Chuck wrote: > i am going to be messing around with the garmin gps18-lvs for use with ntpd. > > i wish to modify the wiring instructions given here: > > http://time.qnan.org/ > > > i will eliminate the circuit board and leds instead opting for an inline fuse > holder and wiring the gps/serial/usb together in properly strain-relieved > inline wiring. > > now we get to my question. > > if i use an additional wire to extend the pulse, ground and power for no more > than 3ft in length, to power the 2 leds in their own box that can be attached > to the front of the computer to make the leds more easily visible, would this > extra length of wire create any kind of stub that would change the leading > edge pulse slew rate enough to cause it to become less accurate? or need i > only concern myself with such a thing in much higher frequencies? > > also, while i am asking dumb questions, do you think adding rj45 sockets > inline to allow using a standard ethernet cable to lengthen the wire from the > gps18 to the usb/serial junction would cause any problems? i would not > consider extensions of more than 6-9 feet. > > FYI I've got 30 feet of wire on mine and it's still working fine - the difference between the PPS fro the 18LVC and from my truetime box even with the added cable/slew issue is still less than the interrupt latency on my machine.
John _______________________________________________ timekeepers mailing list [email protected] https://fortytwo.ch/mailman/cgi-bin/listinfo/timekeepers
