Parts · Transistors

BD139

Si NPN BJT TO-126 TH.3 circuits use this part.

Datasheet · from onsemi.com

Substitutes Si 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
BD139	40	80 V	1000 mA	12 W	50 MHz

Used on other boards here

Part	hFE min	Vce	Ic	Pc	fT	Boards
BD1396STU	40	80 V	1500 mA	12.5 W		1
BD13910STU	40	80 V	1500 mA	12.5 W		1
MPS-U05	60	60 V	2000 mA	10 W	170 MHz	1
2N5008	70	80 V	10000 mA	100 W	40 MHz	3
2SD880	60	60 V	3000 mA	30 W	3 MHz	1

Closest by the numbers

Part	hFE min	Vce	Ic	Pc	fT
2SC1860	40	100 V	2000 mA	12 W
2N1715S	40	100 V	750 mA	10 W
2N1717S	40	100 V	750 mA	10 W
2N6413	40	60 V	4000 mA	15 W	50 MHz
2N6416	40	80 V	3000 mA	15 W	40 MHz
2N4897	40	80 V	5000 mA	7 W	50 MHz
2SC698	40	60 V	3000 mA	10 W	45 MHz
2N4309	40	80 V	5000 mA	11 W	80 MHz

Circuit	Based on	Category	Vendor	Box	Knobs	Price	BOM
Countenance Alliance Si BD139 · PN2369A 1590B	—	Other	delyk PCBs	1590B	3	—	17
Carlin phaser 741 · BC547 · BC557 · BD139	—	Phaser	Experimentalists Anonymous	—	3	—	32
Reverb Driver and Receiver BD139 · BD140 · LF351 · TL071	—	Reverb	Experimentalists Anonymous	—	3	—	23