[time-nuts] Thunderbolt GPS Receivers

[David I. Emery]

On Sat, Jan 27, 2007 at 09:57:30PM -0600, Didier Juges wrote:
> There is also the HP 58540A that looks a lot like the Thunderbolt, but 
> the specs are not nearly as good. I have not seen any of those on eBay 
> in a while either.
> http://www.realhamradio.com/58540A.htm

	I'm curious as to whether anyone has actually MEASURED 58540A
performance and compared it with a Thunderbolt.   Clearly the standard
58540A has MUCH worse specified holdover performance, but unless that is
important to you the actual 1 PPS jitter statistics (ADEV) and accuracy
relative to UTC and the related 10 mhz stability in various taus would
be what would count for most of us as actual holdover operation happens
less often, at least for significant intervals.  And then of course
phase noise, close and far... counts for many applications too.

	The Thunderbolt has lots of tweaks and the 58540A few, but for
many uses this is not a big issue.   Just curious as to how good or bad
the relative performance is WHEN LOCKED.


-- 
   Dave Emery N1PRE,  die at dieconsulting.com  DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole - in 
celebration of what could have been, but wasn't and is not to be now either."