Scott, It doesn't look like AT-cut. AT-cut oven crystals are run at their upper turnover point, which is a minimum, so the frequency starts high from power up at normal room temperature. With SC-cut, the f/T curve is shifted to the right and they are operated at their lower turnover point (a maximum), so the frequency starts off low.
Regards, Garry On 08/10/2014 08:54 AM, Scott Newell wrote: I'm curious if an OCXO has an SC or AT cut crystal in it. There's no EFC, so I can't measure sensitivity. I did measure the frequency change from cold startup, thinking that an SC cut would stabilize quicker than an AT. I don't have a good AT OCXO to compare against, but I do have a Morion MV89A (should be an SC, right?). Graphs: http://n5tnl.com/time/mv89a/mv89a.png http://n5tnl.com/time/mv89a/unknown.png _______________________________________________ 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.
