Hi,
[Disclaimer: Not an electronics guy, but I've Googled enough to, I hope, ask the right questions.]
I'd like to have a very accurate, standalone (not-GPS/Radio-regulated) clock that I can use for celestial navigation. Accuracy matters a lot here, so I'm trying to get down to something in the 0.1 PPM range.
Not much exists on the market at any sort of reasonable price point, so I'm thinking I'll need to build what I'm after, and my current thinking is that something based on the Arduino platform will be the easiest path to success.
If I were happy with 10ish PPM, there are lots of packages out there that provide realtime clock capabilities that make things straightforward. You know: Turning the oscillations of a crystal into something meaningful like date and time. (EG: http://www.sparkfun.com/products/99)
But I'm looking for greater accuracy. It appears that an OCXO oscillator will give me the level of accuracy I need, but I'm not sure what I need to do to build the intelligence layer on top of the oscillator to translate to date and time.
Are there clock modules that can accept an OCXO as an input? The clock modules I've seen (EG: http://www.maxim-ic.com/datasheet/index.mvp/id/2688) do appear to support external _crystals_ but they all want 32.768kHz and I haven't seen an OCXO rated at that.
Any tips/pointers would be much appreciated!
Thanks,
-Ben
[Disclaimer: Not an electronics guy, but I've Googled enough to, I hope, ask the right questions.]
I'd like to have a very accurate, standalone (not-GPS/Radio-regulated) clock that I can use for celestial navigation. Accuracy matters a lot here, so I'm trying to get down to something in the 0.1 PPM range.
Not much exists on the market at any sort of reasonable price point, so I'm thinking I'll need to build what I'm after, and my current thinking is that something based on the Arduino platform will be the easiest path to success.
If I were happy with 10ish PPM, there are lots of packages out there that provide realtime clock capabilities that make things straightforward. You know: Turning the oscillations of a crystal into something meaningful like date and time. (EG: http://www.sparkfun.com/products/99)
But I'm looking for greater accuracy. It appears that an OCXO oscillator will give me the level of accuracy I need, but I'm not sure what I need to do to build the intelligence layer on top of the oscillator to translate to date and time.
Are there clock modules that can accept an OCXO as an input? The clock modules I've seen (EG: http://www.maxim-ic.com/datasheet/index.mvp/id/2688) do appear to support external _crystals_ but they all want 32.768kHz and I haven't seen an OCXO rated at that.
Any tips/pointers would be much appreciated!
Thanks,
-Ben