Hi Dick, I think a very inexpensive and simple way to multiply the 10MHz to 100MHz is the following. It only uses three standard CMOS chips: Use a 100MHz VCXO to generate your output frequency. Digikey has one for $28: Digikey number 744-1213-ND. This part has about -160dBc/Hz noise floor, quite nice. For the simple control logic: Use an NXP 74LVC163 counter with preload to divide 100MHz by 5 to get 20MHz. Use a 74LVC74 to get a 10MHz reference out of this 20MHz, with 50% duty cycle. Feed this 10MHz, and your 10MHz reference signal into an Exor gate (74LVC86). This is the phase comparator. Low-Pass filter the output of the Exor gate with a low pass filter that has <1Hz bandwidth. Say 2.2K Ohms into 100uF Tantalum with 100nF cap in paralell, into another 2.2K Ohms/100uF Tantalum low pass filter. This signal drives the VCXO input. That's all folks. Should cost you less than $35 including shipping, and generate a very stable 100MHz signal. Jitter, very low Phase Noise, etc determined by the 100MHz VCXO. ADEV determined almost entirely by the 10MHz reference source. bye, Said In a message dated 4/29/2008 14:17:50 Pacific Daylight Time, [EMAIL PROTECTED] writes:
Run a 100 MHz oscillator in a divide by 10 PLL (Phase Locked Loop) configuration, compared to your 10 MHz standard? If the Motorola / Freescale MC145170 (-2) was still in production, that might be a good one to use. Maybe National LMK03002. **************Need a new ride? Check out the largest site for U.S. used car listings at AOL Autos. (http://autos.aol.com/used?NCID=aolcmp00300000002851) _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
