Why use a board full of TTL when an $1 8-pin chip will do it ?
On Thu, Jan 14, 2016 at 11:44 PM, Morris Odell <vilgo...@bigpond.net.au> wrote: > Am I missing something here? > > I understand the ease and fun of programming up an AVR as much as anyone > but surely this task could be accomplished easily with a chain of fast > synchronous TTL or CMOS dividers. A resynchronising FF could also be added > at the end to clean up the 1 pps if required. You wouldn't need to worry > about the maths or OBOBs either. > > Admittedly you would need more PCB real estate but that shouldn't be a big > deal in most cases. > > Morris > > > >>> If anyone is interested in the equivalent functionality using an >>> ATTiny25 (for instance, if you’re already heavily invested in AVR instead >>> of PIC, like I am), ping me. I’ve privately written code to solve almost >>> the same problem and it could easily be adapted into doing the same job. >>> >>> > >>>>> Is there an easy circuit to build that can consistently deliver a 1 >>>>> PPS from a 10MHz source with excellent resolution and repeatability? My >>>>> first application is to test different 10MHz oscillators without a TIC >>>>> always attached and then compare the PPS output change over time against a >>>>> master GPSDO PPS with an HP53132A. >>>>> >>>>> The circuit used for PPS generation would have to deliver consistent >>>>> PPS output with preferably not more than 100ps noise or jitter, assuming a >>>>> perfect source. I'm totally guessing that for this resolution, the PPS >>>>> would have to be generated and accurate to within 0.001Hz every second. >>>>> If >>>>> this is too difficult, maybe the integration time can be increased to >>>>> generate one pulse every 10second or every 100,000,000.00 cycles? >>>>> >>>> > > _______________________________________________ > 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. > _______________________________________________ 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.