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Discussion of precise time and frequency measurement

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Re: Query about List and about 10 MHz Distro

JG
Joseph Gwinn
Sun, Aug 29, 2021 4:46 PM

On Sun, 29 Aug 2021 03:30:23 -0400, time-nuts-request@lists.febo.com
wrote:
Re: time-nuts Digest, Vol 208, Issue 23 (message 3)

Date: Sat, 28 Aug 2021 18:57:08 -0500
From: Dana Whitlow k8yumdoober@gmail.com
Subject: [time-nuts] Re: Query about List and about 10 MHz Distro
To: Discussion of precise time and frequency measurement
time-nuts@lists.febo.com

Bob, my own motivation  for going to fiber was entirely different.  I
simply wanted to
run 10 MHz all over the place from reference sources in disparate
locations in the
house, and I quickly discovered that cable leakage was embarrassingly
severe.  So
I shut down and began contemplating a fiber link.  But then reality set in
and I realized
that running fiber across the house had its own big problems, so I set the
project aside.

Dana

I've run a lot of 10 MHz distribution coaxial cable, in a tree with
links as long as 50 meters, and planned systems where the links were
a few hundred meters.  It's necessary to use double-shielded coax
with machined TNC (not BNC) connectors on cables and the (passive)
power dividers.  The cable shielding effectiveness must exceed 80 dB
per meter.  Be sure  to torque the connectors to the "inspection
torque" range specified by the connector manufacturer.  At 10 MHz,
cable losses are minimal.

.https://patents.google.com/patent/US9261587B1

Joe Gwinn

On Sun, 29 Aug 2021 03:30:23 -0400, time-nuts-request@lists.febo.com wrote: Re: time-nuts Digest, Vol 208, Issue 23 (message 3) > Date: Sat, 28 Aug 2021 18:57:08 -0500 > From: Dana Whitlow <k8yumdoober@gmail.com> > Subject: [time-nuts] Re: Query about List and about 10 MHz Distro > To: Discussion of precise time and frequency measurement > <time-nuts@lists.febo.com> > > Bob, my own motivation for going to fiber was entirely different. I > simply wanted to > run 10 MHz all over the place from reference sources in disparate > locations in the > house, and I quickly discovered that cable leakage was embarrassingly > severe. So > I shut down and began contemplating a fiber link. But then reality set in > and I realized > that running fiber across the house had its own big problems, so I set the > project aside. > > Dana I've run a lot of 10 MHz distribution coaxial cable, in a tree with links as long as 50 meters, and planned systems where the links were a few hundred meters. It's necessary to use double-shielded coax with machined TNC (not BNC) connectors on cables and the (passive) power dividers. The cable shielding effectiveness must exceed 80 dB per meter. Be sure to torque the connectors to the "inspection torque" range specified by the connector manufacturer. At 10 MHz, cable losses are minimal. .<https://patents.google.com/patent/US9261587B1> Joe Gwinn