On Wed, 14 Aug 2002 23:02:11 +0100, you wrote:

>On Wed, 14 Aug 2002 22:24:11 +0300, you wrote:
>
>>On Wed, 14 Aug 2002, Mike Singer wrote:
>>
>>>Harold M Hallikainen wrote:
>>>> Also, remember that setting a 12 MHz oscillator to
>>>> within 1 Hz means it isn't going to stay there.
>>>> That's 0.1 ppm. Really good crystal oscillators
>>>> (with temperature compensation or ovens) can maybe
>>>> do 1 ppm or so.
>>>
>>>Yes, from Electronicstalk.com:
>>>
>>>"The FTS501AH OCXO offers a frequency stability of
>>>+/-250ppb over the standard temperature range of 0 to 70C"
>>>
>>>(ppb =3D 1000 ppm ?)
>>
>>Yes, billion =3D 1e9
>>
>>The only small problem is price. Fox TCXOs were around $40 when I last
>>checked and the spec was worse than 0.25ppm.
>Almost every cellphone contains a TXCO, therefore they must be
>gettable for a lot less than $40.....


They are if you buy several million a month. Cellphone TCXO's also are
only good to about +/- 2.5 ppm, and then they sync to the inbound
channel to get closer than that.


Dave

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