August 1986

6

Philips Semiconductors

Product specification

VHF power transistor

BLV21

APPLICATION INFORMATION

List of components:

f (MHz)

η (%)

175

28

15

< 1,5

> 10

< 0,83

> 65

1,4

+ j1,85

33

− j27,5

C1

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

C2

= C6 = 5 to 60 pF film dielectric trimmer (cat. no. 2222 809 07011)

C3

= 27 pF ceramic capacitor (500 V)

C4

= 120 pF ceramic capacitor (500 V)

C5

= 100 nF polyester capacitor

L1

= 1 turn Cu wire (1,6 mm); int. dia. 8,4 mm; leads 2

× 5 mm

L2

= 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); tap for C3 at 5 mm from transistor

L6

= 3 turns closely wound enamelled Cu wire (1,0 mm); int. dia. 9,0 mm; leads 2

× 5 mm

L7

= 3 turns closely wound enamelled Cu wire (1,0 mm); int. dia. 8,2 mm; leads 2

× 5 mm

L4 and L5 are strips on a double Cu-clad printed-circuit board with epoxy fibre-glass dielectric,

thickness 1/16".

R1

= R2 = 10

Ω carbon resistor

Component layout and printed-circuit board for 175 MHz test circuit see Fig.8.

Fig.7 Test circuit; c.w. class-B.

handbook, full pagewidth

MGP253

50

Ω

50

Ω

C1

L1

L3

R1

L2

L6

L5

L7

L4

C2

C3

T.U.T.

C4

C5

+VCC

C6

C7