Gordon, I would chime in praising these instruments, also having one of these beautifully constructed 3810 Total Stations. Brought it over from the US many years ago in my hand luggage =D, hoping to be able to fix it some day, but searching for a service manual ever since. Mine has no laser beam output, for whatever reason, but everything else works. This thingy does not seem to be very complicated, but way too complicated to be able to successfully poking around... Chris