<div id="AOLMsgPart_2_f94d06d3-7bcb-464b-aed2-314f90761f0a"> <div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> Has anyone come across oscillators outputting the incorrect frequency when powered up. The frequency that is outputted reads 10.8 Mhz, and falls a few HZ as the ocxo warms up. The frequency is stable, even when measured over the course of many hours. It is a repeatable issue, when the ocxo's are powered from 2 particular power supplies. Yet when powered on again, they give the correct frequency. The affected ocxo's are c-mac units, both nos/"ebay" used.</div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860">Thanks, </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860">Brendan</div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> Sent from AOL Mobile Mail </div> </div>

Hi What you have is an SC cut OCXO that has an incorrectly tuned trap circuit in it (or a defective crystal). Of the two I’d bet on the trap. It’s firing up on the wrong mode and staying there. It switches back and forth due to interaction between the limiter stage and the trap circuit. Ideally there should not be any interaction ….obviously not true in this case. Bob > On Jun 19, 2016, at 4:51 PM, Iwa2008 via time-nuts <time-nuts@febo.com> wrote: > > > <div id="AOLMsgPart_2_f94d06d3-7bcb-464b-aed2-314f90761f0a"> > > <div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> > </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> > Has anyone come across oscillators outputting the incorrect frequency when powered up. The frequency that is outputted reads 10.8 Mhz, and falls a few HZ as the ocxo warms up. The frequency is stable, even when measured over the course of many hours. It is a repeatable issue, when the ocxo's are powered from 2 particular power supplies. Yet when powered on again, they give the correct frequency. The affected ocxo's are c-mac units, both nos/"ebay" used.</div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> > </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860">Thanks, </div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860">Brendan</div><div id="AOLMsgPart_2_bea72c74-0991-404a-ad92-fdbd77734860"> > Sent from AOL Mobile Mail > </div> > > </div> > _______________________________________________ > 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.