[time-nuts] Re: Do crystals still jump?

[glenlist]

wow. Great story Detlef.

I have had crystals 'jump' but this was at the part per billion level... 
mainly hysteresis effects. It causes my pulling loop to go mad. There 
might have also been some non monotonic behaviour also.

I was told by the crystal mfr (this about about 30 yrs ago) the better 
crystals exhibited lower hysteresis, but it was present in all crystals 
to some degree. .


On 4/09/2022 6:26 am, dschuecker via time-nuts wrote:
> Hi,
>
> yes, they do jump.
>
> Some years ago our DSL-modems fell out of sync when they were exposed 
> to a temperature jump., ie. in the warm exhaust of a vac cleaner. 
> Sure, all xtals have a temperature dependency, but with this batch of 
> crystals there was a frequency change of 50ppm or so for a temp change 
> of 2Kelvin. These are perceived numbers, I do not have exact data. The 
> modems' PLL could not track the frequency change fast enough and the 
> modem fell outta sync. . We had a lot of these crystals in the field 
> and that was a pretty severe problem.
>
> Cheers
>
> Detlef
>