Parts · Transistors

MP37B

1 circuit uses this part.

Substitutes Ge NPN transistor

Matched on material, polarity and the limits below from the transistor parameter database. Pinouts and packages are not in that data: check the datasheet before you drop one in, and expect gain to change the sound.

This part

Part	hFE min	Vce	Ic	Pc	fT
MP37B	25	30 V	20 mA	0.15 W	1 MHz

Used on other boards here

Part	hFE min	Vce	Ic	Pc	fT	Boards
MP10B	25	30 V	20 mA	0.15 W	1 MHz	1
2N1302	20	25 V	300 mA	0.15 W	1 MHz	2
GT404B	60	25 V	500 mA	0.6 W	1 MHz	1

Closest by the numbers

Part	hFE min	Vce	Ic	Pc	fT
AC127Z	25	40 V	500 mA	0.175 W	1 MHz
AC340	30	24 V	50 mA	0.125 W	1 MHz
2N587	20	30 V	200 mA	0.2 W
AC330	20	24 V	50 mA	0.125 W	1 MHz
2N385	30	25 V	200 mA	0.15 W	2 MHz
NKT732	20	25 V	300 mA	0.15 W	2 MHz
2N438	20	25 V	300 mA	0.1 W	1.5 MHz
2SC128	30	25 V	200 mA	0.15 W	3 MHz

Faceplate	Circuit	Based on	Category	Vendor	Box	Knobs	Price	BOM
	Annihilator Fuzz MP37B	Dream Crusher	Fuzz	Fuzz Dog	1590B	3	£33.60	19