Ham radio talk: Bending rocks

mikeofaustin

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Jan 24, 2008
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So I was doing some work today that had a crystal oscillator. The frequency was WAY off (26.025Mhz for a 26MHz crystal) . My first thought was, "No way in heck can a crystal be pulled that far off" (that's about a thousand ppm off for a 10 ppm crystal).

But, low and behold, the crystal didn't have stabilization caps, and was in fact way off. I put some 30 pico's down, and it was then about 3kHz lower than the spec'ed frequency.

I am now a believer of rock bending. I just didn't know you can pull them so far off frequency. Wow.

Now, if we could just find a use for that, instead of using something like a PLL or DDS. But I guess with Rock bending, the component requirements are a lot less.
 

If the frequency changes from 25kHz above to 3kHz below rated frequency by only adding 30pf, you have a bad crystal. It should vary that much no matter what you do.
 

Johnnysan said:
If the frequency changes from 25kHz above to 3kHz below rated frequency by only adding 30pf, you have a bad crystal. It should vary that much no matter what you do.

Yes, and I though so too. I thought that a 10ppm crystal shouldn't bend 'that much'. But to my surprise, we were debugging a 25KHz shift in an oscillator (actually a cell in a Texas Instruments asic). But sure as shoot it bent to about 25KHZ above with no loading caps...

We later tried various crystals and learned that loading caps will in fact, play a major impact on the freq. To low in puffs will give you a high freq, but too high in puffs will give you a lower freq.

Freaky aint it???? i never would have expected that crystals were so flimsy. You? (I mean, were talking about crystals here, not an RC oscillator).

Edit: We tried 3 different x-tals (different manufacturers). All of them exhibited the same freq shift.
 

this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
 

Hi Mike, Johnny: have you ever tried slightly regrinding the crystal or loading it with a tiny bit of solder, then working it up? also which axis of the crystal is being used?

Don Jose de La Mancha
 

steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
:laughing7:
 

steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
This thread isn't the only place with unintelligible posts:
http://forum.treasurenet.com/index.php/topic,278386.msg2000972.html#msg2000972
 

pigiron said:
steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
This thread isn't the only place with unintelligible posts:
http://forum.treasurenet.com/index.php/topic,278386.msg2000972.html#msg2000972
even you dont understand what i'm talking about.
 

steve71 said:
pigiron said:
steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
This thread isn't the only place with unintelligible posts:
http://forum.treasurenet.com/index.php/topic,278386.msg2000972.html#msg2000972
even you dont understand what i'm talking about.
There's a problem in the Timor sea that could benefit from your knowledge.
 

HI kiddies, what Mike, Johny, & Zepher are intelligently talking about is a common factor in radio and especially important in metal detectors. Simply frequency control via crystals...

Before the metal detectors adopted it, they would stray off freq. in a minute or less, even going from sunlight to shade would change it. You had to constantly retune.

Garrett was the first to produce crystal controlled metal detectors with his BFO's.

What did you come up with Mike?

Don Jose de La Mancha
 

piggy said:
steve71 said:
pigiron said:
steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
This thread isn't the only place with unintelligible posts:
http://forum.treasurenet.com/index.php/topic,278386.msg2000972.html#msg2000972
even you dont understand what i'm talking about.
There's a problem in the Timor sea that could benefit from your knowledge.
10 blondes in a freezer called frosted flakes
 

Real de Tayopa said:
Old Chinese proverb "he who doesn't uderstand a post should be careful of putting foot in mouth"!

Don Jose de La Mancha
old white man saying,if your aunt had balls she'd be your uncle,lol
 

steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
The bad part is I know the business that you are in and the work that you do...How's business? Need any untrained flowback techs?
 

Inorganic oil is a muslim invention to make the West think that peak oil is a fantasy.
It has not worked and so the West seeks alternative energy sources for its transport
needs.
This is proof that Obama is not a Muslim.
 

Real de Tayopa said:
HI kiddies, what Mike, Johny, & Zepher are intelligently talking about is a common factor in radio and especially important in metal detectors. Simply frequency control via crystals...

Before the metal detectors adopted it, they would stray off freq. in a minute or less, even going from sunlight to shade would change it. You had to constantly retune.

Garrett was the first to produce crystal controlled metal detectors with his BFO's.

What did you come up with Mike?

Don Jose de La Mancha

We'll the original crystal in the BOM spec'ed 7pF. But we ended up around 17pF (must have been low parasitics in the ASIC). NOW, if I can just think of a use for this. I'm still in awe.
 

oldgoat said:
steve71 said:
this gas keeps rising so we have to raise the mud weight to keep it down.my lag strokes are 3500 and down strokes are 1245 so i know when and where the gas is comming from.i have 700'foot of bha 1200'of open hole we are at 13150'.we just POOH ELOG LD/DP ect.in other words i have no idea what your talking about,lol.you might understand alittle what i said.
The bad part is I know the business that you are in and the work that you do...How's business? Need any untrained flowback techs?
to dang slow i had to take a pay cut to go back to work
 

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