This is a diagram of the daughtercard connecter pins (viewed from the component side of the wfd). The pin numbering is inelegant for historical reasons, but corresponds to the daughtercard circuit diagram. Pin # signal -------- -------------- Top J4-12 n.c. J4-11 VEE (-5.2 V) J4-10 _DISC3 \ J4-9 DISC3 | J4-8 _DISC2 | differential ECL J4-7 DISC2 | discriminator signals J4-6 _DISC1 | for each input (0-3) J4-5 DISC1 | J4-4 _DISC0 | J4-3 DISC0 / J4-2 GND J4-1 VCC (+5 V) J3-1 +6 V J3-2 n.c. J3-3 THR0 \ J3-4 GND | J3-5 THR1 | comparator threshold J3-6 GND | voltages J3-7 THR2 | J3-8 GND | J3-9 THR3 / J3-10 GND J3-11 AN_IN <--- analog output (input to FADC) Bottom J3-12 -6V