Here we have a
AGA GeoDimeter 12A Medium Range Distance IR Measuring Surveying Instrument
I am no professional Survey person and purchased this to plot out the couple of pieces of land I have.
This is very easy to use. I have shown it powered up and measuring the distance between me and a mirror in the house.
You will need a tripod, and some mirrors. They sell them on here and they are about 100 bucks for 7 or 8 of them.
It requires an external 6V power supply. ( I used a Motorbike battery as it lasted a long time but they do smaller 6V batteries you could use. )
The power cord is supplied.
Basically all you do is pop it on a tripod ( you could convert a camera tripod) Aim it at the stick with a mirror on top using thecoarseSighting on the instrument. Power it up, press start. This then sends an IR signal out which reflects off the mirror. Watch the little meter and adjustuntilit receives a signal. You will hear an audible tone and the distance will be displayed in feet on the LED readout. Basically that is it.
So you will need reflectors. On sticks are good. You will require a 6VDC power supply.
Now I found it great, but I am no pro at it. Better than spending Nearly a 1000 bucks for someone else to do the same thing. I cannot let you know how accurate it is , but when I measured it out using a Wheel it was very close. Now that could be me waggling the measuring wheel and not walking in a straight line.
Please see pictures for cosmetic condition

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