Rubber grommit on CDP crystal


2005-01-27 8:22 pm
What happens to the sound with the blue tac / rubber grommet ?

Did you ground the case?

I will get a clock eventually (i have to figure out how to fit another PSU into the CDP) :xeye:

I understand from the forum that a low noise PSU is essential for a new clock!

Kind regards,

Less ragged more focussed sound....

I have grounded the case before on other crystals but did several other things at the same time too. Wrapped the crystal in lead tape (available from golf shops) then wrapped in amalgamating rubber tape and lay it flat on the pcb in a lump of blu tack with short thin (slightly looped) wires going to the PCB. The idea being to mechanically isolate the crystal from the PCB but also increase its innertia making it harder to mechanically resonate in the firtst place. It works well but I did all of this at the same time so can not say what made what difference...

Be careful grounding the can though, the heat from the solder job will probably affect the exact freq of the crystal. If you do want to do it grind at the can a little with a file or you will struggle to get the solder to bond to the can and you will need more detrimental heat...