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Crystal info needed...

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Hi all,
Does anyone have any info on how to "fake" a specific frequency crystal?
I need a 14.00000MHz rock and I can't afford to have one made. Prices on custom crystals have jumped over 4000% in just the last five years. So, is there a way to take some other frequency, do some circuit magic, and stuff it where it's needed? Thanks.
 
Why "fake" it?
Old PeeCee mainboards have salvageable assemblies.
14.318 MHz was a common frequency.

Mouser has HC-49/U AT-cut 30ppm rocks for US $0.40 -
much cheaper than they used to be.
And a CSA-309 type at 28 MHz at US $0.83 that could
be used with a /2.

The parts needed to construct a tuned oscillator, although
easily done, would cost more than a crystal, and be much
less stable and more temperature sensitive.

<als>
 
Yes, there are lots of alternatives, such as using a PLL locked to a higher (or lower) frequency crystal.

But a lot depends what you want the crystal for?, isn't 14MHz an amateur band? (or at least part of it).
 
But a lot depends what you want the crystal for?, isn't 14MHz an amateur band? (or at least part of it).

Hi,
Yes, I believe you are correct, but I'm not using it for that. I have a SW converter that outputs to an old AM radio. It has a 1.00000MHz offset, and since I already have 2.5, 5 and 10MHz time signals from WWV on it, I wanted to get 15MHz, too. I don't want to have to fool with it too much, so obviously, the best way would be a 14.00000MHz crystal. Any thoughts?
 
captainkirksdog said:
But a lot depends what you want the crystal for?, isn't 14MHz an amateur band? (or at least part of it).

Hi,
Yes, I believe you are correct, but I'm not using it for that. I have a SW converter that outputs to an old AM radio. It has a 1.00000MHz offset, and since I already have 2.5, 5 and 10MHz time signals from WWV on it, I wanted to get 15MHz, too. I don't want to have to fool with it too much, so obviously, the best way would be a 14.00000MHz crystal. Any thoughts?

In that case, how about a 14.318MHz crystal? - these are standard and freely available. It would move your converter output to a different frequency though.

If that isn't possible, use a PLL and lock a free running VCO to a different crystal frequency - say 1MHz, with divide by 14 from the VCO to the phase comparator.
 
A converter covering that range will almost
certainly include switch-selectable tuned
circuits for the particular band. Changing
the injection frequency will not be the only
modifications necessary. Find an old ARRL
Radio Amateur's Handbook; there used to
be (and probably still are) circuit examples
for WWV converters for 5/10/15/20 Mhz.
<als>
 
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