Hmm, I don't see anything referencing 15v or 18v versions. Where are you seeing that?
As far as I can tell there are two versions of the SPS switching boards.
1) Truesoft SPS - this is mostly thru hole components with 2-3 smd ics on the back.
2) SPS System - this has mostly smd components and was designed for mass production. I think he only sold these fully assembled
You want the Truesoft SPS pdf in the assembly folder
As far as I can tell there are two versions of the SPS switching boards.
1) Truesoft SPS - this is mostly thru hole components with 2-3 smd ics on the back.
2) SPS System - this has mostly smd components and was designed for mass production. I think he only sold these fully assembled
You want the Truesoft SPS pdf in the assembly folder