Wayne.B wrote:

For driving I use Street Atlas on a laptop with Delorme's little
postage stamp sized GPS on the dashboard. That GPS is fantastic for
its size and price. It usually acquires in less than 15 seconds and
gets its power from the USB port.

How does it manage less than 15 seconds it it's been turned off long
enough that the ephemeris is no longer current? The message with the
ephemeris data takes 18 seconds to transmit and repeats every 30 seconds.
Hard to see how any unit could get a lock in 15 seconds. Of course you
should start timing from when you first apply power since that probably
starts the acquisition process.