On Sat, 3 Mar 2012, Chris Albertson wrote: > On Fri, Mar 2, 2012 at 4:03 PM, Michael Deutschmann > > (Not my dream though. If I was to go to the trouble of installing a box > > outside my home and routing a cable through the wall to my computers, > > I'd like some weather sensors in the deal as well as just time...) > > No point in that because the weather data can be sent wirelessly from > outdoors. I tried to route wires and very quickly found it was > easier to place the NTP server near the GPS and use a two foot cable. > The whole setup is on a top shelf of an interior closet
In my fantasy device, the weather is logged by a daemon running on the same computer as NTPD. So the extra features would have no effect on the cable length. I don't like consuming spectrum if I don't need to. And even with wireless, sensors need power. Although that brings up one other idea -- a wireless GPS clock. That would be basically a relay that listens for long-range-line-of-sight signals, and then synthesizes a short-range-building-piercing signal for its owner to use. Only a simple pulse modulated signal would be needed -- the seconds could be labeled with NTP over 802-whatever wireless. * Back to ESR's plans, reading the comments I think he may actually not be adventurous enough. He estimates the budget of the volunteers who will run his sensors at under $200 and absolutely zero hardware work -- not even building an enclosure for a bare circuit board. Of that budget, $100 is taken by a linux router that will run his surveying software. So he figures a $75 maximum price for his GPS fob. (He could easily make this if not for the PPS problem.) It might make more sense to ask the hardware designers to invent a linux router and timing-grade GPS *in one box*, making the entire budget available to the custom part. Also, the USB conversion overhead would be gone -- you could even weld the PPS signal to a dedicated IRQ. Such a box would be just as popular with NTP hobbyists outside ESR's project as a USB fob. The sort of NTP hobbyist who rejects "router" boxes in favor of a customized old desktop will be holding out for RS-232 anyway. ---- Michael Deutschmann <mich...@talamasca.ocis.net> _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
