[time-nuts] FE-5680A Results so far

EWKehren at aol.com EWKehren at aol.com
Tue Dec 27 22:04:51 EST 2011

I just got back from running an other test on my 5680 and for 24 days now  
it has been reading consistently 9.99999999944 MHz! I average over 1000 
seconds  because feeding two Tbolts into a Tracor 527E I do see up to +_2 E-11 
changes  off and on, and one runs all my instruments. I am waiting for aging 
changes  before I modify the C field circuit. 
Bert Kehren
In a message dated 12/27/2011 11:52:27 A.M. Eastern Standard Time,  
caf at omen.com writes:

After a  few days of fooling around it appears my $38.00 Rb frequency  
is meeting its specs except for the current draw on the 5 volt  supply.

The attached plot shows phase readings between the Rb and a  ThunderBolt 
by a Racal-Dana 1992 counter read out by Fedora Linux 16  and a National 
PCI GPIB interface.  I entered various  frequency offsets with my own 
comms software
downloadable from  omen.com.

The "transients" are manual slewing events where I set an  offset of 0 
until the phase
swings around to 180 degrees.  The  last such event covered 360 degrees 
in about 100
seconds; the result  agrees with the specified resolution of 1e-12.

The Rb seems to be  meeting its 10-11/day spec.  If I did the math 
correctly,  that
corresponds to measuring the distance to the Moon within tenths of an  inch.

My next step is to leave it alone for a day or two.

Chuck Forsberg WA7KGX N2469R     caf at omen.com    www.omen.com
Developer of Industrial ZMODEM(Tm) for Embedded  Applications
Omen Technology Inc      "The High  Reliability Software"
10255 NW Old Cornelius Pass Portland OR  97231    503-614-0430

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