How to make, where to buy, order 5 kHz, 10 kHz, 15 kHz crystal/ ceramic resonators

On Wed, 15 Nov 2006 11:34:36 -0800, la-la Has Frothed:

Try a CD4060 -

Then you can use a sane crystal freq. ;-)

Or, you could look into "tuning fork crystals", which is the type of the

Good Luck! Rich

We have many tens of thousands of crystal oscillator modules in stock at fifty cents each.

Our lowest frequencies are 28.8 kHz, 108 kHz, 153.6 kHz, 250 kHz, 256 kHz, 307.2 kHz, 326.4 kHz plus hundreds of higher frequencies.

In general, it is usually cheaper and simpler to use a higher frequency and a CMOS binary divider.

Also in general, if your system does not use a crystal frequency of

Oops.

Should be 3.579545 of course.

On a sunny day (Wed, 15 Nov 2006 13:19:46 -0700) it happened Don Lancaster wrote in :

Poor guy ;-)

Don Lancaster wrote in news: snipped-for-privacy@mid.individual.net:

Where does 3.579545 MHz come from?

...

TV color burst.

Cheers! Rich

NTSC color burst.

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Michael A. Terrell Central Florida

So, if I need a 4 MHz clock for a CPU, I should scrap it and make it a lot more complex to use a color burst crystal? How about those 10- MHz frequency standards? Show me a SIMPLE design for a TCXO to proved a low distortion 10 MHz signal from a 3.5795454545 crystal. Yes, i know that it can be done, but why? There are dozens of common, off the shelf crystal frequencies that are dirt cheap.

TV color burst.

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The speed of sound in quartz is (depending on shear vs. compression wave)

At 15 kHz, an AT quartz resonator would need to be (in size) about 200 times that,

For wristwatches, a tuning-fork is used, and one can micromachine it from quartz and laser-trim its weighted tines for frequency and couple to it using the quartz material's piezoelectric properties. Those are mechanical oscillators with non-quartz parts, but they still get called 'quartz resonators'. The common frequencies are mass-produced, and that means 32.000 kHz and 32.768 are available, but not the lower frequencies you ask about.

The typical resonators used for 5 kHz are tuning forks and guitar strings, or they aren't mechanical at all...

Color burst frequence in NTSC signals...

Charlie

The colour subcarrier of NTSC-encoded colour television broadcasts. The crystals, being very common at least in the USA, are cheap. FWIW, the NTSC colour subcarrier is nominally at 63/176 times 10MHz (with a tolerance of +/-10Hz; usually kept much closer to the nominal than the tolerance would allow), the horizontal scan frequency is 2/455 times the colour subcarrier frequency, and the vertical scan frequency is

There are other "inexpensive" crystal frequencies. Low kHz frequencies, of course, are not among them, but accurate generation of low kHz frequencies is possible through division from higher crystal frequencies.

Cheers, Tom

Not all of us are trying to build TV Typewriters for $5 or less, Don. :-)

But if you can find me some way to get VHF and low UHF signals down to a 45MHz IF with 32kHz and colorburst crystals, I'd love to hear it!

More information on exactly why 3.579545MHz was chosen:

This guy came close , quartz ring, not a frisbee, but close :

Steve Roberts

But color burst crystals are free, if the neighbor tosses their TV. ;-)

Cheers! Rich

Ah, HA! At last! "The remaining vertical blanking interval lines are typically used for datacasting or ancillary data such as video editing timestamps (vertical interval timecodes or SMPTE timecodes on lines 12-14 [3] [4]), test data on lines 17-18, a network source code on line 20 and closed captioning, XDS and V-chip data on line 21. Early teletext applications also used vertical blanking interval lines 14-18 and 20, but teletext over NTSC was never widely adopted by viewers [5]."

Anyone for a commercial skipper? I think I might hack into my TeeVee, and sync up line 20 and see if there's any predictable change when they go to commercial. "Network source code"? Sounds fascinating!

I wonder where I'd look up the coding protocol?

Cheers! Rich