August 1986

8

Philips Semiconductors

Product specification

HF/VHF power transistor

BLW50F

R.F. performance in s.s.b. class-AB operation (linear power amplifier)

List of components:

Note

1. Stated intermodulation distortion figures are referred to the according level of either of the equal amplified tones.

Relative to the according peak envelope powers these figures should be increased by 6 dB.

OUTPUT POWER

W

dB

AT 65 W P.E.P.

dB

dB

mA

°C

10 to 65 (P.E.P.)

typ. 18

typ. 45

typ. 1,45

typ.

−30

<−30

50

25

C1

=

C2 = 10 to 780 pF film dielectric trimmer

C3

=

C5 = C6 = 220 nF polyester capacitor

C4

=

120 pF ceramic capacitor (500 V)

C7

=

150 pF ceramic capacitor (500 V)

C8

=

47

µF/63 V electrolytic capacitor

C9

=

3,9 nF ceramic capacitor

L1

=

4 turns closely wound enamelled Cu wire (1,6 mm); int. dia 7,0 mm; leads 2

× 5 mm

L2

=

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

L3

=

9 turns enamelled Cu wire (1,0 mm); int. dia. 10 mm; length 14,5 mm; leads 2

× 5 mm

L4

=

6 turns enamelled Cu wire (1,0 mm); int. dia. 6,5 mm; length 11,0 mm; leads 2

× 5 mm

R1

=

2,4

Ω; parallel connection of 2 × 4,7 Ω carbon resistors

R2

=

39

Ω carbon resistor

Fig.10 Test circuit; s.s.b. class-AB.

handbook, full pagewidth

MGP474

50

Ω

50

Ω

C2

L2

L3

C7

R2

C1

+VCC

L1

R1

T.U.T.

C9

L4

C4

C5

C6

C8

C3

temperature

compensated bias

(Ri < 0.1 Ω)