[time-nuts] GPSDO project

Brad Dye brad at braddye.com
Mon Jun 29 09:08:15 EDT 2009

Many thanks to all who responded to my request for help on this project.

The SDR-IQ (http://www.rfspace.com/SDR-IQ.html) already has a built-in  
66.6667 MHz osc, I just want to make it more stable and reasonably  
accurate, as I use it as a general coverage HF receiver with a one- 
Hertz read-out. There is a place for a surface-mount jack on the PC  
board -- so that an external osc can be used -- although this feature  
is not promoted by the manufacturer. This SDR does most of its own  
processing in hardware and doesn't rely on a computer sound card as  
much as some SDRs do.

There was one response, offering a kit to do what I need, but it  
requires more test equipment for tuning and calibration than what I  
have available. I am still looking for a simple, completed oscillator  
that will accept 10 MHz from a Thunderbolt GPS receiver and supply  
66.66666 MHz for my SDR as described here:


My background is in radio paging where we use GPS receivers to keep  
our 900 MHz transmitters on frequency for simulcast operation. I  
really appreciate the time everyone took to offer suggestions.


Brad Dye, K9IQY
Springfield, Illinois

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