Bruce, is there any text about the ring resonator which discusses the features in the interferogram? Also I'd be interested in the configuration of the electrodes.
My present interpretation is that the vibratory resonance stems from contra-rotating modes each propagating around the ring, and that the fringe pattern is complicated by the two surfaces being a little bit out of parallel and with a hint of roughly spherical curvature relative to each other (probably not deliberate). I used to do a good bit of holographic interferometry, mostly related to identifying resonances and vibratory modes of blades on jet turbine rotors, and it's hard to break the habit of trying to interpret interference patters. Dana On Sat, Feb 29, 2020 at 7:34 PM Bruce Griffiths <bruce.griffi...@xtra.co.nz> wrote: > Interferogram showing vibration nodes etc for quartz ring resonator > frequency standard attached. > > Bruce > > On 01 March 2020 at 14:27 Bob kb8tq <kb...@n1k.org> wrote: > > > > > > Hi > > > > It’s also the size of the 2.5 MHz 5th’s and similar parts made “way > back”. They went into glass packages > > the size of door knobs. Packaging / design / mounting / processing has > changed a lot since then. > > > > Bob > > > > > On Feb 29, 2020, at 7:41 PM, John Moran, Scawby Design < > j...@scawbydesign.co.uk> wrote: > > > > > > Wow, that provoked an interesting discussion! > > > > > > Thanks for all the information and references to further information - > it should keep me quiet for a while. > > > > > > Interestingly 50mm diameter was about the diameter of the crystals > used by the British Post Office in the early days for generating a master > oscillator. It wasn't ground into a plano-convex lens but as a ring and was > about 10mm thick. Like the old WW2 crystals the electrodes weren't plated > but just contact rings. I have no idea what frequency they were ... by the > time that I realised they were scrapping all this kit it was gone and I > only managed to salvage two GPO Type 36 master 1S pendulums from a dumpster! > > > > > > Thanks again for all the feedback. > > > > > > John > > > _______________________________________________ > > > time-nuts mailing list -- time-nuts@lists.febo.com > > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > > and follow the instructions there. > > > > > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions > there._______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
