Hi You want to mount the crystal at a point that is not moving (much) while the crystal is in resonance. For a normal AT, that's out at the edge. For most bar cuts, yes you mount it at a node. Without knowing the mode that the bar is resonating in, it's a bit hard to guess where the nodes will be. Just looking at the bar, you wouldn't *guess* that the end points would be nodes...
Bob On Jan 23, 2013, at 5:07 AM, Fabio Eboli <fabi...@quipo.it> wrote: >> Hi >> >> As with the one kg resonator, you need to mount the bar *somehow*. >> The idea is generally to suspend the resonator at a point that >> least affects the resonance (a dead spot). With a large bar, making >> it manually adjustable is practical. Not so much with a smaller part. >> >> Bob > > Il 2013-01-23 01:54 jmfranke ha scritto: >> I also have two of the crystals. The discs are used to adjust the >> phase of the acoustic feedback to the resonator ends. >> >> John WA4WDL > > Thanks Bob and John, I gave a superficial read to one of the patents, > as I understand the patent says that the plates are there to give > predictable acoustic reflections (yes I know I should read before posting > questions :) ) > Bob the dead spot mounting is interesting (are they called nodal points, > or I'm mistaking terminology?). > The metallization on the 50kc rod is on top and bottom plates, while > the 100kc is "swapped", one electrode on top on one half and bottom > on the other half rod. The suspension is also different, the > 50kc is supended in the middle while the 100kc is suspended > in two points. How are supposed to vibrate these bars? Will they inflect > along the long axis? Or elongate? Or a mix of different motions? > > Thanks. > Fabio. > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
