"David Lord" <[email protected]> wrote in message news:[email protected]... > David J Taylor wrote: > >> You'll have to get a GPS puck and wireless PC on the roof! Safely > > That looked a possibility earlier this year but treeline front > and back has shot up maybe a couple of metres already and if > same next year I'd be needing a mast.
Don't worry about trees - a modern GPS such as the GPS 18x LVC is very sensitive, and can work with a lot of obscuration. Although my GPS 18 LVC is sitting on the roof, the GPS 18x LVC works just as well sitting in a room on the top floor of the house. > I'm signed up in protest at various network over mains systems > due to them splattering and killing QRP reception. Me also. [] > I've not mastered the demodulation though and whilst on scope > it looks to be a clean and identifiable MSF timecode no > different than from Conrad module, a much closer look shows > noise spikes. I used an RC filter at output and suspect a > Schmitt as with Maplin circuit is needed. > > David What sort of filtering is used these days? I used to think a 60KHz crystal was required, with a bandwidth of a few 10's or 100's of Hz (there used to be a fast-code transmission on the signal). What's the rise-time required through the filter? 20ms fast enough? A Schmitt trigger would be worth trying, because although there will be some hysteresis on the PC input port, it will be more appropriate for RS-232 levels and not tailored to your signal. Cheers, David _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
