August 1986

6

Philips Semiconductors

Product specification

HF/VHF power transistor

BLW86

APPLICATION INFORMATION

List of components:

L4 and L5 are strips on a double Cu-clad printed-circuit board with epoxy fibre-glass dielectric, thickness 1/6".

R1 = R2 = 10

Ω carbon resistor

Component layout and printed-circuit board for 175 MHz test circuit see Fig.9.

f (MHz)

η (%)

175

28

45

< 8

> 7,5

< 2,47

> 70

0,7

+ j1,3

110

− j62

C1 = C7 = 2,5 to 20 pF film dielectric trimmer (cat. no. 2222 809 07004)

C2 = 5 to 60 pF film dielectric trimmer (cat. no. 2222 809 07011)

C3a = C3b = 47 pF ceramic capacitor (500 V)

C4 = 120 pF ceramic capacitor

C5 = 100 nF polyester capacitor

C6a = 2,2 pF ceramic capacitor (500 V)

C6b = 1,8 pF ceramic capacitor (500 V)

C8 = 4 to 40 pF film dielectric trimmer (cat. no. 2222 809 07008)

L1 = 14 nH; 1 turn Cu wire (1,6 mm); int. dia. 7,7 mm; leads 2

× 5 mm

L2 = 100 nH; 7 turns closely wound enamelled Cu wire (0,5 mm); int. dia. 3 mm; leads 2

× 5 mm

L3 = L8 = Ferroxcube wide-band h.f. choke, grade 3B (cat. no. 4312 020 36640)

L4 = L5 = strip (12 mm

× 6 mm); taps for C3a and C3b at 5 mm from transistor

L6 = 80 nH; 3 turns Cu wire (1,6 mm); int. dia. 9,0 mm; length 8,0 mm; leads 2

× 5 mm

L7 = 62 nH; 3 turns Cu wire (1,6 mm); int. dia. 7,5 mm; length 8,1 mm; leads 2

× 5 mm

Fig.8 Test circuit; c.w. class-B.

handbook, full pagewidth

C7

50

Ω

50

Ω

MGP604

,,

,,

,,

C1

C2

C3b

C3a

C6a

C4

C5

R2

L3

C6b

C8

L1

L2

L4

R1

L5

L7

T.U.T.

L6

L8

+VCC