26
h. Now we’ll install the optocouplers on the main board. The leads need to be bent 90
degrees, but it matters which way you bend them for them to fit in the proper orientation.
If you put the opto in backwards your volume pedal will not work. Note the PCB graphics
indicate where the LDR and LED are intended to go. On your optocoupler, the LED has one
long lead and one short lead. The long lead of the LED goes into the hole with the square
pad. Note which side of the optocoupler needs to face up as you bend the leads down
in order for it to fit into the holes properly. Grip the leads with your pliers as shown (64)
and bend them down 90 degrees with your fingers. Bend the LDR’s leads in the same way,
holding with pliers and bending with fingers (65). Repeat for the other optocoupler.
64
65
i. Carefully install the optocoupler pair on the main PCB. The marked optocoupler goes in
OPTO1A. Make sure the long LED leads are in the holes with square pads (66,67).
66
67
j. Bend the leads out on the back, solder all 8 leads, and snip them flush (68).
68
