29
StationPro Main Circuit Board – Top View
(1) The main circuit board has provisions for a “default” amplifier keying circuit and an
“alternate” amplifier keying circuit, and the builder must choose which circuit to use. The
default circuit (rated at 400V @ 250 mA, AC or DC of either polarity) is recommended
for nearly all applications. The alternate circuit (rated at 3.5A, 200V, positive polarity
only), should only be used for keying very high current, positive voltage relays.
CHOOSE ONLY ONE CIRCUIT!
Now install the selected components, as illustrated
below:
Note the white dot on K114. Be sure to get the orientation right when you install this component.
Default Amp Keying Circuit: Install K114 and R106 (brown-black-red). Make
sure the notch on K114 is aligned with the notch on the silk-screened outline.
Note the white dot near pin 1. K114 looks like a 6-pin IC.
