Re: [time-nuts] Book review: "How We Got To Now."

2017-09-04 Thread Mike Naruta AA8K
He also did a six part documentary on PBS in 2014. Great thinking. On 09/04/2017 10:32 PM, Nick Sayer via time-nuts wrote: I happened to be at Powell's bookstore in Portland the day after the eclipse and came across this book and wound up buying it. It's attraction to me was the same that

[time-nuts] Book review: "How We Got To Now."

2017-09-04 Thread Nick Sayer via time-nuts
I happened to be at Powell's bookstore in Portland the day after the eclipse and came across this book and wound up buying it. It's attraction to me was the same that I felt growing up watching the documentaries hosted by James Burke - Connections and The Day The Universe Changed. Both Burke

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Wes
I'm dating myself again but when I was employed at Hughes Aircraft we had an HP salesman dedicated to servicing just us.  So most everything came direct from them or Wiltron.  I liked traveling to HP events with him.  Hughes had a miserly expense reporting process.  His was, "I count the money

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Bob kb8tq
Hi A lot depends on just which outfit you buy your attenuators from. There certainly *are* outfits out there that supply you just over 20 db RL when the spec is 20. They also don’t charge very much for their attenuators …. Bob > On Sep 4, 2017, at 4:53 PM, jimlux wrote:

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread jimlux
On 9/4/17 1:18 PM, Wes wrote: If these are COTS attenuators, their own return loss is unlikely to be 40 dB. In fact grabbing an old HP catalog off my bookshelf (I'm dating myself) I see a typical type N attenuator specified as 1.2 VSWR (~21 dB RL). I went on a quick "shopping" trip looking

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Wes
Not being as nutty as many on this list I only skimmed the papers you provided.  Interesting and I will stand corrected regarding the use of 75 ohm cable in 50 ohm systems in critical situations.  In situations like my own, I'm not going to fuss about it. I realize this is NIST, the 1384

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Mark Spencer
Although not time nuts related I believe this document speaks to some of the practical issues... http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-6297.pdf Mark Spencer m...@alignedsolutions.com > On Sep 3, 2017, at 4:56 PM, Mark Sims wrote: > > Real time nuts run

[time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Mark Sims
Real time nuts run phase stable cable (some well over $50 / foot) in climate controlled ducts... which is all for nought unless you also climate control the antenna.Which is all standard practice for precision geodesy. Try to keep it all with a milli-Kelvin or two. Oh, and don't forget

Re: [time-nuts] GPS Antenna Feed Line Decision

2017-09-04 Thread Bob kb8tq
Hi If you are running into a TBolt, it’s got an F connector and 75 ohm cable spec’d already …. The 50 ohm / 75 ohm thing didn’t seem to bother Trimble. They certainly looked at it before going that way …. Bob > On Sep 4, 2017, at 12:31 AM, Ian Stirling wrote: > > On