[time-nuts] Re: Query about List and about 10 MHz Distro

[David I. Emery]

On Sun, Aug 29, 2021 at 10:43:51AM -0400, paul swed wrote:

> Wellll my only issue is every time we had a lightning storm it seemed to
> fry the ICs.

	While they may not have ideal behavior with temperature (and
related phase/group delay changes) the old antique 10Mbs era balanced
twisted pair ethernet  transformer/filter modules did eliminate common
mode energy getting into the receivers (and transmitter) which it sounds
like was the cause of your lightning EMP problem.   For 10 MHz these
ought to work pretty well with twisted pairs as they provide galvanic
isolation breaking ground loops.   Not completely clear what the common
mode  Z of the things is at 10 MHz... but unless there is a deliberate
cap from a center tap to local ground I'd guess it would be
significantly high given just winding to winding capacitance.

	I do certainly beleive that optical transmission is the 
better solution... however.



-- 
  Dave Emery N1PRE/AE, die at dieconsulting.com  DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole - in 
celebration of what could have been, but wasn't and is not to be now either."