[time-nuts] Cesium C Field Set?

Brooke Clarke brooke at pacific.net
Fri Feb 11 12:18:43 EST 2005


Hi:

Yesterday I enabled the iono correction and it made an immediate 100 ns change, but the plot still has 100 ns moves.

I am also watching the Middletown 99400 LORAN-C station (less than 50 miles away) using a 2100T receiver.  The problem with it is that the minimum offset timing increment is 0.01 microseconds and there might be a few counts of noise on that.  So if I'm looking for parts in E-14 then it will take 3E6 seconds or 35 days.  

John: do you get more accuracy (or just more resolution) by using the external chart recorder output?

Anyone:  What time period is used in the Austron 2100x LORAN-C receiver for the frequency offset display?  I know the actual offset time interval is zeroed at start up or can be zeroed manually, but it's not clear to me how the offset value is calculated.

Anyone:  When making a time interval mesurement what effect does an error in the counter time base have on the result?

This morning it occurred to me that I still do not have the GPS properly setup.  I'm surrounded by high trees.  So I changed from all in view to best 4 and to highest in the sky and set the elevation mask to 30 degrees.  This should cut down on multipath problems.  I'm using the Motorola timing GPS antenna (the white upside down ice cream cone one) but do not have a choke ring under it. 

I either need to get the GPS receiver to have less wander or depend more on LORAN-C which so far has less wandering.

Have Fun,

Brooke
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