On Tue, Jan 13, 2015 at 5:46 PM, Dr. David Kirkby (Kirkby Microwave Ltd) <drkir...@kirkbymicrowave.co.uk> wrote: > I had a brief read. Equation 1 made me wonder what could be achieved > with a cheap HeNe laser. It should be fairly easy to mix a couple of
See Sams Laser Faq section on stabalized HeNe Lasers: http://www.repairfaq.org/sam/laserchn.htm#chnsshnl1 This uses zeeman splitting to get two different polarization modes lasing at slightly different wavelengths. (this is described in more detail elsewhere in the FAQ about some commercial lasers that use this effect.) There are do it yourself at home grade (/ easily available surplus parts) things you can do to get the short term linewidth down to about 4MHz or so, sadly 4MHz out of 470THz is only 1e-8 or so, so not super competitive with some off the shelf OCXO. You're also then stuck with an optical standard, and the down conversion to microwave is decidedly more complex. It would probably be a fun time-nuts project, even given the not amazing performance, if not for the difficulty in down-converting to something that could feed a counter. _______________________________________________ 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.
