> On July 10, 2014 at 10:55 AM ewkeh...@aol.com wrote: > > > As part of the FE 405 B project a separate output circuit is in the works. > The universal controller and auxiliary board are the same as used in the > FE5680A GPSDO but because of the very low ADEV a separate circuit board that > divides by three and has also two ground isolated transformer outputs is in > the works.The question is what is the best sine to square wave converter > with the lowest ADEV contribution. I am looking at Bruce's circuit using the > ADCMP600. Any other ideas? > Thanks Bert Kehren > _______________________________________________ > 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.
Although CERN likes that circuit for its ruggedness and versatility its a little noisier than some alternative circuits. Currently Linear Technology's sine to square wave devices with selectable filtering (LTC6957 series) are better in that they are a closer approximation to the ideal zero crossing detector. Failing that the next best is perhaps an AC coupled (both at input and between emitters) differential pair of 2N3906's or similar. Bruce _______________________________________________ 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.
