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To: GPS Info who wrote (3439)	6/25/2012 12:02:41 AM
From: zax	1 Recommendation Read Replies (1) of 3449

There was no backup power and these units don't have flash. These were all cold start times. I said that the ublox clocked in under 30s, sometimes as low as 20. It has a 1 sec hot start time (20uA backup power) which I didn't test. When I said the Trimble took 3X as long, I meant it would take up to 60-90 seconds regularly... nowhere near its claimed TTFF of 35 sec. So thats ephemeris + acquisition. The HDOP readings got low fast enough. My take is that the Trimble basically requires a much better signal than the 12x12 25db antenna we'd connected would give under a clear sky and inside the case of our law enforcement instrument where it was being tested. So perhaps the Trimble could cut 35sec outside our instrument... or under a repeater in a lab... but in my real-world outdoor testing it didn't approach it. In an identical setup, the ublox blew it away.