[time-nuts] New NTBW50AA

quartz55 quartz55 at hughes.net
Mon Sep 9 09:14:59 EDT 2013


Wait a minute, Bob.  I have an LPRO with good reported bulb voltatge.  Are you telling me this TBolt is no better than the Rb standard, as far as stability and perhaps worse?  And the frequency accuracy is also no better and both have to be compared to a Cs or H Maser to be calibtated?  I thought the GPS put out these precise second pulses that the TBolt would measure over time and discipline the OCXO to those precision seconds over time resulting in a variable (very small) but precise  statistical frequency (unlike the Rb which is just very stable) and thus having a reference back to NIST to a degree. (in my simplistic language)

Yes, I'm not fully understanding the Tau and ADEV I'm sure.  I did read it's the sq root of Allan variance.  So the reported 10000 Tau ADEV is not a measurement of the variance of the frequency compared to the precise 1 second marks over time?  I thought if I had 1.0e-12 that was comparable to knowing it's within 1Hz at a billion (10^12) Hz?

Should I reverse the &a command I did and let it run in the mode I got it in?  The 10000 ADEV is back down to 1.6e-12 this morning.  You can see the screenshot here, http://s251.photobucket.com/user/DogTi/media/time/20139-91229_zps7e475453.jpg.html it looks like the temp is still jumping but for some reason the number of sats has increased, a lot,  maybe it's just the harmonic convergence.

Is that white line that runs around the center essentially the frequency variance?  And why do I have what appears to be multiple blue and red lines?

So many questions, so little time.  Anyhow, as soon as it warms up a bit and I have my Earl Grey, I'm going to turn this thing off and go reset the antenna and see what happens, I need to make a bracket which won't take long.  I just worry about climbing up the ladder these days since I had a herniated disc removed and a spacer installed this spring.  At least the pain is gone and I'm not in a wheelchair.

Dave
N3DT


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