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Author Topic: GPS discipline a cheap Ebay DDS module  (Read 1623 times)

Offline redhat

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GPS discipline a cheap Ebay DDS module
« on: September 23, 2017, 2107 UTC »
A neat idea I came across today.  Instead of disciplining the reference oscillator, just measure its drift and update the DDS frequency!  Generate any frequency from 10Hz-30MHz with precision of better than 1 Hz.

Uses (mostly) off the shelf hardware.  You do have to build a divide by 32 prescaler for the DDS clock.

PDF http://www.knology.net/~gmarcus/VFO/GPS_Sig_Gen_v1_1.pdf

Arduino code http://www.knology.net/~gmarcus/VFO/AD9850_gps_vfo_v1.ino

+-RH
« Last Edit: September 23, 2017, 2133 UTC by redhat »
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Offline ChrisSmolinski

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Re: GPS discipline a cheap Ebay DDS module
« Reply #1 on: September 23, 2017, 2131 UTC »
Interesting, thanks for sharing. I just (and mean just, it arrived today) got an Arduino to play with. So far I've read a membrane keypad and sent text to an LCD display. I've got a rotary encoder on the way, I understand knobs are retro and in fashion again.
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