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From: kludge@grissom.larc.nasa.gov ( Scott Dorsey)
Newsgroups: sci.electronics,rec.radio.amateur.misc
Subject: Re: Adjust frequency of4 terminal, rectanglular oscillators?
Message-ID: <1991Apr22.135656.20511@news.larc.nasa.gov>
Date: 22 Apr 91 13:56:56 GMT
References: <1991Apr20.012710.266@ac.dal.ca> <1991Apr20.231230.5685@zoo.toronto.edu> <1991Apr20.235945.7393@zoo.toronto.edu>
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Reply-To: kludge@grissom.gatech.edu ( Scott Dorsey)
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In article <1991Apr20.235945.7393@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>I wrote:
>>> For space saving and cost reasons I would like to use one of 
>>> those small can oscillators with 4 terminals...
>>Very probably what you've got there is a crystal oscillator...
>
>My mistake; turns out there are other things that use the same package.

Nope, he's probably using a crystal oscillator as you said (or one with a
ceramic resonator).  What he should be using is a voltage-controlled
oscillator in a 4-pin can, like the ones that MuRata Erie make.  I do 
heartily recommend them.
--scott
   (or you can always open up the can and put a varactor diode across the
element, then adjust the bias of the varactor to slew it like a VCXO)