Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : Trimble Navigation -- Ignore unavailable to you. Want to Upgrade?

To: zax who wrote (3438)	6/24/2012 11:23:29 PM
From: GPS Info	Read Replies (1) \| Respond to of 3506

Those are interesting results. TTFF results are a function of current ephemeris and then current almanacs. Usually, if the ephemeris data are less than two hours old (and the last position is stored) a receiver should get a TTFF in 10 seconds or less. I saw Trimble TTFF values at around 5 seconds for their GIS receiver – about 15 years ago. If the ephemeris data are older than two hours, the almanacs can be used to start tracking within a few seconds in open sky conditions. It takes at most 30 seconds to decode the current ephemeris data and so the 35 seconds was probably adding a 5-second cushion. If the ublox unit was getting 10 second TTFFs, then they must have been storing ephemeris data in flash. I couldn’t say why the Trimble didn’t.