[time-nuts] New NTBW50AA

quartz55 quartz55 at hughes.net
Sat Sep 14 12:45:29 EDT 2013


Today I moved the antenna to above the beams.  This is temporary because it's in the way of the beams turning.  I guess I need to get someone out here to help me install it on top of the beam mast.  I don't feel confident to do it myself anymore.  I suppose it's not going to hurt anything if once in a while the antenna gets rotated?  Just not while I'm doing something with the Nortel.  It's pretty much in the clear and as high as I can get it.  It sees clear sky especially to the south except for one tree and the antenna is probably within 10' of that tree's height.  There are still trees to the east that I just can't do much about.  The ones to the west are about 100' away and the antenna shouldn't see them much.

http://i251.photobucket.com/albums/gg287/DogTi/time/abovebeams_zpsbf8474c1.jpg

So the Osc ppt is the offset from what the Nortel thinks is exactly 10MHz as I read it on page 117 of the ThunderBolt instructions (thanks Tom).  How do I tell how accurate the Nortel thinks exactly 10MHz is, or can I assume it's right?  If right is the case, then if I get a spread of around 300ppt, that means I'm always within 300x10^-9 Hz of 10MHz or .0003Hz at 1GHz?  Or is my thinking off base and did I miss a decimal somewhere?  I suppose the ppt spread is pretty much a function of how stable the osc is once other factors like temp, antenna position, sat acquisition, etc, are optimized?  That's what I infer from what Skip Withrow from RDR told me about the oscillators.  He told me they can vary by a factor of 10.

Dave
N3DT


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