand the principles of driving the mixer with a squarewave signal and that you use a comparator to change sine to squarewave. Where I'm failing at is the trick how to receive 30 mhz with a DDS that make 37 MHz max without getting problems with nyquist. Can you use a comparator to double your VCO frequency without getting problems at the duty cycle? Stephan
