The Well Tempered Master Clock - Building a low phase noise/jitter crystal oscillator

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I am looking at the options for upgrading the clock in my Marantz CD63. One thing I am also thinking about is using a twisted pair of wires from a Cat5 network cable.

Something I have also thought is that if you were to copy a CD on a PC/laptop the data on the copied disc would be experiencing the inaccuracies of the clock in the PC/laptop. Would I be right ?
 
Hi Andrea,

I'm looking at the TWTMC-D board manual, it seems C8, C9 and R11 are missing in the BOM.

Determined by the pictures should C8 and C9 being 0805 100nf X7R MLCC and R11 being 3223W 50K pot?

You are right, they are missing parts in the BOM.

C8 and C9 are 100 nF 100V X7R Mouser part 581-08051C104K4
R11 is 50k or 100k trimmer Mouser part 652-3223W-1-104
 
TWTMC-OVN

Little note about required 3/8" air conditioning copper tube. I recently discovered that it exists in two versions. With 1mm and 0.8mm copper wall thicknesses. You'll need the thinner one. Don't even loose your time with the other.
And anyway prepare your file. You'll have to reduce external dimensions of the pressed tube section in order to be able to fit it into pcb. Just enough to hardly insert it: this will much simplify soldering stage.

Have fun and great listenings with this project! And a BIG thank you to Andrea for all his efforts.
 
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Updated schematics, PCBs, BOMs and Assembly guide

Attached the assembly guides of all the boards available. They contain the schematic of each board, the BOM to source the parts and the instructions to build each circuit.

TWTMC-D assembly guide was updated adding the component values for 90/98 MHz SC-cut crystals.

- TWTMC-C: Colpitts-Clapp oscillator revised
- TWTMC-D: Driscoll oscillator revised
- TWTMC-P: Pierce oscillator
- TWTMC-AIO: Dual Driscoll oscillator with power supply
- TWTMC-D&D: daughter board (power supply, dividers, and so on) revised to supply the Driscoll oscillator and the oven board
- TWTMC-OVN: oven board for SC-Cut crystals Driscoll oscillator
- TWTMC-DIL: DIL adapter for Ian's Fifo board
 

Attachments

  • TWTMC-C.pdf
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  • TWTMC-D.pdf
    818.2 KB · Views: 212
  • TWTMC-P.pdf
    700.9 KB · Views: 136
  • TWTMC-AIO.pdf
    661.2 KB · Views: 140
  • TWTMC-D&D.pdf
    663.3 KB · Views: 148
  • TWTMC-OVN.pdf
    752.3 KB · Views: 144
  • TWTMC-DIL.pdf
    452.7 KB · Views: 145

TNT

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Attached the assembly guides of all the boards available. They contain the schematic of each board, the BOM to source the parts and the instructions to build each circuit.

TWTMC-D assembly guide was updated adding the component values for 90/98 MHz SC-cut crystals.

- TWTMC-C: Colpitts-Clapp oscillator revised
- TWTMC-D: Driscoll oscillator revised
- TWTMC-P: Pierce oscillator
- TWTMC-AIO: Dual Driscoll oscillator with power supply
- TWTMC-D&D: daughter board (power supply, dividers, and so on) revised to supply the Driscoll oscillator and the oven board
- TWTMC-OVN: oven board for SC-Cut crystals Driscoll oscillator
- TWTMC-DIL: DIL adapter for Ian's Fifo board

Please - always post updates to first page - typically these are very hard to find once you need them - thanks!

//
 
Andrea!
I start to assembly the Driscoll boards.
I did the first steps, I soldered the parts what the manual say for first, and I adjusted the half voltage, 3V on board C3 pins.
So the 45Mhz xtal board looks good, I measured 45.157 Mhz.
But the 49Mhz board was 53.569 Mhz, I dont know whats the problem, something with parts value, or soldering contact fault? I was very careful to sold the right value to the right place.
 
Andrea!
I start to assembly the Driscoll boards.
I did the first steps, I soldered the parts what the manual say for first, and I adjusted the half voltage, 3V on board C3 pins.
So the 45Mhz xtal board looks good, I measured 45.157 Mhz.
But the 49Mhz board was 53.569 Mhz, I dont know whats the problem, something with parts value, or soldering contact fault? I was very careful to sold the right value to the right place.

Seems that the crystal is running at B-mode instead of C-mode.
Have you installed the oven or are you testing the oscillator at environment temp?
 
You could try heating the Crystal at around 80°.
Please, try and let us know.
I heated it up but nothing changed.
But, when I start the board it goes on 53Mhz, if I touched the hot soldering iron to the base of the BFR182 it jumps to the exact frequency, 49.152 Mhz. It remains this good frequency long time, if I dont touch it. If I touch several at the soldered parts of board or I restart (supply off-on), it starts 53Mhz again.:confused:
 
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