[quote author="Freq Band"]Yes, 10MHz is the freq stated in my test equipment manuals as what's needed to calibrate....or use as an external reference.
...but you are right, how do I check this reference :? ?
(as in...which came first , chicken or egg?)
The seller "says" it has been checked already.
=FB=[/quote]
Right, chicken & egg :wink:
What's the complete module doing ? A complete oscillator, probably complete with oven ? Or just the Xtal & oven ? Obviously a simple CMOS-inverter and a few caps can make already a suited test-circuit, but will the seller do that for you ? So any idea how he has checked it ?
What's the price BTW ? If it's cheap then just buy & try to find someone nearby with a calibrated counter. There may be other tricks perhaps, like comparing with a simple but easily available frequency, dunno.
(FWIW: I recently plugged a gtr both into a Boss gtr-tuner and an HP-THD-test set and both were in very good agreement w.r.t. measured frequency... which tells me that while both units haven't been calibrated in years, it's unlikely that they're both really wrong, since then they had to be off in exactly the same manner, which is unlikely so most likely they're both pretty accurate... :thumb: )
So what's the accuracy you need ? Any reason to assume your lab-stuff is 'off' ? And if that's indeed the case, how bad is it that you've determined the range of an LFO a few % off ?
Bye,
Peter