Parts · Transistors

OC79

Ge PNP BJT TH.2 circuits use this part. Listed as: Germanium transistor, PNP.

Selector table · a row in a maker's catalog, not a full datasheet; the part is discontinued

Substitutes Ge PNP 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
OC79	50	13 V	300 mA	0.55 W	0.2 MHz

Used on other boards here

Part	hFE min	Vce	Ic	Pc	fT	Boards
AC128	45	16 V	1000 mA	1 W	1 MHz	35
GT402B	60	25 V	500 mA	0.6 W	1 MHz	2
AC151	30	24 V	200 mA	0.9 W	1 MHz	2
NTE158	90	32 V	1000 mA	1.6 W	1.5 MHz	1

Closest by the numbers

Part	hFE min	Vce	Ic	Pc	fT
OC81Z	50	40 V	200 mA	0.6 W	0.2 MHz
GTC609B	50	50 V	700 mA	0.5 W
NKT304	50	20 V	2500 mA	0.75 W	0.4 MHz
OC84	50	20 V	500 mA	0.6 W	0.5 MHz
NKT261	50	12 V	500 mA	0.3 W	0.5 MHz
NKT245	50	15 V	1000 mA	0.3 W	0.5 MHz
SFT146	60	20 V	500 mA	0.55 W	0.3 MHz
NKT240	50	20 V	1000 mA	0.3 W	0.5 MHz

Faceplate	Circuit	Based on	Category	Vendor	Box	Knobs	Price	BOM
	Castledine Electronics Magical Mystery Box Vero22×23 Verified BC549C · OC79 Castledine Magical Mystery Box	Castledine Magical Mystery Box	Fuzz	Dirtbox Layouts	—	4	—	40
	Mystery Machine BC549C · OC79 Castledine Magical Mystery Box · 1590BB	Castledine Magical Mystery Box	Fuzz	PedalPCB	1590BB	5	$15.00	60