On 2/13/2012 2:36 AM, Dave Hart wrote:
On Sun, Feb 12, 2012 at 19:03, Chuck Swiger<[email protected]> wrote:
On Feb 12, 2012, at 9:36 AM, unruh wrote:
The clock crystal ages, and suffers internal crystal "cracks"
migrations, etc, which change the frequency of the crystal. Thus even in
a temperature controlled oven, the crystal frequency will change, but
much of the crystal frequency change is driven by temperature changes.
Agreed, temperature swings will have a major impact on the crystal frequency.
Well, I know what you're saying but we're talking on the order of 1
PPM / degree C.
You might be able to improve the stability of the crystal by ensuring good
airflow and cooling via HVAC as needed. And I suppose you could adjust the
rate by changing the HVAC set-point, but I don't think the benefit is worth it.
I'd be more likely switch to an OXCO + GPS on a PCI/PCIe card if such as needed.
That's OCXO, oven controlled crystal oscillator. Why X for crystal?
Crystal is frequently abbreviated as XTAL. I think this usage may have
originated in amateur radio.
<snip>
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