[time-nuts] Mechanical 1PPS Oscillator Disciplining

Bob Camp kb8tq at n1k.org
Sat Jan 10 15:35:45 EST 2015


The mounting points are the standard locations for a flexure bar running the resonance along it’s length. The sandwich blank is a bit unique.

The normal gate feedback style circuits will get the crystal running. The impedance will be quite high, so you will need a bit of gain. At low frequencies, a CMOS input op-amp will do the trick. 


> On Jan 10, 2015, at 12:24 PM, David J Taylor <david-taylor at blueyonder.co.uk> wrote:
> Hi David yes I think I have seen similar but not as low as that. If you
> compare the suspension points the different vibrational mode should
> obvious.....the suspension point is at a node. I think some of these are
> quite difficult to excite, I have not seen any suggested circuits but I have
> not looked too hard.
> Alan
> ====================================
> I uploaded a couple of pictures taken with the 'phone.
> http://www.satsignal.eu/Radio/2015-01-10-1700-54-crop.jpg
> http://www.satsignal.eu/Radio/2015-01-10-1702-51-crop.jpg
> The first photo shows the size and mounting points of the crystal.  The crystal itself appears to be a two-layer structure.  The second photo shows a detail of one of the mounting points.  The gold plating appears to have been scraped away at the edge, and some sort of solder join made at the edge.  I might be able to do a better image with a different camera, but I don't know.
> Hope that is of some interest.
> David
> -- 
> SatSignal Software - Quality software written to your requirements
> Web: http://www.satsignal.eu
> Email: david-taylor at blueyonder.co.uk 
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.

More information about the time-nuts mailing list