i have pc400 v1.5 how can i update to v4.3 ?
PC400 v4.0, v4.1, v4.2 can be upgraded to v4.3 for free using the patch downloaded for free from campbellsci.com/support.
However v1.5 is old enough that you will need to purchase an upgrade - call your Campbell Scientific rep and
order "PC400 /U"
what's the difference between PC400 1.5 and 4.3
The changes can be seen by looking at the revision histories posted on the website at https://www.campbellsci.com/revisions?dl=86 .