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From: Oliver Betz <ob...@despammed.com>
Newsgroups: sci.electronics.design,comp.arch.embedded
Subject: Re: 802.15.4 RF issues
Date: Mon, 29 Oct 2012 12:38:48 +0100
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"langw...@fonz.dk" wrote:

>> > my point is that for each different type of xtal you need to measure
>> > the resulting frequency and adjust the caps, it can be much more than
>> > 40ppm
>> > off
>>
>> Until i get the 2.5GHz frequency counter, i just have to keep trying
>> different crystals and caps.  I wonder if it's because of the ceramic
>> SMD vs. metal case HC-59 crystal, in terms of para. caps.
>
>you can just measure the xtal frequency

where "just measure" means using a high impedance (low capacitance)
probe or an output not connected to the crystal.

Oliver
-- 
Oliver Betz, Munich
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