Thanks Dana,
This helps a bit, but I am still puzzled over the + and - signs and what is the difference between the soldering iron icon at 10 o'clock and the one at 1:00 o'clock? Both look identical to me and both have the + sign.
I get that the 11 o'clock icon is probably the desoldering vacuum tool, but what the heck it the one at 2:00 o'clock?
Thanks to your pdf link, I now understand that the 12:00 o'clock position is for the hot air tool. I previously thought it was just for compressed air but now it all makes sense.
The only thing wrong with this station (so far) is the knob on the selector switch snapped off. According to Murphy's Law the shaft snapped off flush to the body of the switch. This is not a big deal right now because it snapped off in the "solder" position and since I don't have any of the optional tools, the solder position is the only one that I can use right now. The tools are so darned expensive that unless I can find used ones, I won't be using the on-board vacuum pump. Pity.
I can replace the switch but since I don't know the amps or voltages involved I might be wasting my money on a switch that melts during use. Hence the request for a service manual.