[time-nuts] Bodnar "Precision Frequency Reference (GPS Clock)" AND LeoNTP Networked Time NTP Server Questions

Clay Autery cautery at montac.com
Thu May 17 22:19:53 EDT 2018


Anyone who is using one (or both) of these, and/or folks who have a 
logical opinion:

*"GPSDO"* - Once configured, unit can run on an external DC source 
(5-15VDC).  I am NOT using it to power the mast mounted timing antenna.  
I don't anticipate leaving unit connected to a computer when not 
configuring UNLESS I can figure out how to grab data from the unit via 
the USB port for reporting/analysis.

Questions:
1)  What are the specs of the DC plug on the back?  If I use an external 
supply, I want to eliminate the addition of yet another SMPS/wall wart 
to the clutter.

2) IF you were choosing a voltage to run JUST this unit on 
big/short/twisted/ferited leads, what voltage would you choose 
(regulating down from 13.8VDC or so).  Anything above the required 
minimum will be converted to heat in either the unit or at the 
regulator.  Considering this uses a TXCO (I think) and not an OXCO or 
DOXCO, is running it hotter to try and achieve a more consistent 
internal temp worth the tradeoff in potentially shortened life of the 
unit.  (Bottom Line: What voltage will make it run most 
accurately/consistently?)

*LeoNTP Networked Time NTP Server* -  Can be powered via USB or PoE 
according to website.  Detailed specs are seriously lacking.  Trying to 
wade through how to power it.  USB is obviously 5vdc or a bit less....  
But the PoE could be much higher with an internal regulator(s)

-  I haven't bought my new switch yet, so I can buy one with PoE 
capability or otherwise inject PoE on the Ethernet cable from the NTP 
Server to the Gbit switch.
-  All Ethernet cables in my network are CAT-7 STP (shielded twisted 
pair) or better.  (Yeah, yeah, I know, wired Ethernet can be noisy, but 
you do the best you can.  IF wired Ethernet becomes an issue, I can back 
up to the wireless network.)
-  Not sure how much I plan to have the unit connected via USB. Beyond 
curiosity data gathering for a while, I'm thinking at some point I want 
it to be disco'd and forgotten.  One less potential USB cable radiating 
or needing ferrites.

There's more...  but this is a good start.  Just want to try and get 
parts on the way.  Have to build a separate outboard regulator for the 
timing GPS antenna, too.

Thanks!

-- 
*Clay Autery
(318) 518-1389
MONTAC Enterprises*


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