off the wall
#1 off the wall
here's one...
does anybody know if there is any effect in potting a crystal oscillator in epoxy?
does anybody know if there is any effect in potting a crystal oscillator in epoxy?
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#2 Re: off the wall
Can't think of any, except can't access any components if it goes wrong. (But applies equally to any potted)
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#3 Re: off the wall
Potting the oscillator should have no effect, assuming the epoxy is non-conductive.
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#4 Re: off the wall
Make sure you can get the wires out !
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#6 Re: off the wall
if you're asking me why I asked then..
It's something I have no experience of/with and I wanted to know if there were any issues associated.
but if you're asking about Mark's question then it looks like he's assumed I would be potting it before it was connected in circuit...and yes that would be a serious no no.
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#7 Re: off the wall
a. I'm assuming it has wires
b. It was a joke
b. It was a joke
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#8 Re: off the wall
It was more "what is your rationale for doing this"?
If the oscillator is running at RF frequencies then the change in dialectic constant surrounding it could well have an effect (depending on type of oscillator).
If the oscillator is running at RF frequencies then the change in dialectic constant surrounding it could well have an effect (depending on type of oscillator).
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#9 Re: off the wall
I'll take that as a yes then...
most confusing though. In post 3 you said no effect and in the last post you said yes, some effect.
I think I'll just pot it and be damned.
most confusing though. In post 3 you said no effect and in the last post you said yes, some effect.
I think I'll just pot it and be damned.
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#10 Re: off the wall
I would doubt it, most quartz crystals I have seen are in a tin can anyway. Plus I don't think their resonant frequency involves capacitive effects so not sure how the dielectric constant around them would alter anything.
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#11 Re: off the wall
I was very careful to state "depending on type of oscillator"... There are several types of possible design here...
Obviously most quartz crystal based oscillators should be ok, but if this is an RF design using air-cored inductors potting it could be problematic...
Obviously most quartz crystal based oscillators should be ok, but if this is an RF design using air-cored inductors potting it could be problematic...
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#12 Re: off the wall
Look at the first post.
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#13 Re: off the wall
Yep. "Crystal oscillator" - no specifics as to the DESIGN of said oscillator, other than it had a crystal somewhere.
i.e. more information is needed for a definitive answer.
i.e. more information is needed for a definitive answer.
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#14 Re: off the wall
Yes there are radio oscillators that use crystals for tight channel stability.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."