Tom For simple, cheap, low performance and fast to build with junk box parts, hard to beat: What I made long ago for myself (before time-nut days). I still use it today for low end stuff, and it is all done with standard 74HC DIP parts. The main IC is a 74HCT4046 Phase lock loop with internal Osc. The internal osc output is divided by 16 using a 74HC93. The 10MHz ref is divide by 10 using a 74HC90 The two 1 MHz signals are feed into it's phase comparator. A couple of resistors and caps and I have a low tech 16 / 8 / 4 / 2 / 1 MHz tracking ref. With a couple of tweaks, I got the noise jitter down to a couple of ns as measured with a scope. 16 MHz is pushing the limits of the internal Osc, but I did not have any trouble getting there using less than the recommended osc cap. ws ******************** "What's the simplest way to generate 16 MHz from 10 MHz? This will be for clocking a microcontroller at 16 MHz given 10 MHz (Cs/Rb/GPSDO). Low price and low parts count is a goal; jitter is not a concern but absolute long-term phase coherence is a must. The ICS525 (as in TAPR Clock-Block) is a good candidate but I was wondering if there's something cheaper, less functional, and maybe not SSOP. Any suggestions? Thanks, /tvb