Enclosure not stated · 1 knob

Electro Harmonix Doctor Q

Based on the Electro-Harmonix Doctor Q· 2 other boards clone it

Schematic

Ref	Value	Normalized	Type	Notes
Resistors 6
×3	470k	470k		read from the schematic by eye
×5	47k	47k		read from the schematic by eye
×1	47	47		op amp supply resistor from +9V; read from the schematic by eye
×1	22k	22k		read from the schematic by eye
×1	2.2M	2.2M		read from the schematic by eye
×1	100	100		read from the schematic by eye
Capacitors 5
×1	.01uF	10n		read from the schematic by eye
×2	.005uF	5n		read from the schematic by eye
×1	.001uF	1n		read from the schematic by eye
×2	.05uF	50n		read from the schematic by eye
×2	10uF	10u		electrolytic; read from the schematic by eye
Diodes 1
×2	1N914	1N914		read from the schematic by eye
Transistors 1
×1	BC239C	BC239C		NPN; 2N3904 given as alternate; read from the schematic by eye
ICs 1
×1	ECG778	ECG778		dual op amp, both sections used; read from the schematic by eye
Potentiometers 1
Sensitivity	100k	100k	Potentiometer	read from the schematic by eye
Trimmers 1
Range	25k	25k		Range trim; read from the schematic by eye
Switches 1
Norm/Bass	DPDT	DPDT		Norm/Bass switch; read from the schematic by eye