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The Well Tempered Master Clock - Group buy

I'm not sure what I need, could you help me please?

You need 2 oscillators, one at 22 MHz and the second at 24MHz. There are 3 types of oscillators: Clapp, Driscoll and Pierce, the Driscoll only works with SC-Cut crystals. Then you need the daughter board to supply the oscillator boards.

The problem is that a pair of Sc-Cut or AT-Cut crystals at 22/24 MHz is no longer available. There are in stock 22Mhz AT-cut and 24 MHz SC-cut.

So the only option is: 1 x TWTMC-D Driscoll oscilaltor board for the 22 MHz AT-cut Crystal, 1 X TWTMC_D oscillator board for the 24MHz SC-Cut Crystal, 1 x TWTMC-D&D daugther board to supply the oscillators (and obviously the 2 crystals above).
You could get bare boards or finished boards.
 
Best crystals you can get

I would suggest to keep in the right consideration a pair of crystals that could reach the best phase noise performance, since they have a Q around 2M.

These are SC-Cut crystals 3rd overtone from Laptech in cold welded HC-47/U package at 5.6448 MHz and 6.144 MHz:
ESR: around 125 ohm
C0: 3 pf
C1: 0.15fF
Q: around 2M

The MOQ is 15 pcs for each frequency.

If you don't need high sample rate this is the best option to get very low phase noise.
The discrete DAC I'm working on will operate the best with such low clock frequencies (5.6448 and 6.144 MHz).

Attached the new order form that includes the above crystals.
 

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You need 2 oscillators, one at 22 MHz and the second at 24MHz. There are 3 types of oscillators: Clapp, Driscoll and Pierce, the Driscoll only works with SC-Cut crystals. Then you need the daughter board to supply the oscillator boards.

The problem is that a pair of Sc-Cut or AT-Cut crystals at 22/24 MHz is no longer available. There are in stock 22Mhz AT-cut and 24 MHz SC-cut.

So the only option is: 1 x TWTMC-D Driscoll oscilaltor board for the 22 MHz AT-cut Crystal, 1 X TWTMC_D oscillator board for the 24MHz SC-Cut Crystal, 1 x TWTMC-D&D daugther board to supply the oscillators (and obviously the 2 crystals above).
You could get bare boards or finished boards.

Grazie / thank you Andrea.
 
I would suggest to keep in the right consideration a pair of crystals that could reach the best phase noise performance, since they have a Q around 2M.

These are SC-Cut crystals 3rd overtone from Laptech in cold welded HC-47/U package at 5.6448 MHz and 6.144 MHz:
ESR: around 125 ohm
C0: 3 pf
C1: 0.15fF
Q: around 2M

The MOQ is 15 pcs for each frequency.

If you don't need high sample rate this is the best option to get very low phase noise.
The discrete DAC I'm working on will operate the best with such low clock frequencies (5.6448 and 6.144 MHz).

Attached the new order form that includes the above crystals.


Andrea you have an idea what is the difference in phase noise levels between crystal at 5-6 MHz against 11-12 MHz against 22-24 MHz ect.....
 
- andrea mori can change my order from - SC-Cut 1 x 49.1520 MHz to 1 x SC-Cut 6.144 МГц

At the moment this is only an interest list, we have to meet the MOQ to place the order to Laptech: 15 pcs for each frequency (5/6 MHz).

So I can delete the 49MHz Sc-cut Crystal (in stock at Laptech) from your order, but I cannot guarantee you will get the 6.144 MHz until we will reach the MOQ.

Please, let me know.