billd@fps.com (Bill Davidson) (05/04/91)
Thanks to all who answered my previous query about how to set up without a reference clock. I got a few different alternative ways to do the job and I'm still trying to decide which one I like best. I now have xntp. Anyway, one person mentioned that it is trivial to build a CHU clock with a shortwave and an old 300 baud acoustic modem. However, ignorant as I am when it comes to hardware and radio, I wouldn't know how to do this. Also, I don't know how much it would cost. I might consider getting a reference clock if I could get one cheaply. I'm pretty sure I could scare up an acoustic coupler somewhere. I'd have to buy a radio and antenna though. It seems to me that this would be good information to include with the source. refclock_chu.c briefly mentions a little bit but it's still not enough detail for me. I looked for a write-up on this on louie.udel.edu but I couldn't find one. The only clock I've found is the Heath GC-1000 Most Accurate Clock at $399. This is far more than I can come up with for this. The latest clock.txt off of louie.udel.edu (dated 3/31/91) says it's $350. The Spring 1991 Home Automation by Heath catalog says it's $399. I am curious as to why clock.txt says "It is supported (reluctantly) in the Fuzzball operating system." Why no UNIX capability? This is by far the cheapest one listed. What's wrong with it? The documentation for xntp only talks about the PST, Spectracom 8170 and CHU clocks. However, include/ntp.h shows HEATH, and two GOES clocks as well. The source seems to indicate that these are not supported by the software. Why? I'd like any information about how to set up a reference clock cheaply. Why are radio clocks with serial interfaces so expensive? --Bill Davidson (billd@fps.com)